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Charles, Hal Cecil

Overview:



Dr. Charles is an Associate Professor of Radiology, a chemist and an expert in MR imaging and spectroscopy with over 25 years of experience in nuclear magnetic resonance. He serves as the Co-Director of the Duke Center for Advanced Magnetic Resonance Development. He also has extensive experience in conducting imaging and spectroscopy studies. He has had extensive experience in conducting longitudinal clinical trials with MRI and MRS used as imaging biomarkers. He is also director of the Duke Image Analysis Laboratory which is active in conducting clinical trials in CNS disorders (schizophrenia, MCI, AD), cancer, osteoarthritis and lung disease using imaging based biomarkers. His lab recently initiated a new project in imaging lung ventilation in humans with 19F MRI.

Positions:

Associate Professor of Radiology

Radiology
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

Ph.D. 1981

Ph.D. — University of New Orleans

Grants:

Human Lung Regional Ventilation Defect Severity Measured by Fluorine-19 Gas MRI

Administered By
Radiology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 15, 2012
End Date
April 30, 2018

PTSD & Childhood Sexual Abuse: Psychobiology

Administered By
Psychiatry, Child & Family Mental Health and Developmental Neuroscience
AwardedBy
National Institutes of Health
Role
Consultant
Start Date
September 09, 2002
End Date
August 31, 2009

PTSD & Childhood Sexual Abuse: Psychobiology

Administered By
Psychiatry, Child & Family Mental Health and Developmental Neuroscience
AwardedBy
National Institutes of Health
Role
Consultant
Start Date
September 09, 2002
End Date
August 31, 2008

Child Neglect: Psychobiological Consequences

Administered By
Psychiatry, Child & Family Mental Health and Developmental Neuroscience
AwardedBy
National Institutes of Health
Role
Consultant
Start Date
September 29, 2000
End Date
August 31, 2007

Adolescent Alcohol Abuse, PTSD & Hippocampal Development

Administered By
Psychiatry, Child & Family Mental Health and Developmental Neuroscience
AwardedBy
National Institutes of Health
Role
Co Investigator
Start Date
September 30, 2002
End Date
March 31, 2006

Predicting Human Tumor Response by 31p MRS

Administered By
Radiology, Neuroradiology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 21, 1995
End Date
February 28, 2001

Depression In Late Life

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
December 01, 1995
End Date
November 30, 1999

Hyperthermia And Perfusion Effects In Cancer Therapy

Administered By
Radiation Oncology
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
August 01, 1997
End Date
July 31, 1999

Hyperthermia And Perfusion Effects In Cancer Therapy

Administered By
Radiation Oncology
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
September 29, 1995
End Date
July 31, 1999

Hyperthermia And Perfusion Effects In Cancer Therapy

Administered By
Radiation Oncology
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
June 01, 1987
End Date
July 31, 1999

Alzheimers Disease -- Antemortem Markers

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
April 01, 1995
End Date
March 31, 1999

Predicting Human Tumor Response By 31p Mrs

Administered By
Radiology
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
July 21, 1995
End Date
February 28, 1999

Cortisol Cognition Brain Atrophy And Depression

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
September 01, 1996
End Date
August 31, 1998

Alzheimer'S Disease: Antemortem Markers

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
April 01, 1995
End Date
March 31, 1998

Alzheimers Disease-- Antemortem Markers

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
April 01, 1995
End Date
March 31, 1998

Cortisol Cognition Brain Atrophy And Depression

Administered By
Psychiatry & Behavioral Sciences
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
September 01, 1989
End Date
August 30, 1997

Hyperthermia And Perfusion Effects In Cancer Therapy

Administered By
Radiation Oncology
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
June 01, 1993
End Date
May 31, 1995

Specific Applications Of Pet And Mrs In Brain Tumors

Administered By
Radiology, Nuclear Medicine
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
April 01, 1994
End Date
March 31, 1995

Scor In Coronary And Vascular Diseases

Administered By
Medicine, Cardiology
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
January 01, 1992
End Date
December 31, 1994
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Publications:

Diseased Region Detection of Longitudinal Knee Magnetic Resonance Imaging Data.

Magnetic resonance imaging (MRI) has become an important imaging technique for quantifying the spatial location and magnitude/direction of longitudinal cartilage morphology changes in patients with osteoarthritis (OA). Although several analytical methods, such as subregion-based analysis, have been developed to refine and improve quantitative cartilage analyses, they can be suboptimal due to two major issues: the lack of spatial correspondence across subjects and time and the spatial heterogeneity of cartilage progression across subjects. The aim of this paper is to present a statistical method for longitudinal cartilage quantification in OA patients, while addressing these two issues. The 3D knee image data is preprocessed to establish spatial correspondence across subjects and/or time. Then, a Gaussian hidden Markov model (GHMM) is proposed to deal with the spatial heterogeneity of cartilage progression across both time and OA subjects. To estimate unknown parameters in GHMM, we employ a pseudo-likelihood function and optimize it by using an expectation-maximization (EM) algorithm. The proposed model can effectively detect diseased regions in each OA subject and present a localized analysis of longitudinal cartilage thickness within each latent subpopulation. Our GHMM integrates the strengths of two standard statistical methods including the local subregion-based analysis and the ordered value approach. We use simulation studies and the Pfizer longitudinal knee MRI dataset to evaluate the finite sample performance of GHMM in the quantification of longitudinal cartilage morphology changes. Our results indicate that GHMM significantly outperforms several standard analytical methods.

Authors
Huang, C; Shan, L; Charles, HC; Wirth, W; Niethammer, M; Zhu, H
MLA Citation
Huang, C, Shan, L, Charles, HC, Wirth, W, Niethammer, M, and Zhu, H. "Diseased Region Detection of Longitudinal Knee Magnetic Resonance Imaging Data." IEEE transactions on medical imaging 34.9 (September 2015): 1914-1927.
PMID
25823031
Source
epmc
Published In
IEEE Transactions on Medical Imaging
Volume
34
Issue
9
Publish Date
2015
Start Page
1914
End Page
1927
DOI
10.1109/tmi.2015.2415675

Automatic atlas-based three-label cartilage segmentation from MR knee images.

Osteoarthritis (OA) is the most common form of joint disease and often characterized by cartilage changes. Accurate quantitative methods are needed to rapidly screen large image databases to assess changes in cartilage morphology. We therefore propose a new automatic atlas-based cartilage segmentation method for future automatic OA studies. Atlas-based segmentation methods have been demonstrated to be robust and accurate in brain imaging and therefore also hold high promise to allow for reliable and high-quality segmentations of cartilage. Nevertheless, atlas-based methods have not been well explored for cartilage segmentation. A particular challenge is the thinness of cartilage, its relatively small volume in comparison to surrounding tissue and the difficulty to locate cartilage interfaces - for example the interface between femoral and tibial cartilage. This paper focuses on the segmentation of femoral and tibial cartilage, proposing a multi-atlas segmentation strategy with non-local patch-based label fusion which can robustly identify candidate regions of cartilage. This method is combined with a novel three-label segmentation method which guarantees the spatial separation of femoral and tibial cartilage, and ensures spatial regularity while preserving the thin cartilage shape through anisotropic regularization. Our segmentation energy is convex and therefore guarantees globally optimal solutions. We perform an extensive validation of the proposed method on 706 images of the Pfizer Longitudinal Study. Our validation includes comparisons of different atlas segmentation strategies, different local classifiers, and different types of regularizers. To compare to other cartilage segmentation approaches we validate based on the 50 images of the SKI10 dataset.

Authors
Shan, L; Zach, C; Charles, C; Niethammer, M
MLA Citation
Shan, L, Zach, C, Charles, C, and Niethammer, M. "Automatic atlas-based three-label cartilage segmentation from MR knee images." Medical image analysis 18.7 (October 2014): 1233-1246.
PMID
25128683
Source
epmc
Published In
Medical Image Analysis
Volume
18
Issue
7
Publish Date
2014
Start Page
1233
End Page
1246
DOI
10.1016/j.media.2014.05.008

Physiorack: An integrated MRI safe/conditional, Gas delivery, respiratory gating, and subject monitoring solution for structural and functional assessments of pulmonary function

Purpose To evaluate the use of a modular MRI conditional respiratory monitoring and gating solution, designed to facilitate proper monitoring of subjects' vital signals and their respiratory efforts, during free-breathing and breathheld 19 F, oxygen-enhanced, and Fourier-decomposition MRI-based acquisitions. Materials and Methods All Imaging was performed on a Siemens TIM Trio 3 Tesla MRI scanner, following Institutional Review Board approval. Gas delivery is accomplished through the use of an MR compatible pneumotachometer, in conjunction with two three-way pneumatically controlled Hans Rudolph Valves. The pneumatic valves are connected to Douglas bags used as the gas source. A mouthpiece (+nose clip) or an oro-nasal Hans Rudolph disposable mask is connected following the pneumatic valve to minimize dead-space and provide an airtight seal. Continuous monitoring/sampling of inspiratory and expiratory oxygen and carbon dioxide levels at the mouthpiece/mask is achieved through the use of an Oxigraf gas analyzer. Results Forty-four imaging sessions were successfully monitored, during Fourier-decomposition (n = 3), fluorine-enhanced (n = 29), oxygen-enhanced, and ultra short echo (n = 12) acquisitions. The collected waveforms, facilitated proper monitoring and coaching of the subjects. Conclusion We demonstrate an inexpensive, off-the-shelf solution for monitoring these signals, facilitating assessments of lung function. Monitoring of respiratory efforts and exhaled gas concentrations assists in understanding the heterogeneity of lung function visualized by gas imaging. J. Magn. Reson. Imaging 2014;39:735-741. © 2013 Wiley Periodicals, Inc. Copyright © 2013 Wiley Periodicals, Inc.

Authors
Halaweish, AF; Charles, HC
MLA Citation
Halaweish, AF, and Charles, HC. "Physiorack: An integrated MRI safe/conditional, Gas delivery, respiratory gating, and subject monitoring solution for structural and functional assessments of pulmonary function." Journal of Magnetic Resonance Imaging 39.3 (March 1, 2014): 735-741.
Source
scopus
Published In
Journal of Magnetic Resonance Imaging
Volume
39
Issue
3
Publish Date
2014
Start Page
735
End Page
741
DOI
10.1002/jmri.24219

Physiorack: an integrated MRI safe/conditional, gas delivery, respiratory gating, and subject monitoring solution for structural and functional assessments of pulmonary function.

PURPOSE: To evaluate the use of a modular MRI conditional respiratory monitoring and gating solution, designed to facilitate proper monitoring of subjects' vital signals and their respiratory efforts, during free-breathing and breathheld 19F, oxygen-enhanced, and Fourier-decomposition MRI-based acquisitions. MATERIALS AND METHODS: All Imaging was performed on a Siemens TIM Trio 3 Tesla MRI scanner, following Institutional Review Board approval. Gas delivery is accomplished through the use of an MR compatible pneumotachometer, in conjunction with two three-way pneumatically controlled Hans Rudolph Valves. The pneumatic valves are connected to Douglas bags used as the gas source. A mouthpiece (+nose clip) or an oro-nasal Hans Rudolph disposable mask is connected following the pneumatic valve to minimize dead-space and provide an airtight seal. Continuous monitoring/sampling of inspiratory and expiratory oxygen and carbon dioxide levels at the mouthpiece/mask is achieved through the use of an Oxigraf gas analyzer. RESULTS: Forty-four imaging sessions were successfully monitored, during Fourier-decomposition (n=3), fluorine-enhanced (n=29), oxygen-enhanced, and ultra short echo (n=12) acquisitions. The collected waveforms, facilitated proper monitoring and coaching of the subjects. CONCLUSION: We demonstrate an inexpensive, off-the-shelf solution for monitoring these signals, facilitating assessments of lung function. Monitoring of respiratory efforts and exhaled gas concentrations assists in understanding the heterogeneity of lung function visualized by gas imaging.

Authors
Halaweish, AF; Charles, HC
MLA Citation
Halaweish, AF, and Charles, HC. "Physiorack: an integrated MRI safe/conditional, gas delivery, respiratory gating, and subject monitoring solution for structural and functional assessments of pulmonary function." J Magn Reson Imaging 39.3 (March 2014): 735-741.
PMID
24123760
Source
pubmed
Published In
Journal of Magnetic Resonance Imaging
Volume
39
Issue
3
Publish Date
2014
Start Page
735
End Page
741
DOI
10.1002/jmri.24219

Perfluoropropane gas as a magnetic resonance lung imaging contrast agent in humans.

BACKGROUND: Fluorine-enhanced MRI is a relatively inexpensive and straightforward technique that facilitates regional assessments of pulmonary ventilation. In this report, we assess its suitability through the use of perfluoropropane (PFP) in a cohort of human subjects with normal lungs and subjects with lung disease. METHODS: Twenty-eight subjects between the ages of 18 and 71 years were recruited for imaging and were classified based on spirometry findings and medical history. Imaging was carried out on a Siemens TIM Trio 3T MRI scanner using two-dimensional, gradient echo, fast low-angle shot and three-dimensional gradient echo, volumetric, interpolated, breath-hold examination sequences for proton localizers and PFP functional scans, respectively. Respiratory waveforms and physiologic signals of interest were monitored throughout the imaging sessions. A region-growing algorithm was applied to the proton localizers to define the lung field of view for analysis of the PFP scans. RESULTS: All subjects tolerated the gas mixture well with no adverse side effects. Images of healthy lungs demonstrated a homogeneous distribution of the gas with sufficient signal-to-noise ratios, while lung images from asthmatic and emphysematous lungs demonstrated increased heterogeneity and ventilation defects. CONCLUSIONS: Fluorine-enhanced MRI using a normoxic PFP gas mixture is a well-tolerated, radiation-free technique for regionally assessing pulmonary ventilation. The inherent physical characteristics and applicability of the gaseous agent within a magnetic resonance setting facilitated a clear differentiation between normal and diseased lungs.

Authors
Halaweish, AF; Moon, RE; Foster, WM; Soher, BJ; McAdams, HP; MacFall, JR; Ainslie, MD; MacIntyre, NR; Charles, HC
MLA Citation
Halaweish, AF, Moon, RE, Foster, WM, Soher, BJ, McAdams, HP, MacFall, JR, Ainslie, MD, MacIntyre, NR, and Charles, HC. "Perfluoropropane gas as a magnetic resonance lung imaging contrast agent in humans." Chest 144.4 (October 2013): 1300-1310.
PMID
23722696
Source
pubmed
Published In
Chest
Volume
144
Issue
4
Publish Date
2013
Start Page
1300
End Page
1310
DOI
10.1378/chest.12-2597

Subchondral bone trabecular integrity predicts and changes concurrently with radiographic and magnetic resonance imaging-determined knee osteoarthritis progression.

OBJECTIVE: To evaluate subchondral bone trabecular integrity (BTI) on radiographs as a predictor of knee osteoarthritis (OA) progression. METHODS: Longitudinal (baseline, 12-month, and 24-month) knee radiographs were available for 60 female subjects with knee OA. OA progression was defined by 12- and 24-month changes in radiographic medial compartment minimal joint space width (JSW) and medial joint space area (JSA), and by medial tibial and femoral cartilage volume on magnetic resonance imaging. BTI of the medial tibial plateau was analyzed by fractal signature analysis using commercially available software. Receiver operating characteristic (ROC) curves for BTI were used to predict a 5% change in OA progression parameters. RESULTS: Individual terms (linear and quadratic) of baseline BTI of vertical trabeculae predicted knee OA progression based on 12- and 24-month changes in JSA (P < 0.01 for 24 months), 24-month change in tibial (P < 0.05), but not femoral, cartilage volume, and 24-month change in JSW (P = 0.05). ROC curves using both terms of baseline BTI predicted a 5% change in the following OA progression parameters over 24 months with high accuracy, as reflected by the area under the curve measures: JSW 81%, JSA 85%, tibial cartilage volume 75%, and femoral cartilage volume 85%. Change in BTI was also significantly associated (P < 0.05) with concurrent change in JSA over 12 and 24 months and with change in tibial cartilage volume over 24 months. CONCLUSION: BTI predicts structural OA progression as determined by radiographic and MRI outcomes. BTI may therefore be worthy of study as an outcome measure for OA studies and clinical trials.

Authors
Kraus, VB; Feng, S; Wang, S; White, S; Ainslie, M; Graverand, M-PHL; Brett, A; Eckstein, F; Hunter, DJ; Lane, NE; Taljanovic, MS; Schnitzer, T; Charles, HC
MLA Citation
Kraus, VB, Feng, S, Wang, S, White, S, Ainslie, M, Graverand, M-PHL, Brett, A, Eckstein, F, Hunter, DJ, Lane, NE, Taljanovic, MS, Schnitzer, T, and Charles, HC. "Subchondral bone trabecular integrity predicts and changes concurrently with radiographic and magnetic resonance imaging-determined knee osteoarthritis progression." Arthritis Rheum 65.7 (July 2013): 1812-1821.
PMID
23576116
Source
pubmed
Published In
Arthritis and Rheumatism
Volume
65
Issue
7
Publish Date
2013
Start Page
1812
End Page
1821
DOI
10.1002/art.37970

Diseased region detection of longitudinal knee MRI data.

Statistical analysis of longitudinal cartilage changes in osteoarthritis (OA) is of great importance and still a challenge in knee MRI data analysis. A major challenge is to establish a reliable correspondence across subjects within the same latent subpopulations. We develop a novel Gaussian hidden Markov model (GHMM) to establish spatial correspondence of cartilage thinning across both time and subjects within the same latent subpopulations and make statistical inference on the detection of diseased regions in each OA patient. A hidden Markov random field (HMRF) is proposed to extract such latent subpopulation structure. The EM algorithm and pseudo-likelihood method are both considered in making statistical inference. The proposed model can effectively detect diseased regions and present a localized analysis of longitudinal cartilage thickness within each latent subpopulation. Simulation studies and diseased region detection on 2D thickness maps extracted from full 3D longitudinal knee MRI Data for Pfizer Longitudinal Dataset are performed, which show that our proposed model outperforms standard voxel-based analysis.

Authors
Huang, C; Shan, L; Charles, C; Niethammer, M; Zhu, H
MLA Citation
Huang, C, Shan, L, Charles, C, Niethammer, M, and Zhu, H. "Diseased region detection of longitudinal knee MRI data." Information processing in medical imaging : proceedings of the .. conference 23 (2013): 632-643.
Source
scival
Published In
Information processing in medical imaging : proceedings of the ... conference
Volume
23
Publish Date
2013
Start Page
632
End Page
643

Diseased region detection of longitudinal knee MRI data

Statistical analysis of longitudinal cartilage changes in osteoarthritis (OA) is of great importance and still a challenge in knee MRI data analysis. A major challenge is to establish a reliable correspondence across subjects within the same latent subpopulations. We develop a novel Gaussian hidden Markov model (GHMM) to establish spatial correspondence of cartilage thinning across both time and subjects within the same latent subpopulations and make statistical inference on the detection of diseased regions in each OA patient. A hidden Markov random field (HMRF) is proposed to extract such latent subpopulation structure. The EM algorithm and pseudo-likelihood method are both considered in making statistical inference. The proposed model can effectively detect diseased regions and present a localized analysis of longitudinal cartilage thickness within each latent subpopulation. Simulation studies and diseased region detection on 2D thickness maps extracted from full 3D longitudinal knee MRI Data for Pfizer Longitudinal Dataset are performed, which show that our proposed model outperforms standard voxel-based analysis. © 2013 Springer-Verlag.

Authors
Huang, C; Shan, L; Charles, C; Niethammer, M; Zhu, H
MLA Citation
Huang, C, Shan, L, Charles, C, Niethammer, M, and Zhu, H. "Diseased region detection of longitudinal knee MRI data." Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 7917 LNCS (2013): 632-643.
PMID
24684005
Source
scival
Published In
Lecture notes in computer science
Volume
7917 LNCS
Publish Date
2013
Start Page
632
End Page
643
DOI
10.1007/978-3-642-38868-2_53

Longitudinal three-label segmentation of knee cartilage

Automatic accurate segmentation methods are needed to assess longitudinal cartilage changes in osteoarthritis (OA). We propose a novel general spatio-temporal three-label segmentation method to encourage segmentation consistency across time in longitudinal image data. The segmentation is formulated as a convex optimization problem which allows for the computation of globally optimal solutions. The longitudinal segmentation is applied within an automatic knee cartilage segmentation pipeline. Experimental results demonstrate that the longitudinal segmentation improves the segmentation consistency in comparison to the temporally-independent segmentation. © 2013 IEEE.

Authors
Shan, L; Charles, C; Niethammer, M
MLA Citation
Shan, L, Charles, C, and Niethammer, M. "Longitudinal three-label segmentation of knee cartilage." Proceedings - International Symposium on Biomedical Imaging (2013): 1376-1379.
Source
scival
Published In
Proceedings / IEEE International Symposium on Biomedical Imaging: from nano to macro. IEEE International Symposium on Biomedical Imaging
Publish Date
2013
Start Page
1376
End Page
1379
DOI
10.1109/ISBI.2013.6556789

Automatic multi-atlas-based cartilage segmentation from knee MR images

In this paper, we propose a multi-atlas-based method to automatically segment the femoral and tibial cartilage from T1 weighted magnetic resonance (MR) knee images. The segmentation result is a joint decision of the spatial priors from a multi-atlas registration and the local likelihoods within a Bayesian framework. The cartilage likelihoods are obtained from a probabilistic k nearest neighbor classification. Validation results on 18 knee MR images against the manual expert segmentations from a dataset acquired for osteoarthritis research show good performance for the segmentation of femoral and tibial cartilage (mean Dice similarity coefficient of 75.2% and 81.7% respectively). © 2012 IEEE.

Authors
Shan, L; Charles, C; Niethammer, M
MLA Citation
Shan, L, Charles, C, and Niethammer, M. "Automatic multi-atlas-based cartilage segmentation from knee MR images." Proceedings - International Symposium on Biomedical Imaging (2012): 1028-1031.
Source
scival
Published In
Proceedings / IEEE International Symposium on Biomedical Imaging: from nano to macro. IEEE International Symposium on Biomedical Imaging
Publish Date
2012
Start Page
1028
End Page
1031
DOI
10.1109/ISBI.2012.6235733

Automatic atlas-based three-label cartilage segmentation from MR knee images

This paper proposes a method to build a bone-cartilage atlas of the knee and to use it to automatically segment femoral and tibial cartilage from T1 weighted magnetic resonance (MR) images. Anisotropic spatial regularization is incorporated into a three-label segmentation framework to improve segmentation results for the thin cartilage layers. We jointly use the atlas information and the output of a probabilistic k nearest neighbor classifier within the segmentation method. The resulting cartilage segmentation method is fully automatic. Validation results on 18 knee MR images against manual expert segmentations from a dataset acquired for osteoarthritis research show good performance for the segmentation of femoral and tibial cartilage (mean Dice similarity coefficient of 78.2% and 82.6% respectively). © 2012 IEEE.

Authors
Shan, L; Charles, C; Niethammer, M
MLA Citation
Shan, L, Charles, C, and Niethammer, M. "Automatic atlas-based three-label cartilage segmentation from MR knee images." Proceedings of the Workshop on Mathematical Methods in Biomedical Image Analysis (2012): 241-246.
Source
scival
Published In
Proceedings of the Workshop on Mathematical Methods in Biomedical Image Analysis
Publish Date
2012
Start Page
241
End Page
246
DOI
10.1109/MMBIA.2012.6164757

Clinical, radiographic, molecular and MRI-based predictors of cartilage loss in knee osteoarthritis.

OBJECTIVE: To examine the relationship of baseline clinical, radiographic, molecular and MRI measures with structural progression (subregional MRI-based femorotibial cartilage loss) in knee osteoarthritis (OA). METHODS: Single knees of 75 female participants with radiographic knee OA (and 77 healthy control participants) were examined over 24 months using MRI. Subregional femorotibial cartilage thickness was determined at baseline and follow-up. Baseline clinical, radiographic, molecular (n=16) and quantitative MRI-based measures of the meniscus and cartilage, including delayed gadolinium-enhanced MRI (dGEMRIC) and T2, were obtained. Differences in these baseline measures between radiographic osteoarthritic knees with longitudinal cartilage thinning (or thickening) and those with no significant change were evaluated by receiver operator characteristic analyses and Wilcoxon rank sum tests. RESULTS: The relatively strongest predictors of longitudinal cartilage thinning were reduced baseline cartilage thickness in the medial femur (area under the curve (AUC)=0.81), varus malalignment (AUC=0.77), reduced minimum joint space width and a greater radiographic joint space narrowing (JSN) score (both AUC=0.74). These remained significant after adjusting for multiple comparisons using false discovery rates. Reduced bone resorption (C-terminal telopeptide of type I collagen; AUC=0.65) and a low dGEMRIC index (reflecting low proteoglycan content) in the medial tibia (AUC=0.68) were associated with longitudinal cartilage thinning, but failed to reach statistical significance after correction for multiple testing in this (small) sample. CONCLUSIONS: This exploratory study indicates that baseline molecular or MRI cartilage compositional markers may not provide better discrimination between knees with cartilage thinning and those without longitudinal change than simple radiographic measures, such as greater JSN score.

Authors
Eckstein, F; Le Graverand, MPH; Charles, HC; Hunter, DJ; Kraus, VB; Sunyer, T; Nemirovskyi, O; Wyman, BT; Buck, R; A9001140, investigators,
MLA Citation
Eckstein, F, Le Graverand, MPH, Charles, HC, Hunter, DJ, Kraus, VB, Sunyer, T, Nemirovskyi, O, Wyman, BT, Buck, R, A9001140, and investigators, . "Clinical, radiographic, molecular and MRI-based predictors of cartilage loss in knee osteoarthritis." Ann Rheum Dis 70.7 (July 2011): 1223-1230.
PMID
21622772
Source
pubmed
Published In
Annals of the rheumatic diseases
Volume
70
Issue
7
Publish Date
2011
Start Page
1223
End Page
1230
DOI
10.1136/ard.2010.141382

Age-associated increases in the size of the infrapatellar fat pad in knee osteoarthritis as measured by 3T MRI.

Obesity, as a primary risk factor for osteoarthritis (OA), has been shown to alter joint loading, but may also result in metabolic changes characterized by chronic, low-level inflammation due to increased circulating levels of adipose-derived cytokines, or "adipokines." The presence of the infrapatellar fat pad in the knee suggests that local changes in adipokine concentrations may influence knee OA. This study examined the hypotheses that the volume of the infrapatellar fat pad is correlated to the body mass index (BMI) of OA patients, and that fat pad volume is greater in subjects with OA. Fat pad volume was measured in sequential magnetic resonance (MR) images taken over one year in a cohort of 15 control and 15 knee OA subjects. No differences were observed in the fat pad volume between the two groups at baseline, 3, 6, or 12 months. In control subjects, no significant correlations were present between any parameters (age, BMI, weight, volume of fat pad at any time point). However, in the osteoarthritic group, fat pad volume was correlated with age at every time point. One possible explanation is that local factors related to knee OA may also induce enlargement of the fat pad with age. Alternatively, subjects who are prone to growth or enlargement of the fat pad may also be more prone to symptomatic OA. These findings provide intriguing preliminary data on the potential role of the infrapatellar fat pad in OA, although additional study is required to better understand the mechanisms of this relationship.

Authors
Chuckpaiwong, B; Charles, HC; Kraus, VB; Guilak, F; Nunley, JA
MLA Citation
Chuckpaiwong, B, Charles, HC, Kraus, VB, Guilak, F, and Nunley, JA. "Age-associated increases in the size of the infrapatellar fat pad in knee osteoarthritis as measured by 3T MRI." J Orthop Res 28.9 (September 2010): 1149-1154.
PMID
20225314
Source
pubmed
Published In
Journal of Orthopaedic Research
Volume
28
Issue
9
Publish Date
2010
Start Page
1149
End Page
1154
DOI
10.1002/jor.21125

A comparison of five approaches to measurement of anatomic knee alignment from radiographs.

OBJECTIVE: The recent recognition of the correlation of the hip-knee-ankle angle (HKA) with femur-tibia angle (FTA) on a standard knee radiograph has led to the increasing inclusion of FTA assessments in OA studies due to its clinical relevance, cost effectiveness and minimal radiation exposure. Our goal was to investigate the performance metrics of currently used methods of FTA measurement to determine whether a specific protocol could be recommended based on these results. METHODS: Inter- and intra-rater reliability of FTA measurements were determined by intraclass correlation coefficient (ICC) of two independent analysts. Minimal detectable differences were determined and the correlation of FTA and HKA was analyzed by linear regression. Differences among methods of measuring HKA were assessed by ANOVA. RESULTS: All five methods of FTA measurement demonstrated high precision by inter- and intra-rater reproducibility (ICCs>or=0.93). All five methods displayed good accuracy, but after correction for the offset of FTA from HKA, the femoral notch landmark method was the least accurate. However, the methods differed according to their minimal detectable differences; the FTA methods utilizing the center of the base of the tibial spines or the center of the tibial plateau as knee center landmarks yielded the smallest minimal detectable differences (1.25 degrees and 1.72 degrees, respectively). CONCLUSION: All methods of FTA were highly reproducible, but varied in their accuracy and sensitivity to detect meaningful differences. Based on these parameters we recommend standardizing measurement angles with vertices at the base of the tibial spines or the center of the tibia and comparing single-point and two-point methods in larger studies.

Authors
McDaniel, G; Mitchell, KL; Charles, C; Kraus, VB
MLA Citation
McDaniel, G, Mitchell, KL, Charles, C, and Kraus, VB. "A comparison of five approaches to measurement of anatomic knee alignment from radiographs." Osteoarthritis Cartilage 18.2 (February 2010): 273-277.
PMID
19897069
Source
pubmed
Published In
Osteoarthritis and Cartilage
Volume
18
Issue
2
Publish Date
2010
Start Page
273
End Page
277
DOI
10.1016/j.joca.2009.10.005

Change in regional cartilage morphology and joint space width in osteoarthritis participants versus healthy controls: a multicentre study using 3.0 Tesla MRI and Lyon-Schuss radiography.

OBJECTIVE: Cartilage morphology displays sensitivity to change in osteoarthritis (OA) with quantitative MRI (qMRI). However, (sub)regional cartilage thickness change at 3.0 Tesla (T) has not been directly compared with radiographic progression of joint space narrowing in OA participants and non-arthritic controls. METHODS: A total of 145 women were imaged at 7 clinical centres: 86 were non-obese and asymptomatic without radiographic OA and 55 were obese with symptomatic and radiographic OA (27 Kellgren-Lawrence grade (KLG)2 and 28 KLG3). Lyon-Schuss (LS) and fixed flexion (FF) radiographs were obtained at baseline, 12 and 24 months, and coronal spoiled gradient echo MRI sequences at 3.0 T at baseline, 6, 12 and 24 months. (Sub)regional, femorotibial cartilage thickness and minimum joint space width (mJSW) in the medial femorotibial compartment were measured and the standardised response means (SRMs) determined. RESULTS: At 6 months, qMRI demonstrated a -3.7% "annualised" change in cartilage thickness (SRM -0.33) in the central medial femorotibial compartment (cMFTC) of KLG3 subjects, but no change in KLG2 subjects. The SRM for mJSW in 12-month LS/FF radiographs of KLG3 participants was -0.68/-0.13 and at 24 months was -0.62/-0.20. The SRM for cMFTC changes measured with qMRI was -0.32 (12 months; -2.0%) and -0.48 (24 months; -2.2%), respectively. CONCLUSIONS: qMRI and LS radiography detected significant change in KLG3 participants at high risk of progression, but not in KLG2 participants, and only small changes in controls. At 12 and 24 months, LS displayed greater, and FF less, sensitivity to change in KLG3 participants than qMRI.

Authors
Le Graverand, M-PH; Buck, RJ; Wyman, BT; Vignon, E; Mazzuca, SA; Brandt, KD; Piperno, M; Charles, HC; Hudelmaier, M; Hunter, DJ; Jackson, C; Kraus, VB; Link, TM; Majumdar, S; Prasad, PV; Schnitzer, TJ; Vaz, A; Wirth, W; Eckstein, F
MLA Citation
Le Graverand, M-PH, Buck, RJ, Wyman, BT, Vignon, E, Mazzuca, SA, Brandt, KD, Piperno, M, Charles, HC, Hudelmaier, M, Hunter, DJ, Jackson, C, Kraus, VB, Link, TM, Majumdar, S, Prasad, PV, Schnitzer, TJ, Vaz, A, Wirth, W, and Eckstein, F. "Change in regional cartilage morphology and joint space width in osteoarthritis participants versus healthy controls: a multicentre study using 3.0 Tesla MRI and Lyon-Schuss radiography." Ann Rheum Dis 69.1 (January 2010): 155-162.
PMID
19103634
Source
pubmed
Published In
Annals of the rheumatic diseases
Volume
69
Issue
1
Publish Date
2010
Start Page
155
End Page
162
DOI
10.1136/ard.2008.099762

Utility of functional imaging in prediction or assessment of treatment response and prognosis following thermotherapy.

The purpose of this review is to examine the roles that functional imaging may play in prediction of treatment response and determination of overall prognosis in patients who are enrolled in thermotherapy trials, either in combination with radiotherapy, chemotherapy or both. Most of the historical work that has been done in this field has focused on magnetic resonance imaging/magnetic resonance spectroscopy (MRI/MRS) methods, so the emphasis will be there, although some discussion of the role that positron emission tomography (PET) might play will also be examined. New optical technologies also hold promise for obtaining low cost, yet valuable physiological data from optically accessible sites. The review is organised by traditional outcome parameters: local response, local control and progression-free or overall survival. Included in the review is a discussion of future directions for this type of translational work.

Authors
Dewhirst, MW; Thrall, DE; Palmer, G; Schroeder, T; Vujaskovic, Z; Cecil Charles, H; Macfall, J; Wong, T
MLA Citation
Dewhirst, MW, Thrall, DE, Palmer, G, Schroeder, T, Vujaskovic, Z, Cecil Charles, H, Macfall, J, and Wong, T. "Utility of functional imaging in prediction or assessment of treatment response and prognosis following thermotherapy." Int J Hyperthermia 26.3 (2010): 283-293. (Review)
PMID
20170362
Source
pubmed
Published In
International Journal of Hyperthermia (Informa)
Volume
26
Issue
3
Publish Date
2010
Start Page
283
End Page
293
DOI
10.3109/02656730903286214

Automatic bone segmentation and alignment from MR knee images

Automatic image analysis of magnetic resonance (MR) images of the knee is simplified by bringing the knee into a reference position. While the knee is typically put into a reference position during image acquisition, this alignment will generally not be perfect. To correct for imperfections, we propose a two-step process of bone segmentation followed by elastic tissue deformation. The approach makes use of a fully-automatic segmentation of femur and tibia from T1 and T2* images. The segmentation algorithm is based on a continuous convex optimization problem, incorporating regional, and shape information. The regional terms are included from a probabilistic viewpoint, which readily allows the inclusion of shape information. Segmentation of the outer boundary of the cortical bone is encouraged by adding simple appearance-based information to the optimization problem. The resulting segmentation without the shape alignment step is globally optimal. Standard registration is problematic for knee alignment due to the distinct physical properties of the tissues constituting the knee (bone, muscle, etc.). We therefore develop an alternative alignment approach based on a simple elastic deformation model combined with strict enforcement of similarity transforms for femur and tibia based on the obtained segmentations. © 2010 Copyright SPIE - The International Society for Optical Engineering.

Authors
Shan, L; Zach, C; Styner, M; Charles, C; Niethammer, M
MLA Citation
Shan, L, Zach, C, Styner, M, Charles, C, and Niethammer, M. "Automatic bone segmentation and alignment from MR knee images." Progress in Biomedical Optics and Imaging - Proceedings of SPIE 7623.PART 1 (2010).
Source
scival
Published In
Proceedings of SPIE
Volume
7623
Issue
PART 1
Publish Date
2010
DOI
10.1117/12.841167

Trabecular morphometry by fractal signature analysis is a novel marker of osteoarthritis progression.

OBJECTIVE: To evaluate the effectiveness of using subchondral bone texture observed on a radiograph taken at baseline to predict progression of knee osteoarthritis (OA) over a 3-year period. METHODS: A total of 138 participants in the Prediction of Osteoarthritis Progression study were evaluated at baseline and after 3 years. Fractal signature analysis (FSA) of the medial subchondral tibial plateau was performed on fixed flexion radiographs of 248 nonreplaced knees, using a commercially available software tool. OA progression was defined as a change in joint space narrowing (JSN) or osteophyte formation of 1 grade according to a standardized knee atlas. Statistical analysis of fractal signatures was performed using a new model based on correlating the overall shape of a fractal dimension curve with radius. RESULTS: Fractal signature of the medial tibial plateau at baseline was predictive of medial knee JSN progression (area under the curve [AUC] 0.75, of a receiver operating characteristic curve) but was not predictive of osteophyte formation or progression of JSN in the lateral compartment. Traditional covariates (age, sex, body mass index, knee pain), general bone mineral content, and joint space width at baseline were no more effective than random variables for predicting OA progression (AUC 0.52-0.58). The predictive model with maximum effectiveness combined fractal signature at baseline, knee alignment, traditional covariates, and bone mineral content (AUC 0.79). CONCLUSION: We identified a prognostic marker of OA that is readily extracted from a plain radiograph using FSA. Although the method needs to be validated in a second cohort, our results indicate that the global shape approach to analyzing these data is a potentially efficient means of identifying individuals at risk of knee OA progression.

Authors
Kraus, VB; Feng, S; Wang, S; White, S; Ainslie, M; Brett, A; Holmes, A; Charles, HC
MLA Citation
Kraus, VB, Feng, S, Wang, S, White, S, Ainslie, M, Brett, A, Holmes, A, and Charles, HC. "Trabecular morphometry by fractal signature analysis is a novel marker of osteoarthritis progression." Arthritis Rheum 60.12 (December 2009): 3711-3722.
PMID
19950282
Source
pubmed
Published In
Arthritis and Rheumatism
Volume
60
Issue
12
Publish Date
2009
Start Page
3711
End Page
3722
DOI
10.1002/art.25012

Subregional femorotibial cartilage morphology in women--comparison between healthy controls and participants with different grades of radiographic knee osteoarthritis.

OBJECTIVE: To identify subregional differences in femorotibial cartilage morphology between healthy controls and women with different grades of radiographic knee osteoarthritis (OA). DESIGN: 158 women aged > or =40 years were studied. Weight-bearing extended anterior-posterior (AP) and Lyon schuss radiographs were obtained and the Kellgren Lawrence grade (KLG) determined. 97 women had a body mass index (BMI)< or =28, no symptoms, and were AP KLG0. 61 women had a BMI> or =30, symptoms in the target knee, and mild (KLG2=31) to moderate (KLG3=30) medial femorotibial radiographic OA in the AP views. Coronal spoiled gradient echo water excitation sequences were acquired at 3.0 Tesla. Total plate and regional measures of cartilage morphology of the weight-bearing femorotibial joint were quantified. RESULTS: KLG2 participants displayed, on average, thicker cartilage than healthy controls in the medial femorotibial compartment (particularly anterior subregion of the medial tibia (MT) and peripheral [external, internal] subregions of the medial femur), and in the lateral femur. KLG3 participants displayed significantly thinner cartilage than KLG0 participants in the medial weight-bearing femur (central subregion), in the external subregion of the MT, and in the internal subregion of the lateral tibia. These differences were generally unaffected when possible effects of demographic covariates were considered. CONCLUSIONS: The results indicate that in femorotibial OA regional cartilage thickening and thinning may occur, dependent on the (radiographic) disease status of the joint. These changes appear to display a heterogeneous spatial pattern, where certain subregions are more strongly affected than others.

Authors
Hellio Le Graverand, M-P; Buck, RJ; Wyman, BT; Vignon, E; Mazzuca, SA; Brandt, KD; Piperno, M; Charles, HC; Hudelmaier, M; Hunter, DJ; Jackson, C; Kraus, VB; Link, TM; Majumdar, S; Prasad, PV; Schnitzer, TJ; Vaz, A; Wirth, W; Eckstein, F
MLA Citation
Hellio Le Graverand, M-P, Buck, RJ, Wyman, BT, Vignon, E, Mazzuca, SA, Brandt, KD, Piperno, M, Charles, HC, Hudelmaier, M, Hunter, DJ, Jackson, C, Kraus, VB, Link, TM, Majumdar, S, Prasad, PV, Schnitzer, TJ, Vaz, A, Wirth, W, and Eckstein, F. "Subregional femorotibial cartilage morphology in women--comparison between healthy controls and participants with different grades of radiographic knee osteoarthritis." Osteoarthritis Cartilage 17.9 (September 2009): 1177-1185.
PMID
19341831
Source
pubmed
Published In
Osteoarthritis and Cartilage
Volume
17
Issue
9
Publish Date
2009
Start Page
1177
End Page
1185
DOI
10.1016/j.joca.2009.03.008

Dynamic contrast-enhanced magnetic resonance imaging as a predictor of clinical outcome in canine spontaneous soft tissue sarcomas treated with thermoradiotherapy.

PURPOSE: This study tests whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters obtained from canine patients with soft tissue sarcomas, treated with hyperthermia and radiotherapy, are predictive of therapeutic outcome. EXPERIMENTAL DESIGN: Thirty-seven dogs with soft tissue sarcomas had DCE-MRI done before and following the first hyperthermia. Signal enhancement for tumor and reference muscle were fitted empirically, yielding a washin/washout rate for the contrast agent and tumor area under the signal enhancement curve (AUC) calculated from 0 to 60 seconds, 90 seconds, and the time of maximal enhancement in the reference muscle. These parameters were then compared with local tumor control, metastasis-free survival, and overall survival. RESULTS: Pretherapy rate of contrast agent washout was positively predictive of improved overall and metastasis-free survival with hazard ratio of 0.67 (P = 0.015) and 0.68 (P = 0.012), respectively. After the first hyperthermia washin rate, AUC60, AUC90, and AUCt-max were predictive of improved overall and metastasis-free survival with hazard ratio ranging from 0.46 to 0.53 (P < 0.002) and 0.44 to 0.55 (P < 0.004), respectively. DCE-MRI parameters were compared with extracellular pH and (31)P MR spectroscopy results (previously published) in the same patients showing a correlation. This suggested that an increase in perfusion after therapy was effective in eliminating excess acid from the tumor. CONCLUSIONS: This study shows that DCE-MRI has utility predicting overall and metastasis-free survival in canine patients with soft tissue sarcomas. To our knowledge, this is the first time that DCE-MRI parameters are predictive of clinical outcome for soft tissue sarcomas.

Authors
Viglianti, BL; Lora-Michiels, M; Poulson, JM; Lan, L; Yu, D; Sanders, L; Craciunescu, O; Vujaskovic, Z; Thrall, DE; Macfall, J; Charles, CH; Wong, T; Dewhirst, MW
MLA Citation
Viglianti, BL, Lora-Michiels, M, Poulson, JM, Lan, L, Yu, D, Sanders, L, Craciunescu, O, Vujaskovic, Z, Thrall, DE, Macfall, J, Charles, CH, Wong, T, and Dewhirst, MW. "Dynamic contrast-enhanced magnetic resonance imaging as a predictor of clinical outcome in canine spontaneous soft tissue sarcomas treated with thermoradiotherapy." Clin Cancer Res 15.15 (August 1, 2009): 4993-5001.
PMID
19622579
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
15
Issue
15
Publish Date
2009
Start Page
4993
End Page
5001
DOI
10.1158/1078-0432.CCR-08-2222

Hyperthermia MRI temperature measurement: evaluation of measurement stabilisation strategies for extremity and breast tumours.

PURPOSE: MR thermometry using the proton resonance frequency shift (PRFS) method has been used to measure temperature changes during clinical hyperthermia treatment. However, frequency drift of the MRI system can add large errors to the measured temperature change. These drifts can be measured and corrected using oil references placed around the treatment region. In this study, the number and position of four or more oil references were investigated to obtain a practical approach to correct frequency drift during PRFS thermometry in phantoms and in vivo. MATERIALS AND METHODS: Experiments were performed in a 140 MHz four antenna mini-annular phased array (MAPA) heat applicator (for treatment of extremity tumours) and an applicator for heating of the breast, with symmetric and asymmetric positioning of the oil references, respectively. Temperature change PRFS images were obtained during an hour or more of measurement with no application of heat. Afterwards, errors in calculating temperature change due to system drift were quantified with and without various oil reference correction arrangements. RESULTS: Results showed good temperature correction in phantoms and in a human leg, with average errors of 0.28 degrees C and 0.94 degrees C respectively. There was further improvement in the leg when using eight or more oil references, reducing the average error to 0.44 degrees C, while the phantoms showed no significant improvement. CONCLUSIONS: These results indicate that oil reference correction performs well in vivo, and that eight references can improve the correction by up to 0.5 degrees C compared to four references.

Authors
Wyatt, C; Soher, B; Maccarini, P; Charles, HC; Stauffer, P; Macfall, J
MLA Citation
Wyatt, C, Soher, B, Maccarini, P, Charles, HC, Stauffer, P, and Macfall, J. "Hyperthermia MRI temperature measurement: evaluation of measurement stabilisation strategies for extremity and breast tumours." Int J Hyperthermia 25.6 (2009): 422-433.
PMID
19925322
Source
pubmed
Published In
International Journal of Hyperthermia (Informa)
Volume
25
Issue
6
Publish Date
2009
Start Page
422
End Page
433
DOI
10.1080/02656730903133762

Time-lapse mapping of cortical changes in schizophrenia with different treatments

Using time-lapse maps, we visualized the dynamics of schizophrenia progression, revealing spreading cortical changes that depend on the type of antipsychotic treatment. Dynamic, 4-dimensional models of disease progression were created from 4 repeated high-resolution brain magnetic resonance imaging scans of 36 first-episode schizophrenia patients (30 men/6 women; mean age: 24.2 ± 5.1 SD years) randomized to haloperidol (HAL) (n = 15) or olanzapine (OLZ) treatment (n = 21), imaged at baseline, 3, 6, and 12 months (144 scans). Based on surface-based cortical models and point-by-point measures of gray matter volume, we generated time-lapse maps for each treatment. Disease trajectories differed for atypical versus typical neuroleptic drugs. A rapidly advancing parietal-to-frontal deficit trajectory, in HAL-treated patients, mirrored normal cortical maturation but greatly intensified. The disease trajectory advanced even after symptom normalization, involving the frontal cortex within 12 months with typical drug treatment. Areas with fastest tissue loss shifted anteriorly in the first year of psychosis. This trajectory was not seen with OLZ. Whether this association reflects either reduced neurotoxicity or neuroprotection cannot be addressed with neuroimaging; changes may relate to glial rather than neural components. These maps revise current models of schizophrenia progression; due to power limitations, the findings require confirmation in a sample large enough to model group × time interactions.

Authors
Thompson, PM; Bartzokis, G; Hayashi, KM; Klunder, AD; Lu, PH; Edwards, N; Hong, MS; Yu, M; Geaga, JA; Toga, AW; Charles, C; Perkins, DO; McEvoy, J; Hamer, RM; Tohen, M; Tollefson, GD; Lieberman, JA
MLA Citation
Thompson, PM, Bartzokis, G, Hayashi, KM, Klunder, AD, Lu, PH, Edwards, N, Hong, MS, Yu, M, Geaga, JA, Toga, AW, Charles, C, Perkins, DO, McEvoy, J, Hamer, RM, Tohen, M, Tollefson, GD, and Lieberman, JA. "Time-lapse mapping of cortical changes in schizophrenia with different treatments." Cerebral Cortex 19.5 (2009): 1107-1123.
PMID
18842668
Source
scival
Published In
Cerebral Cortex
Volume
19
Issue
5
Publish Date
2009
Start Page
1107
End Page
1123
DOI
10.1093/cercor/bhn152

Clinical utility of magnetic resonance thermal imaging (MRTI) for realtime guidance of deep hyperthermia

A critical need has emerged for volumetric thermometry to visualize 3D temperature distributions in real time during deep hyperthermia treatments used as an adjuvant to radiation or chemotherapy for cancer. For the current effort, magnetic resonance thermal imaging (MRTI) is used to measure 2D temperature rise distributions in four cross sections of large extremity soft tissue sarcomas during hyperthermia treatments. Novel hardware and software techniques aredescribed which improve the signal to noise ratio of MR images, minimize motion artifact from circulating coupling fluids, and provide accurate high resolution volumetric thermal dosimetry. For the first 10 extremity sarcoma patients, the mean difference between MRTI region of interest and adjacent interstitial point measurements during the period of steady state temperature was 0.85°C. With 1min temporal resolution of measurements in four image planes, this noninvasive MRTI approach has demonstrated its utility for accurate monitoring and realtime steering of heat into tumors at depth in the body. © 2009 SPIE.

Authors
Stauffer, PR; Craciunescu, OI; Maccarini, PF; Wyatt, C; Arunachalam, K; Arabe, O; Stakhursky, V; Soher, B; MacFall, JR; Li, Z; Joines, WT; Rangarao, S; Cheng, KS; Das, SK; Martins, CD; Charles, C; Dewhirst, MW; Wong, T; Jones, E; Vujaskovic, Z
MLA Citation
Stauffer, PR, Craciunescu, OI, Maccarini, PF, Wyatt, C, Arunachalam, K, Arabe, O, Stakhursky, V, Soher, B, MacFall, JR, Li, Z, Joines, WT, Rangarao, S, Cheng, KS, Das, SK, Martins, CD, Charles, C, Dewhirst, MW, Wong, T, Jones, E, and Vujaskovic, Z. "Clinical utility of magnetic resonance thermal imaging (MRTI) for realtime guidance of deep hyperthermia." Progress in Biomedical Optics and Imaging - Proceedings of SPIE 7181 (2009).
PMID
24224074
Source
scival
Published In
Proceedings of SPIE
Volume
7181
Publish Date
2009
DOI
10.1117/12.812188

Precision of 3.0 Tesla quantitative magnetic resonance imaging of cartilage morphology in a multicentre clinical trial.

OBJECTIVE: Quantitative MRI (qMRI) of cartilage morphology is a promising tool for disease-modifying osteoarthritis drug (DMOAD) development. Recent studies at single sites have indicated that measurements at 3.0 Tesla (T) are more reproducible (precise) than those at 1.5 T. Precision errors and stability in multicentre studies with imaging equipment from various vendors have, however, not yet been evaluated. METHODS: A total of 158 female participants (97 Kellgren and Lawrence grade (KLG) 0, 31 KLG 2 and 30 KLG 3) were imaged at 7 clinical centres using Siemens Magnetom Trio and GE Signa Excite magnets. Double oblique coronal acquisitions were obtained at baseline and at 3 months, using water excitation spoiled gradient echo sequences (1.0x0.31x0.31 mm3 resolution). Segmentation of femorotibial cartilage morphology was performed using proprietary software (Chondrometrics GmbH, Ainring, Germany). RESULTS: The precision error (root mean square coefficient of variation (RMS CV)%) for cartilage thickness/volume measurements ranged from 2.1%/2.4% (medial tibia) to 2.9%/3.3% (lateral weight-bearing femoral condyle) across all participants. No significant differences in precision errors were observed between KLGs, imaging sites, or scanner manufacturers/types. Mean differences between baseline and 3 months ranged from <0.1% (non-significant) in the medial to 0.94% (p<0.01) in the lateral femorotibial compartment, and were 0.33% (p<0.02) for the total femorotibial subchondral bone area. CONCLUSIONS: qMRI performed at 3.0 T provides highly reproducible measurements of cartilage morphology in multicentre clinical trials with equipment from different vendors. The technology thus appears sufficiently robust to be recommended for large-scale multicentre trials.

Authors
Eckstein, F; Buck, RJ; Burstein, D; Charles, HC; Crim, J; Hudelmaier, M; Hunter, DJ; Hutchins, G; Jackson, C; Kraus, VB; Lane, NE; Link, TM; Majumdar, LS; Mazzuca, S; Prasad, PV; Schnitzer, TJ; Taljanovic, MS; Vaz, A; Wyman, B; Le Graverand, M-PH; A9001140 Study Group,
MLA Citation
Eckstein, F, Buck, RJ, Burstein, D, Charles, HC, Crim, J, Hudelmaier, M, Hunter, DJ, Hutchins, G, Jackson, C, Kraus, VB, Lane, NE, Link, TM, Majumdar, LS, Mazzuca, S, Prasad, PV, Schnitzer, TJ, Taljanovic, MS, Vaz, A, Wyman, B, Le Graverand, M-PH, and A9001140 Study Group, . "Precision of 3.0 Tesla quantitative magnetic resonance imaging of cartilage morphology in a multicentre clinical trial." Ann Rheum Dis 67.12 (December 2008): 1683-1688.
PMID
18283054
Source
pubmed
Published In
Annals of the rheumatic diseases
Volume
67
Issue
12
Publish Date
2008
Start Page
1683
End Page
1688
DOI
10.1136/ard.2007.076919

Performance of a non-fluoroscopically assisted substitute for the Lyon schuss knee radiograph: quality and reproducibility of positioning and sensitivity to joint space narrowing in osteoarthritic knees.

OBJECTIVE: This study evaluated the longitudinal performance of a modified Lyon schuss (LS) knee examination in the detection of radiographic joint space narrowing (JSN) in knees with osteoarthritis (OA). The modified LS exam entails two to four iterative acquisitions with empirically adjusted angulation of the X-ray beam to achieve superimposition of the anterior and posterior margins of the medial tibial plateau (MTP), a marker of parallel radioanatomic alignment that the original LS exam achieves with fluoroscopically guided beam angulation. METHODS: Seventy-four obese women with symptomatic knee OA underwent LS and fixed-flexion (FF, caudal 10 degrees beam angulation) X-ray exams at baseline and 1 year later. For 47 subjects, beam angulation for both LS exams was guided by fluoroscopy. For 27 subjects, the modified LS exam was performed at one or both times. Modified and original LS procedures were evaluated relative to concurrent FF radiographs with respect to the inter-margin distance (IMD) at the MTP midpoint (quality and reproducibility of alignment) and sensitivity to JSN. RESULTS: Compared to FF radiographs, modified LS radiographs afforded a smaller mean IMD at baseline (0.89 vs 2.06 mm, P=0.002), more reproducible IMD (mean change=0.49 vs 0.91 mm, P=0.007) and more rapid JSN (mean=0.25 vs 0.02 mm/yr, P=0.005). These differences paralleled those observed between original LS and FF procedures with respect to baseline alignment (0.96 vs 1.94 mm, P<0.001), reproducibility of alignment (0.49 vs 1.00 mm, P<0.001) and sensitivity to JSN (0.16 vs -0.01 mm/yr, P=0.007). CONCLUSION: In clinical centers where the absence of fluoroscopy equipment precludes use of the original LS protocol, a modified procedure employing iterative, empirical adjustment of the beam angle to achieve parallel radioanatomic alignment with the MTP affords a degree of superiority over the FF protocol with respect to quality and reproducibility of positioning and sensitivity to JSN in OA knees similar to that of the original.

Authors
Mazzuca, SA; Hellio Le Graverand, M-P; Vignon, E; Hunter, DJ; Jackson, CG; Kraus, VB; Link, TM; Schnitzer, TJ; Vaz, A; Charles, HC
MLA Citation
Mazzuca, SA, Hellio Le Graverand, M-P, Vignon, E, Hunter, DJ, Jackson, CG, Kraus, VB, Link, TM, Schnitzer, TJ, Vaz, A, and Charles, HC. "Performance of a non-fluoroscopically assisted substitute for the Lyon schuss knee radiograph: quality and reproducibility of positioning and sensitivity to joint space narrowing in osteoarthritic knees." Osteoarthritis Cartilage 16.12 (December 2008): 1555-1559.
PMID
18515156
Source
pubmed
Published In
Osteoarthritis and Cartilage
Volume
16
Issue
12
Publish Date
2008
Start Page
1555
End Page
1559
DOI
10.1016/j.joca.2008.04.010

Head-to-head comparison of the Lyon Schuss and fixed flexion radiographic techniques. Long-term reproducibility in normal knees and sensitivity to change in osteoarthritic knees.

OBJECTIVE: The Lyon Schuss (LS) and fixed flexion (FF) views of the knee are superior to a conventional standing anteroposterior view in evaluating joint space narrowing (JSN) in osteoarthritis (OA). Both position the knee identically but only the LS aligns the medial tibial plateau (MTP) with the x-ray beam fluoroscopically. The present study provides the first head-to-head comparison of the LS and FF views. METHODS: At baseline and 12 months, 62 OA and 99 control knees were imaged twice on the same day with LS and FF views. Minimum joint space width (mJSW) was measured by computer and MTP alignment was assessed from the distance between anterior and posterior margins of the MTP (intermargin distance, IMD). Reproducibility of measurements of mJSW and sensitivity to change were evaluated. RESULTS: In normal knees, JSW did not vary over 12 months with either view. In OA knees, 12-month mJSN was 0.22 (0.43) mm with the LS view and -0.01 (0.46) mm with the FF view (p = 0.0002 and p = 0.92, respectively). Mean IMD was only half as large in LS as in FF views (0.9 (0.5) mm vs 1.9 (1.2) mm, p<0.0001). CONCLUSIONS: LS and FF radiographs offer similar reproducibility in JSW measurement. However, presumably due to its superiority in aligning the MTP, the LS view is much more sensitive to JSN in OA knees.

Authors
Le Graverand, M-PH; Vignon, EP; Brandt, KD; Mazzuca, SA; Piperno, M; Buck, R; Charles, HC; Hunter, DJ; Jackson, CG; Kraus, VB; Link, TM; Schnitzer, TJ; Vaz, A; Wyman, B
MLA Citation
Le Graverand, M-PH, Vignon, EP, Brandt, KD, Mazzuca, SA, Piperno, M, Buck, R, Charles, HC, Hunter, DJ, Jackson, CG, Kraus, VB, Link, TM, Schnitzer, TJ, Vaz, A, and Wyman, B. "Head-to-head comparison of the Lyon Schuss and fixed flexion radiographic techniques. Long-term reproducibility in normal knees and sensitivity to change in osteoarthritic knees." Ann Rheum Dis 67.11 (November 2008): 1562-1566.
PMID
18258709
Source
pubmed
Published In
Annals of the rheumatic diseases
Volume
67
Issue
11
Publish Date
2008
Start Page
1562
End Page
1566
DOI
10.1136/ard.2007.077834

Hyperoxia-induced decrease in organ blood flow [10]

Authors
Forkner, IF; Piantadosi, CA; Charles, HC; Scafetta, N; Moon, RE
MLA Citation
Forkner, IF, Piantadosi, CA, Charles, HC, Scafetta, N, and Moon, RE. "Hyperoxia-induced decrease in organ blood flow [10]." Anesthesiology 108.1 (2008): 169-170.
Source
scival
Published In
Anesthesiology
Volume
108
Issue
1
Publish Date
2008
Start Page
169
End Page
170
DOI
10.1097/01.anes.0000296643.13634.41

In reply (Anesthesiology (2008) 108, (169-170))

Authors
Forkner, IF; Piantadosi, CA; Charles, HC; Scafetta, N; Moon, RE
MLA Citation
Forkner, IF, Piantadosi, CA, Charles, HC, Scafetta, N, and Moon, RE. "In reply (Anesthesiology (2008) 108, (169-170))." Anesthesiology 108.3 (2008): 546--.
Source
scival
Published In
Anesthesiology
Volume
108
Issue
3
Publish Date
2008
Start Page
546-

Optimization of the fixed-flexion knee radiograph.

PURPOSE: To develop a user-friendly method of achieving optimal radiographs for measurement of joint space width of the knee with minimal radiation exposure. In order to accomplish this the X-ray technologist must (1) be able to identify the anterior and posterior rims of the tibial plateau at a variety of X-ray head angles and (2) be able to choose the direction to adjust the head angle to get a better view based on the criteria for acceptable radiographs. METHODS: We have developed a training manual and materials to instruct investigators and radiology technologists in a method that uses a commercially available Plexiglas positioning frame (Synaflexer) and standard X-ray equipment to achieve optimal X-rays with regard to tibial plateau alignment of the knee. This should be accomplished with four or fewer radiographs. RESULTS: Optimized radiographs for joint space width measurements are achieved without the need for fluoroscopy or foot maps. CONCLUSIONS: This method is readily understood and instituted by radiology technologists in the field.

Authors
Charles, HC; Kraus, VB; Ainslie, M; Hellio Le Graverand-Gastineau, M-P
MLA Citation
Charles, HC, Kraus, VB, Ainslie, M, and Hellio Le Graverand-Gastineau, M-P. "Optimization of the fixed-flexion knee radiograph." Osteoarthritis Cartilage 15.11 (November 2007): 1221-1224.
PMID
17977754
Source
pubmed
Published In
Osteoarthritis and Cartilage
Volume
15
Issue
11
Publish Date
2007
Start Page
1221
End Page
1224
DOI
10.1016/j.joca.2007.05.012

Predicting memory decline in normal elderly: genetics, MRI, and cognitive reserve.

Major predictors of Alzheimer's disease (AD) include apolipoprotein E (APOE)-epsilon4, hippocampal atrophy on magnetic resonance imaging (MRI), and memory dysfunction prior to diagnosis. We examined 159 normal elderly subjects with MRI and the California Verbal Learning Test (CVLT); 84 returned for longitudinal follow-up 5 years later. Analyses at baseline revealed significant variance in hippocampal volume accounted for by cerebral volume and age but not by APOE isoform. However, interactions involving APOE isoform and laterality were observed. As hypothesized, an APOE x time interaction was revealed for CVLT long-delay free recall: APOE-epsilon3/4 subjects had significantly poorer performance than APOE-epsilon3/3 subjects at follow-up. Forward stepwise multiple regression analysis predicting follow-up long-delay free recall selected baseline recall, followed by number of APOE-epsilon4 alleles, followed by left-hippocampal volume. Age and sex did not enter into the model. We conclude that APOE-epsilon4 predicts longitudinal memory decline in healthy controls and that MRI morphometry of hippocampus adds slightly to predictive value.

Authors
Tupler, LA; Krishnan, KRR; Greenberg, DL; Marcovina, SM; Payne, ME; MacFall, JR; Charles, HC; Doraiswamy, PM
MLA Citation
Tupler, LA, Krishnan, KRR, Greenberg, DL, Marcovina, SM, Payne, ME, MacFall, JR, Charles, HC, and Doraiswamy, PM. "Predicting memory decline in normal elderly: genetics, MRI, and cognitive reserve." Neurobiol Aging 28.11 (November 2007): 1644-1656.
PMID
16916565
Source
pubmed
Published In
Neurobiology of Aging
Volume
28
Issue
11
Publish Date
2007
Start Page
1644
End Page
1656
DOI
10.1016/j.neurobiolaging.2006.07.001

Quantitative imaging of cartilage morphology at 3.0 Tesla in the presence of gadopentate dimeglumine (Gd-DTPA).

MRI-based cartilage morphometry was previously validated in the absence of gadopentate dimeglumine (Gd-DTPA). However, Gd-DTPA is required for compositional (proteoglycan) imaging using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC). Therefore, the effect of Gd-DTPA on cartilage morphometry was studied. A total of 165 female participants (67 with and 98 without osteoarthritis [OA]) were imaged at 3.0 Tesla before and 2 hr after intravenous Gd-DTPA injection. Flip angles in post-Gd-DTPA scans varied between 12 degrees and 35 degrees . Cartilage volume and thickness of post- vs. pre-Gd-DTPA scans showed intraclass correlation coefficients (ICCs) of 0.85 > or = r > or = 0.95, mean differences between -2.1% and +1.1%, and standard deviations (SDs) of differences between 4.7% and 9.2%. Mixed-effect models found no consistent impact of flip angle and OA status on post- vs. pre-Gd-DTPA differences. Accurate morphological measurements of cartilage can be obtained after Gd-DTPA injection, allowing compositional and morphological imaging to be combined into one session.

Authors
Eckstein, F; Buck, RJ; Wyman, BT; Kotyk, JJ; Le Graverand, M-PH; Remmers, AE; Evelhoch, JL; Hudelmaier, M; Charles, HC
MLA Citation
Eckstein, F, Buck, RJ, Wyman, BT, Kotyk, JJ, Le Graverand, M-PH, Remmers, AE, Evelhoch, JL, Hudelmaier, M, and Charles, HC. "Quantitative imaging of cartilage morphology at 3.0 Tesla in the presence of gadopentate dimeglumine (Gd-DTPA)." Magn Reson Med 58.2 (August 2007): 402-406.
PMID
17654593
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
58
Issue
2
Publish Date
2007
Start Page
402
End Page
406
DOI
10.1002/mrm.21290

Effect of rivastigmine on delay to diagnosis of Alzheimer's disease from mild cognitive impairment: the InDDEx study.

OBJECTIVE: To assess the effect of rivastigmine in patients with mild cognitive impairment (MCI) on the time to clinical diagnosis of Alzheimer's disease (AD) and the rate of cognitive decline. METHODS: The study was a double-blind, randomised, placebo-controlled trial of up to 48 months. All patients had MCI operationally defined by having cognitive symptoms, a global clinical dementia rating stage of 0.5, a score of less than 9 on the New York University delayed paragraph recall test, and by not meeting the diagnostic criteria for AD. Primary efficacy variables were time to clinical diagnosis of AD, and change in performance on a cognitive test battery. This study is registered with the US National Institutes of Health clinical trials database (ClinicalTrials.gov), number NCT00000174. FINDINGS: Of 1018 study patients enrolled, 508 were randomly assigned to rivastigmine and 510 to placebo; 17.3% of patients on rivastigmine and 21.4% on placebo progressed to AD (hazard ratio 0.85 [95% CI 0.64-1.12]; p=0.225). There was no significant difference between the rivastigmine and placebo groups on the standardised Z score for the cognitive test battery measured as mean change from baseline to endpoint (-0.10 [95% CI -0.63 to 0.44], p=0.726). Serious adverse events were reported by 141 (27.9%) rivastigmine-treated patients and 155 (30.5%) patients on placebo; adverse events of all types were reported by 483 (95.6%) rivastigmine-treated patients and 472 (92.7%) placebo-treated patients. The predominant adverse events were cholinergic: the frequencies of nausea, vomiting, diarrhoea, and dizziness were two to four times higher in the rivastigmine group than in the placebo group. INTERPRETATION: There was no significant benefit of rivastigmine on the progression rate to AD or on cognitive function over 4 years. The overall rate of progression from MCI to AD in this randomised clinical trial was much lower than predicted. Rivastigmine treatment was not associated with any significant safety concerns.

Authors
Feldman, HH; Ferris, S; Winblad, B; Sfikas, N; Mancione, L; He, Y; Tekin, S; Burns, A; Cummings, J; del Ser, T; Inzitari, D; Orgogozo, J-M; Sauer, H; Scheltens, P; Scarpini, E; Herrmann, N; Farlow, M; Potkin, S; Charles, HC; Fox, NC; Lane, R
MLA Citation
Feldman, HH, Ferris, S, Winblad, B, Sfikas, N, Mancione, L, He, Y, Tekin, S, Burns, A, Cummings, J, del Ser, T, Inzitari, D, Orgogozo, J-M, Sauer, H, Scheltens, P, Scarpini, E, Herrmann, N, Farlow, M, Potkin, S, Charles, HC, Fox, NC, and Lane, R. "Effect of rivastigmine on delay to diagnosis of Alzheimer's disease from mild cognitive impairment: the InDDEx study." Lancet Neurol 6.6 (June 2007): 501-512.
PMID
17509485
Source
pubmed
Published In
The Lancet Neurology
Volume
6
Issue
6
Publish Date
2007
Start Page
501
End Page
512
DOI
10.1016/S1474-4422(07)70109-6

Extracellular pH and P-31 magnetic resonance spectroscopic variables are related to outcome in canine soft tissue sarcomas treated with thermoradiotherapy.

PURPOSE: The objective was to test whether tumor pH and (31)P magnetic resonance spectroscopic end points were related to treatment outcome in pet canine patients with spontaneous soft tissue sarcomas treated with thermoradiotherapy. EXPERIMENTAL DESIGN: Forty-two dogs with evaluable (31)P magnetic resonance spectroscopic end points and pH data were included in this study. Tumor variables (grade and volume), extracellular pH (pHe), T(2) relaxation times, intracellular pH, and selected phosphometabolite ratios were examined for correlation with clinical outcome. RESULTS: From 39 dogs, pHe was a predictor of metastasis-free survival (MFS), with hazard ratio (HR, 0.29; P = 0.005) and overall survival (OS) with (HR, 0.36; P = 0.013). Tumor volume (>19 cm(3)) was related to MFS (HR, 2.14; P = 0.04), time to local failure (HR, 3.4; P = 0.025), and OS (HR, 2.27; P = 0.03). There was no association between T(2) or intracellular pH and clinical outcome. Tumor grade (high versus low/intermediate) and phosphodiester/betaATP ratio were identified as significant predictors for MFS, with (HR, 2.66; P = 0.009) and (HR, 0.75; P = 0.027), respectively, and as predictors of OS with (HR, 2.66; P = 0.009) and (HR, 0.76; P = 0.03), respectively. The phosphodiester/phosphocreatinine ratio predicted time to local failure (HR, 1.24; P = 0.017). CONCLUSIONS: pHe was predictive of metastasis and OS in canine spontaneous sarcomas. To our knowledge, this is the first time that pHe has been shown to be predictive of clinical outcome. The results suggest that additional studies should be considered evaluating the prognostic significance of this variable. Phospholipid resonances, related to membrane metabolism, were related to clinical outcome, confirming recent results reported in human patients with soft tissue sarcomas treated with thermoradiotherapy.

Authors
Lora-Michiels, M; Yu, D; Sanders, L; Poulson, JM; Azuma, C; Case, B; Vujaskovic, Z; Thrall, DE; Charles, HC; Dewhirst, MW
MLA Citation
Lora-Michiels, M, Yu, D, Sanders, L, Poulson, JM, Azuma, C, Case, B, Vujaskovic, Z, Thrall, DE, Charles, HC, and Dewhirst, MW. "Extracellular pH and P-31 magnetic resonance spectroscopic variables are related to outcome in canine soft tissue sarcomas treated with thermoradiotherapy." Clin Cancer Res 12.19 (October 1, 2006): 5733-5740.
PMID
17020978
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
12
Issue
19
Publish Date
2006
Start Page
5733
End Page
5740
DOI
10.1158/1078-0432.CCR-05-2669

In vivo 31P MR spectral patterns and reproducibility in cancer patients studied in a multi-institutional trial.

The standardization and reproducibility of techniques required to acquire anatomically localized 31P MR spectra non-invasively while studying tumors in cancer patients in a multi-institutional group at 1.5 T are reported. This initial group of patients was studied from 1995 to 2000 to test the feasibility of acquiring in vivo localized 31P MRS in clinical MR spectrometers. The cancers tested were non-Hodgkin's lymphomas, sarcomas of soft tissue and bone, breast carcinomas and head and neck carcinomas. The best accrual and spectral quality were achieved with the non-Hodgkin's lymphomas. The initial analysis of the spectral values of the sum of phosphoethanolamine plus phosphocholine normalized by the content of nucleotide triphosphates in a homogeneous sample of 32 NHL patients studied by in vivo (31)P MRS showed good reproducibility among different institutions. No statistical differences were found between the institution with the largest number of cases accrued and the rest of the multi-institutional NHL data (2.28 +/- 0.64, mean +/- standard error; n = 17, vs 2.08 +/- 0.14, n = 15). The preliminary data reported demonstrate that the institutions involved in this trial are obtaining reproducible 31P MR spectroscopic data non-invasively from human tumors. This is a fundamental prerequisite for the international cooperative group to be able to demonstrate the clinical value of the normalized determination of phosphoethanolamine plus phosphocholine by 31P MRS as predictor for treatment response in cancer patients.

Authors
Arias-Mendoza, F; Payne, GS; Zakian, KL; Schwarz, AJ; Stubbs, M; Stoyanova, R; Ballon, D; Howe, FA; Koutcher, JA; Leach, MO; Griffiths, JR; Heerschap, A; Glickson, JD; Nelson, SJ; Evelhoch, JL; Charles, HC; Brown, TR
MLA Citation
Arias-Mendoza, F, Payne, GS, Zakian, KL, Schwarz, AJ, Stubbs, M, Stoyanova, R, Ballon, D, Howe, FA, Koutcher, JA, Leach, MO, Griffiths, JR, Heerschap, A, Glickson, JD, Nelson, SJ, Evelhoch, JL, Charles, HC, and Brown, TR. "In vivo 31P MR spectral patterns and reproducibility in cancer patients studied in a multi-institutional trial." NMR Biomed 19.4 (June 2006): 504-512.
PMID
16763965
Source
pubmed
Published In
Nmr in Biomedicine
Volume
19
Issue
4
Publish Date
2006
Start Page
504
End Page
512
DOI
10.1002/nbm.1057

A review of 1H MR spectroscopy findings in Alzheimer's disease.

Hydrogen-1 MR spectroscopy (MRS) studies demonstrate metabolic differences between patients who have Alzheimer's disease (AD) and cognitive normal age-matched controls. Clinical MRS also shows regional variations in metabolites between patients who have AD and those who have other dementias. Single-voxel and volumetric standard MRS techniques and automated data processing software are available for clinical MR scanners. Improvements in specificity and sensitivity of AD diagnosis, using MRS techniques as an adjunct to clinical imaging, are under evaluation. Multiparametric data analyses show, however, that metabolite changes correlate with in-vitro, postmortem, and metabolic changes and to changes in or predictions of cognitive scores.

Authors
Soher, BJ; Doraiswamy, PM; Charles, HC
MLA Citation
Soher, BJ, Doraiswamy, PM, and Charles, HC. "A review of 1H MR spectroscopy findings in Alzheimer's disease." Neuroimaging Clin N Am 15.4 (November 2005): 847-xi. (Review)
PMID
16443495
Source
pubmed
Published In
Neuroimaging Clinics of North America
Volume
15
Issue
4
Publish Date
2005
Start Page
847
End Page
xi
DOI
10.1016/j.nic.2005.09.013

Accuracy and precision of quantitative assessment of cartilage morphology by magnetic resonance imaging at 3.0T.

OBJECTIVE: Quantitative magnetic resonance imaging (MRI) of articular cartilage represents a powerful tool in osteoarthritis (OA) research, but has so far been confined to a field strength of 1.5T. The aim of this study was to evaluate the precision of quantitative MRI assessments of human cartilage morphology at 3.0T and to correlate the measurements at 3.0T with validated measurements at 1.5T. METHODS: MR images of the knee of 15 participants with OA and 15 healthy control subjects were acquired using Siemens 1.5T and 3.0T scanners. Double oblique coronal scans were obtained at 1.5T with a 1.5-mm partition thickness, at 3.0T with a 1.5-mm partition thickness, and at 3.0T with a 1.0-mm partition thickness. Cartilage volume, thickness, and surface area of the femorotibial cartilage plates were quantified using proprietary software. RESULTS: For 1.5-mm partition thickness at 1.5T, the precision error was 3.0% and 2.6% for cartilage volume and cartilage thickness, respectively. The error was smaller for a 1.5-mm partition thickness at 3.0T (2.6% and 2.5%) and still smaller for a 1.0-mm partition thickness at 3.0T (2.1% and 2.0%). Correlation coefficients between values obtained at 3.0T and 1.5T were high (r > or = 0.96), with no significant deviation between the two field strengths. CONCLUSION: Quantitative MRI measurement of cartilage morphology at 3.0T (partition thickness 1 mm) was found to be accurate and tended to be more reproducible than at 1.5T (partition thickness 1.5 mm). Imaging at 3.0T may therefore provide superior ability to detect changes in cartilage status over time and to determine responses to treatment with structure-modifying drugs.

Authors
Eckstein, F; Charles, HC; Buck, RJ; Kraus, VB; Remmers, AE; Hudelmaier, M; Wirth, W; Evelhoch, JL
MLA Citation
Eckstein, F, Charles, HC, Buck, RJ, Kraus, VB, Remmers, AE, Hudelmaier, M, Wirth, W, and Evelhoch, JL. "Accuracy and precision of quantitative assessment of cartilage morphology by magnetic resonance imaging at 3.0T." Arthritis Rheum 52.10 (October 2005): 3132-3136.
PMID
16200592
Source
pubmed
Published In
Arthritis and Rheumatism
Volume
52
Issue
10
Publish Date
2005
Start Page
3132
End Page
3136
DOI
10.1002/art.21348

Relation between pO2, 31P magnetic resonance spectroscopy parameters and treatment outcome in patients with high-grade soft tissue sarcomas treated with thermoradiotherapy.

PURPOSE: In a prior study, the combination of (31)P magnetic resonance spectroscopy (MRS)-based intracellular pH (pHi) and T2 relaxation time was highly predictive of the pathologic complete response (pCR) rate in a small series of patients with soft tissue sarcomas (STSs) treated with thermoradiotherapy. Changes in the magnetic resonance metabolite ratios and pO(2) were related to the pCR rate. Hypoxia also correlated with a greater likelihood for the development of metastases. Because of the limited number of patients in the prior series, we initiated this study to determine whether the prior observations were repeatable and whether (31)P MRS lipid-related resonances were related to a propensity for metastasis. METHODS AND MATERIALS: Patients with high-grade STSs were enrolled in an institutional review board-approved Phase II thermoradiotherapy trial. All tumors received daily external beam radiotherapy (1.8-2.0 Gy, five times weekly) to a total dose of 30-50 Gy. Hyperthermia followed radiotherapy by <1 h and was given two times weekly. Tumors were resected 4-6 weeks after radiotherapy completion. The MRS/MRI parameters included (31)P metabolite ratios, pHi, and T2 relaxation time. The median pO(2) and hypoxic fraction were determined using pO(2) histography. Comparisons between experimental endpoints and the pCR rate and metastasis-free and overall survival were made. RESULTS: Of 35 patients, 21 and 28 had reportable pretreatment MRS/MRI and pO(2) data, respectively. The cutpoints for a previously tested receiver operating curve for a pCR were T2 = 100 and pHi = 7.3. In the current series, few tumors fell below the cutpoints so validation was not possible. The phosphodiester (PDE)/inorganic phosphate (Pi) ratio and hypoxic fraction correlated inversely with the pCR rate in the current series (Spearman correlation coefficient -0.51, p = 0.017; odds ratio of percentage of necrosis > or =95% = 0.01 for a 1% increase in the hypoxic fraction; Wald p = 0.036). The pretreatment phosphomonoester (PME)/Pi ratio also correlated inversely with the pCR rate (odds ratio of percentage of necrosis > or =95% = 0.06 for pretreatment PME/Pi ratio >0.8 vs. < or =0.8, Wald p = 0.023). The pretreatment PME/PDE ratio correlated strongly with metastasis-free survival and overall survival (p = 0.012 and hazard ratio = 5.8, and p = 0.038 and hazard ratio = 6.75, respectively). CONCLUSION: The dual parameter model containing pHi and T2 to predict the pCR in STSs treated with thermoradiotherapy was not verified. However, other parameters were statistically significant, including the PDE/Pi ratio and hypoxic fraction. These relationships may have interfered with our ability to obtain the pCR rate predicted by thermal doses achieved in these patients. The relationship between the PME/PDE ratio and metastasis-free and overall survival was provocative, but requires additional study to verify its predictive capability. Currently, 50% of all STS patients with high-grade tumors develop distant metastasis even when excellent local control is achieved. Parameters that could help select for patients who need adjuvant chemotherapy could have significant clinical benefit.

Authors
Dewhirst, MW; Poulson, JM; Yu, D; Sanders, L; Lora-Michiels, M; Vujaskovic, Z; Jones, EL; Samulski, TV; Powers, BE; Brizel, DM; Prosnitz, LR; Charles, HC
MLA Citation
Dewhirst, MW, Poulson, JM, Yu, D, Sanders, L, Lora-Michiels, M, Vujaskovic, Z, Jones, EL, Samulski, TV, Powers, BE, Brizel, DM, Prosnitz, LR, and Charles, HC. "Relation between pO2, 31P magnetic resonance spectroscopy parameters and treatment outcome in patients with high-grade soft tissue sarcomas treated with thermoradiotherapy." Int J Radiat Oncol Biol Phys 61.2 (February 1, 2005): 480-491.
PMID
15667971
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
61
Issue
2
Publish Date
2005
Start Page
480
End Page
491
DOI
10.1016/j.ijrobp.2004.06.211

Duration of illness and treatment effects on hippocampal volume in male patients with schizophrenia

Background: Reduced hippocampal volume is a consistently described structural abnormality in schizophrenia but its cause and timing are not known. Aims: To examine the relationship of duration of schizophrenic illness and treatment effects with hippocampal volumes. Method: Quantitative 1.5 T magnetic resonance imaging brain scans of young male patients in the early stage of schizophrenic illness were compared with those of chronically ill older patients. Scans were also acquired for controls matched to both patient groups for age and handedness. Duration of illness was recorded and severity of symptoms assessed with the Positive and Negative Syndrome Scale. Results: The patients with schizophrenia had smaller hippocampal volumes than the controls. The volume reduction was larger in older patients than in young, compared with age-matched controls. In the early illness group atypical antipsychotics rather than haloperidol were associated with larger hippocampal volumes even after controlling for differences in illness severity. Conclusions: The greater reduction of hippocampal volume in people with chronic v. early illness, after controlling for illness severity and age, supports the hypothesis of progressive hippocampal reduction in males with schizophrenia. Atypical antipsychotics early in illness may protect against this.

Authors
Chakos, MH; Schobel, SA; Gu, H; Gerig, G; Bradford, D; Charles, C; Lieberman, JA
MLA Citation
Chakos, MH, Schobel, SA, Gu, H, Gerig, G, Bradford, D, Charles, C, and Lieberman, JA. "Duration of illness and treatment effects on hippocampal volume in male patients with schizophrenia." British Journal of Psychiatry 186.JAN. (2005): 26-31.
PMID
15630120
Source
scival
Published In
The British journal of psychiatry : the journal of mental science
Volume
186
Issue
JAN.
Publish Date
2005
Start Page
26
End Page
31
DOI
10.1192/bjp.186.1.26

Quality of life during treatment with haloperidol or olanzapine in the year following a first psychotic episode

Objectives: Schizophrenia causes significant impairments of quality of life. As treatment approaches have advanced, more attention has been given to re-integrating patients into their psychosocial environments, rather than simply monitoring psychotic symptoms. The development of the second-generation antipsychotics raised hope that these medications would provide better quality of life improvement than conventional antipsychotics. This improvement is particularly relevant early in the course of schizophrenia. Methods: To address these considerations, improvements in measures of general health and social function (determined using the SF-36) were assessed in 195 patients with first-episode schizophrenia for up to one year following randomization to either olanzapine or haloperidol in a double blind clinical trial. We hypothesized that olanzapine would demonstrate better improvement on these measures than haloperidol. In order to test this hypothesis, we used a repeated measure model with SF-36 scores as the outcome, and treatment group, time, time2, time-by-treatment group interaction, and time2-by-treatment group interaction as fixed effects. Results: Both treatments demonstrated similar changes on the SF-36. Independent of treatment, patients demonstrated significant improvements in most of the SF-36 subscales, which approached normative scores by the end of one year of treatment. Forty-six of 100 olanzapine-treated patients and 37 of 95 haloperidol-treated patients completed the one year of this study (p < .4). Conclusions: These results suggest an important initial treatment goal for patients with new onset schizophrenic disorders, namely that they can expect to recover significant quality of life and social function at least initially in treatment. © 2005 Elsevier B.V. All rights reserved.

Authors
Strakowski, SM; Johnson, JL; DelBello, MP; Hamer, RM; Green, AI; Tohen, M; Lieberman, JA; Glick, I; Patel, JK; Lieberman, J; Perkins, D; McEvoy, JP; Charles, C; Keefe, R; Zipursky, RB; Daskalakis, ZJ; Green, AI; Nemeroff, CB; Murray, R; Sharma, T; Gur, RE; Cohen, B; Centorrino, F; Kahn, RS; Goodman, W; Kuldau, J; Rothschild, AJ; Quardo, JD; Tollefson, G; Sanger, T
MLA Citation
Strakowski, SM, Johnson, JL, DelBello, MP, Hamer, RM, Green, AI, Tohen, M, Lieberman, JA, Glick, I, Patel, JK, Lieberman, J, Perkins, D, McEvoy, JP, Charles, C, Keefe, R, Zipursky, RB, Daskalakis, ZJ, Green, AI, Nemeroff, CB, Murray, R, Sharma, T, Gur, RE, Cohen, B, Centorrino, F, Kahn, RS, Goodman, W, Kuldau, J, Rothschild, AJ, Quardo, JD, Tollefson, G, and Sanger, T. "Quality of life during treatment with haloperidol or olanzapine in the year following a first psychotic episode." Schizophrenia Research 78.2-3 (2005): 161-169.
PMID
15950436
Source
scival
Published In
Schizophrenia Research
Volume
78
Issue
2-3
Publish Date
2005
Start Page
161
End Page
169
DOI
10.1016/j.schres.2005.04.017

Antipsychotic drug effects on brain morphology in first-episode psychosis

Background: Pathomorphologic brain changes occurring as early as first-episode schizophrenia have been extensively described. Longitudinal studies have demonstrated that these changes may be progressive and associated with clinical outcome. This raises the possibility that antipsychotics might alter such pathomorphologic progression in early-stage schizophrenia. Objective: To test a priori hypotheses that olanzapine-treated patients have less change over time in whole brain gray matter volumes and lateral ventricle volumes than haloperidol-treated patients and that gray matter and lateral ventricle volume changes are associated with changes in psychopathology and neurocognition. Design: Longitudinal, randomized, controlled, multisite, double-blind study. Patients treated and followed up for up to 104 weeks. Neurocognitive and magnetic resonance imaging (MRI) assessments performed at weeks 0 (baseline), 12, 24, 52, and 104. Mixed-models analyses with time-dependent covariates evaluated treatment effects on MRI end points and explored relationships between MRI, psychopathologic, and neurocognitive outcomes. Setting: Fourteen academic medical centers (United States, 11; Canada, 1; Netherlands, 1; England, 1). Participants: Patients with first-episode psychosis (DSM-IV) and healthy volunteers. Interventions: Random allocation to a conventional antipsychotic, haloperidol (2-20 mg/d), or an atypical antipsychotic, olanzapine (5-20 mg/d). Main Outcome Measures: Brain volume changes assessed by MRI. Results: Of 263 randomized patients, 161 had baseline and at least 1 postbaseline MRI evaluation. Haloperidol-treated patients exhibited significant decreases in gray matter volume, whereas olanzapine-treated patients did not. A matched sample of healthy volunteers (n=58) examined contemporaneously showed no change in gray matter volume. Conclusions: Patients with first-episode psychosis exhibited a significant between-treatment difference in MRI volume changes. Haloperidol was associated with significant reductions in gray matter volume, whereas olanzapine was not. Post hoc analyses suggested that treatment effects on brain volume and psychopathology of schizophrenia may be associated. The differential treatment effects on brain morphology could be due to haloperidol-associated toxicity or greater therapeutic effects of olanzapine.

Authors
Lieberman, JA; Tollefson, GD; Charles, C; Zipursky, R; Sharma, T; Kahn, RS; Keefe, RSE; Green, AI; Gur, RE; McEvoy, J; Perkins, D; Hamer, RM; Gu, H; Tohen, M
MLA Citation
Lieberman, JA, Tollefson, GD, Charles, C, Zipursky, R, Sharma, T, Kahn, RS, Keefe, RSE, Green, AI, Gur, RE, McEvoy, J, Perkins, D, Hamer, RM, Gu, H, and Tohen, M. "Antipsychotic drug effects on brain morphology in first-episode psychosis." Archives of General Psychiatry 62.4 (2005): 361-370.
PMID
15809403
Source
scival
Published In
Archives of General Psychiatry
Volume
62
Issue
4
Publish Date
2005
Start Page
361
End Page
370
DOI
10.1001/archpsyc.62.4.361

Impact of APOE in mild cognitive impairment.

OBJECTIVE: The authors aimed to use baseline data of an ongoing large, prospective study in subjects with mild cognitive impairment (MCI) to investigate the impact of APOE genotype on the symptom profile of the condition. METHODS: Cognitive assessments included the AD Assessment Scale cognitive subscale (ADAS-cog), the Mini-Mental State Examination (MMSE), and a cognitive battery for assessment of memory, attention, and executive function. Behavioral assessments included the Neuropsychiatric Inventory and Beck Depression Inventory. Activities of daily living were assessed by the AD Cooperative Study Activities of Daily Living (ADCS-ADL) scale. Hippocampal volumes were measured with MRI. RESULTS: A total of 494 of 1,018 study subjects provided APOE data. Approximately 40% of the subjects were APOE epsilon4 carriers. APOE epsilon4 carriers had lower MMSE (p = 0.01) and higher ADAS-cog (p < 0.0001) scores than noncarriers, indicating worse cognitive impairment. APOE epsilon4 carriers also had greater deficits on New York University delayed paragraph recall and Buschke free and cued selective reminding tests, and on the ADCS-ADL scale (p < 0.001). They also had smaller hippocampal volumes (p = 0.002). Behavioral scores were similar across the subgroups. CONCLUSION: MCI subjects carrying the APOE epsilon4 allele showed distinct cognitive and imaging profiles, which appeared to resemble those of early Alzheimer patients. APOE epsilon4 genotype was associated with greater impairments in memory and functional activities as well as hippocampal atrophy.

Authors
Farlow, MR; He, Y; Tekin, S; Xu, J; Lane, R; Charles, HC
MLA Citation
Farlow, MR, He, Y, Tekin, S, Xu, J, Lane, R, and Charles, HC. "Impact of APOE in mild cognitive impairment." Neurology 63.10 (November 23, 2004): 1898-1901.
PMID
15557508
Source
pubmed
Published In
Neurology
Volume
63
Issue
10
Publish Date
2004
Start Page
1898
End Page
1901

Methodological standardization for a multi-institutional in vivo trial of localized 31P MR spectroscopy in human cancer research. In vitro and normal volunteer studies.

A multi-institutional group has been created to demonstrate the utility of in vivo 31P magnetic resonance spectroscopy (31P-MRS) to study human cancers in vivo. This review is concerned with the novel problems concerning quality control in this large multinational trial of 31P MRS. Our results show that the careful and systematic performance of the quality control tests depicted here (standardized dual 1H/31P tuned radiofrequency probe, quality control procedures, routine use of 1H irradiation while acquiring 31P MR signals) has ensured comparable results between the different institutions. In studies made in vitro, the root-mean-square error was 3.6 %, and in muscle of healthy volunteers in vivo the coefficients of variance for the ratios phosphocreatine/nucleotide-triphosphates, phosphocreatine/noise and nucleotide-triphosphate/noise were 12.2, 7.0 and 10.8 %, respectively. The standardization of the acquisition protocol for in vivo-localized 31P MR spectroscopy across the different institutions has resulted in comparable in vivo data, decreasing the possible problems related to a research study carried out under a multi-institutional setting.

Authors
Arias-Mendoza, F; Zakian, K; Schwartz, A; Howe, FA; Koutcher, JA; Leach, MO; Griffiths, JR; Heerschap, A; Glickson, JD; Nelson, SJ; Evelhoch, JL; Charles, HC; Brown, TR; Cooperative Group on MRS Applications in Cancer,
MLA Citation
Arias-Mendoza, F, Zakian, K, Schwartz, A, Howe, FA, Koutcher, JA, Leach, MO, Griffiths, JR, Heerschap, A, Glickson, JD, Nelson, SJ, Evelhoch, JL, Charles, HC, Brown, TR, and Cooperative Group on MRS Applications in Cancer, . "Methodological standardization for a multi-institutional in vivo trial of localized 31P MR spectroscopy in human cancer research. In vitro and normal volunteer studies." NMR Biomed 17.6 (October 2004): 382-391. (Review)
PMID
15386624
Source
pubmed
Published In
Nmr in Biomedicine
Volume
17
Issue
6
Publish Date
2004
Start Page
382
End Page
391
DOI
10.1002/nbm.915

Neuroimaging: Strategies to illuminate environment-disease linkages: Session II. Summary and research needs

Authors
Jr, WS; Pogge, A; Walker, R; Chatziiannou, A; Charles, C; Ellisman, M
MLA Citation
Jr, WS, Pogge, A, Walker, R, Chatziiannou, A, Charles, C, and Ellisman, M. "Neuroimaging: Strategies to illuminate environment-disease linkages: Session II. Summary and research needs." NeuroToxicology 25.4 SPEC. ISS. (2004): 501-502.
PMID
15183002
Source
scival
Published In
NeuroToxicology
Volume
25
Issue
4 SPEC. ISS.
Publish Date
2004
Start Page
501
End Page
502
DOI
10.1016/j.neuro.2003.09.011

Improved precision of quantitative cartilage measurements with magnetic resonance imaging at 3 T

Authors
Eckstein, F; Buck, RJ; Charles, HC; Hudelmaier, M; Wirth, W; Kraus, VB; Evelhoch, JL
MLA Citation
Eckstein, F, Buck, RJ, Charles, HC, Hudelmaier, M, Wirth, W, Kraus, VB, and Evelhoch, JL. "Improved precision of quantitative cartilage measurements with magnetic resonance imaging at 3 T." 2004.
Source
wos-lite
Published In
Osteoarthritis and Cartilage
Volume
12
Publish Date
2004
Start Page
S119
End Page
S119

Randomized, placebo-controlled trial of the effects of donepezil on neuronal markers and hippocampal volumes in Alzheimer's disease.

OBJECTIVE: The authors examined the effect of the acetylcholinesterase inhibitor donepezil on magnetic resonance markers of neurodegeneration in Alzheimer's disease. METHOD: In this randomized, double-blind, placebo-controlled pilot study, 67 patients with mild to moderate Alzheimer's disease received 24 weeks of treatment with donepezil (5 mg/day for the first 28 days and 10 mg/day thereafter) or placebo. Patients were reevaluated at 6-week intervals to measure change from baseline in several outcome measures, including right, left, and total hippocampal volumes, measured with magnetic resonance imaging; brain concentrations of N-acetylaspartate, measured with proton magnetic resonance spectroscopy; and cognition, assessed with the Alzheimer's Disease Assessment Scale cognitive subscale. RESULTS: At some interim assessments, mean normalized measures of N-acetylaspartate concentration tended to be higher in the donepezil-treated patients than in the patients who received placebo, but these differences were not significant at endpoint. At endpoint, the donepezil-treated patients had significantly smaller mean decreases in total and right hippocampal volumes and a smaller, nearly significant mean decrease in left hippocampal volume, compared with the placebo-treated patients. Mean Alzheimer's Disease Assessment Scale cognitive subscale scores were improved after treatment with donepezil, relative to placebo, at weeks 6, 12, 18, and 24. CONCLUSIONS: These preliminary results suggest that donepezil may have a potentially protective effect in Alzheimer's disease. Larger, longer-term confirmatory studies of the medication's effects are warranted.

Authors
Krishnan, KRR; Charles, HC; Doraiswamy, PM; Mintzer, J; Weisler, R; Yu, X; Perdomo, C; Ieni, JR; Rogers, S
MLA Citation
Krishnan, KRR, Charles, HC, Doraiswamy, PM, Mintzer, J, Weisler, R, Yu, X, Perdomo, C, Ieni, JR, and Rogers, S. "Randomized, placebo-controlled trial of the effects of donepezil on neuronal markers and hippocampal volumes in Alzheimer's disease." Am J Psychiatry 160.11 (November 2003): 2003-2011.
PMID
14594748
Source
pubmed
Published In
American Journal of Psychiatry
Volume
160
Issue
11
Publish Date
2003
Start Page
2003
End Page
2011
DOI
10.1176/appi.ajp.160.11.2003

Focal and lateralized subcortical abnormalities in unipolar major depressive disorder: an automated multivoxel proton magnetic resonance spectroscopy study.

BACKGROUND: The results of prior proton magnetic resonance spectroscopy ((1)H-MRS) studies in unipolar major depressive disorder (MDD) evaluating choline (Cho)/creatine (Cr) and N-acetyl-L-aspartate (NAA)/Cr ratios are mixed. These single-voxel or one-dimensional chemical-shift imaging (CSI) nonautomated (1)H-MRS studies has been unable to evaluate global or lateralized abnormalities in neuronal or membrane function. Using automated multivoxel two-dimensional CSI (1)H-MRS techniques, we tested the hypothesis that patients with MDD have focal neuronal and membrane abnormalities localized in the subcortical region. METHODS: Whole brain and subcortical measures of Cho, NAA, Cr, and myo-inositol (mI) were obtained in 18 patients with MDD and 20 control subjects using automated two-dimensional CSI (1)H-MRS. RESULTS: Compared with control subjects, MDD patients had a significantly lower mean NAA/Cr amplitude in the caudate and a significantly higher mean Cho/Cr amplitude in the putamen, particularly on the right side. No differences were observed for global whole brain measurements. CONCLUSIONS: The findings support reduced neuronal viability or function in the caudate and altered membrane phospholipid metabolism in the putamen for patients with MDD. Our results are consistent with prior magnetic resonance imaging, positron emission tomography, and postmortem reports of focal and lateralized abnormalities of the basal ganglia in MDD.

Authors
Vythilingam, M; Charles, HC; Tupler, LA; Blitchington, T; Kelly, L; Krishnan, KRR
MLA Citation
Vythilingam, M, Charles, HC, Tupler, LA, Blitchington, T, Kelly, L, and Krishnan, KRR. "Focal and lateralized subcortical abnormalities in unipolar major depressive disorder: an automated multivoxel proton magnetic resonance spectroscopy study." Biol Psychiatry 54.7 (October 1, 2003): 744-750.
PMID
14512215
Source
pubmed
Published In
Biological Psychiatry
Volume
54
Issue
7
Publish Date
2003
Start Page
744
End Page
750

Olanzapine induced reductions in frontal lobe lactate levels correlate with treatment response in first episode psychosis

Authors
Renshaw, PF; Yurgelun-Todd, DA; Wei, H; Charles, HC; Tohen, M; Sharma, T; Zipursky, RB; Kahn, R; Gur, RE; Green, AL; McEvoy, JP; Perkins, DO; Hamer, RM; Nemeroff, CB; Rothschild, AJ; Kuldau, JM; Strakowski, SM; Tollefson, GD; Lieberman, JA
MLA Citation
Renshaw, PF, Yurgelun-Todd, DA, Wei, H, Charles, HC, Tohen, M, Sharma, T, Zipursky, RB, Kahn, R, Gur, RE, Green, AL, McEvoy, JP, Perkins, DO, Hamer, RM, Nemeroff, CB, Rothschild, AJ, Kuldau, JM, Strakowski, SM, Tollefson, GD, and Lieberman, JA. "Olanzapine induced reductions in frontal lobe lactate levels correlate with treatment response in first episode psychosis." April 15, 2003.
Source
wos-lite
Published In
Biological Psychiatry
Volume
53
Issue
8
Publish Date
2003
Start Page
67S
End Page
67S

Antipsychotic treatment effects on progression of brain pathomorphology in first episode schizophrenia

Authors
Lieberman, JA; Charles, HC; Sharma, T; Zipursky, RB; Kahn, R; Gur, RE; Tohen, M; Green, AI; McEvoy, JP; Perkins, DO; Hamer, RM; Nemeroff, CB; Rothschild, AJ; Kuldau, JM; Strakowski, SM; Tollefson, GD
MLA Citation
Lieberman, JA, Charles, HC, Sharma, T, Zipursky, RB, Kahn, R, Gur, RE, Tohen, M, Green, AI, McEvoy, JP, Perkins, DO, Hamer, RM, Nemeroff, CB, Rothschild, AJ, Kuldau, JM, Strakowski, SM, and Tollefson, GD. "Antipsychotic treatment effects on progression of brain pathomorphology in first episode schizophrenia." April 15, 2003.
Source
wos-lite
Published In
Biological Psychiatry
Volume
53
Issue
8
Publish Date
2003
Start Page
178S
End Page
178S

Improved attention is associated with reductions in frontal lobe lactate levels in first episode psychosis

Authors
Yurgelun-Todd, DA; Renshaw, PF; Wei, H; Keefe, RSE; Charles, HC; Tohen, M; Seidman, LJ; Christensen, BK; Hamer, RM; Sharma, T; Sitskoorn, MM; Gur, RC; Tollefson, GD; Lieberman, JA
MLA Citation
Yurgelun-Todd, DA, Renshaw, PF, Wei, H, Keefe, RSE, Charles, HC, Tohen, M, Seidman, LJ, Christensen, BK, Hamer, RM, Sharma, T, Sitskoorn, MM, Gur, RC, Tollefson, GD, and Lieberman, JA. "Improved attention is associated with reductions in frontal lobe lactate levels in first episode psychosis." April 15, 2003.
Source
wos-lite
Published In
Biological Psychiatry
Volume
53
Issue
8
Publish Date
2003
Start Page
156S
End Page
156S

Magnetic resonance spectroscopic imaging and its potential application to clinical neurotoxicology

Authors
Charles, HC
MLA Citation
Charles, HC. "Magnetic resonance spectroscopic imaging and its potential application to clinical neurotoxicology." March 2003.
Source
wos-lite
Published In
NeuroToxicology
Volume
24
Issue
2
Publish Date
2003
Start Page
288
End Page
288

MR signal intensity of gray matter/white matter contrast and intracranial fat: effects of age and sex.

Signal intensity (SI) values of gray- and white-matter brain regions of interest (ROIs) were obtained from T(2)- and proton density-weighted magnetic resonance (MR) images of 58 normal subjects aged 22-82 years (31 females, 52.3+/-18.8 years; 27 males, 54.1+/-18.1 years). Sampled ROIs included the caudate, putamen, thalamus, orbitofrontal gyrus, gyrus rectus, uncus, frontal white matter, anterior and posterior corpus callosum, cranial-cervical junction fat, and retroorbital fat. Effects of age and sex on SI were examined using repeated-measures analysis of covariance. For both T(2)- and proton density-weighted acquisitions, a significant inverse relationship between age and SI was observed for the ratio of all summed gray-matter ROIs divided by summed white-matter ROIs. This relationship was additionally observed for ratios of both subcortical gray/white matter and cortical gray/white matter. Females compared with males had significantly lower cortical gray/white matter ratios on T(2)-weighted scans. Differences in SI were observed between cranial-cervical junction fat and retroorbital fat on both acquisitions, with females showing significantly higher values for cranial-cervical junction fat and males showing higher values for retroorbital fat. Implications for brain morphometry, the use of fat as a reference standard, and other issues in neuroimaging are discussed.

Authors
Kim, DM; Xanthakos, SA; Tupler, LA; Barboriak, DP; Charles, HC; MacFall, JR; Krishnan, KRR
MLA Citation
Kim, DM, Xanthakos, SA, Tupler, LA, Barboriak, DP, Charles, HC, MacFall, JR, and Krishnan, KRR. "MR signal intensity of gray matter/white matter contrast and intracranial fat: effects of age and sex." Psychiatry Res 114.3 (July 1, 2002): 149-161.
PMID
12113897
Source
pubmed
Published In
Psychiatry Research
Volume
114
Issue
3
Publish Date
2002
Start Page
149
End Page
161

Learning and recall in subjects at genetic risk for Alzheimer's disease.

Deficits in delayed recall of learned information may be an early marker of Alzheimer's disease (AD). The apolipoprotein E E4 allele and a positive family history (FH) are both genetic risk factors for AD. The authors cross-sectionally compared performance on the California Verbal Learning Test (CVLT) in 153 prospectively recruited normal elderly subjects (mean age 67 years, mean MMSE=28) stratified by genetic risk into four groups (E4+/FH+, E4+/FH-, E4-/FH+, E4-/FH-). Neither FH nor E4 status affected performance, except on List B (a distraction word list), on which the FH+ group performed worse. The high-risk group (E4+/FH+) also performed worse on List B than the low-risk group (E4-/FH-) but did not differ on other measures. Memory impairments associated with genetic or family history risk may not manifest until the person is much closer to the onset age of AD.

Authors
Chen, JG; Edwards, CL; Vidyarthi, S; Pitchumoni, S; Tabrizi, S; Barboriak, D; Charles, HC; Doraiswamy, PM
MLA Citation
Chen, JG, Edwards, CL, Vidyarthi, S, Pitchumoni, S, Tabrizi, S, Barboriak, D, Charles, HC, and Doraiswamy, PM. "Learning and recall in subjects at genetic risk for Alzheimer's disease." J Neuropsychiatry Clin Neurosci 14.1 (2002): 58-63.
PMID
11884656
Source
pubmed
Published In
The Journal of neuropsychiatry and clinical neurosciences
Volume
14
Issue
1
Publish Date
2002
Start Page
58
End Page
63
DOI
10.1176/jnp.14.1.58

Multi-site validation of image analysis methods - Assessing intra and inter-site variability

In this work, we present a unique set of 3D MRI brain data that is appropriate for testing the intra and inter-site variability of image analysis methods. A single subject was scanned two times within a 24 hour time window each at five different MR sites over a period of six weeks using GE and Phillips 1.5 T scanners. The imaging protocol included T1 weighted, Proton Density and T2 weighted images. We applied three quantitative image analysis methods and analyzed their results via the coefficients of variability (COV) and the intra correlation coefficient. The tested methods include two multi-channel tissue segmentation techniques based on an anatomically guided manual seeding and an atlas-based seeding. The third tested method was a single-channel semi-automatic segmentation of the hippocampus. The results show that the outcome of image analysis methods varies significantly for images from different sites and scanners. With the exception of total brain volume, which shows consistent low variability across all images, the COV's were clearly larger between sites than within sites. Also, the COV's between sites with different scanner types are slightly larger than between sites with the same scanner type. The presented existence of a significant inter-site variability requires adaptations in image methods to produce repeatable measurements. This is especially of importance in multi-site clinical research.

Authors
Styner, MA; Charles, HC; Park, J; Gerig, G
MLA Citation
Styner, MA, Charles, HC, Park, J, and Gerig, G. "Multi-site validation of image analysis methods - Assessing intra and inter-site variability." Proceedings of SPIE - The International Society for Optical Engineering 4684 I (2002): 278-286.
Source
scival
Published In
Proceedings of SPIE - The International Society for Optical Engineering
Volume
4684 I
Publish Date
2002
Start Page
278
End Page
286
DOI
10.1117/12.467167

Infant cerebral ventricle volume: a comparison of 3-D ultrasound and magnetic resonance imaging.

Enlargement of the cerebral lateral ventricles is observed in several neuropsychiatric disorders with origins in early brain development. Lateral ventricle size is also predictive of poor neurodevelopmental outcome in premature infants. Three-dimensional (3-D) ultrasound (US) offers an improved methodology for the study of lateral ventricle volume in neonates and infants. To assess the validity of ventricle volume measures obtained with 3-D US, we compared the volumes obtained by 3-D US with magnetic resonance imaging (MRI) in seven infants. Ventricle volumes were determined using a computer-assisted image analysis program, IRIS. There was excellent correlation between ventricle volumes obtained with 3-D US and those obtained with MRI (intraclass correlation coefficient 0.92, F = 23.28, p = 0.00027), indicating that 3-D US provides valid measures of overall lateral ventricle volume compared to the "gold standard" of MRI. 3-D US can provide an economical and practical means of studying lateral ventricle volume in neonates, a neurostructural marker of abnormal brain development.

Authors
Gilmore, JH; Gerig, G; Specter, B; Charles, HC; Wilber, JS; Hertzberg, BS; Kliewer, MA
MLA Citation
Gilmore, JH, Gerig, G, Specter, B, Charles, HC, Wilber, JS, Hertzberg, BS, and Kliewer, MA. "Infant cerebral ventricle volume: a comparison of 3-D ultrasound and magnetic resonance imaging." Ultrasound Med Biol 27.8 (August 2001): 1143-1146.
PMID
11527602
Source
pubmed
Published In
Ultrasound in Medicine & Biology
Volume
27
Issue
8
Publish Date
2001
Start Page
1143
End Page
1146

Outcome in children with fetal mild ventriculomegaly: a case series.

Mild enlargement of the lateral ventricles is associated with schizophrenia and other neurodevelopmental disorders. While it has been hypothesized that ventricle abnormalities associated with neurodevelopmental disorders arise during fetal brain development, there is little direct evidence to support this hypothesis. Using ultrasound, it is possible to image the fetal ventricles in utero. Fetal mild ventriculomegaly (MVM) has been associated with developmental delays in early childhood, though longer-term neurodevelopmental outcome has not been studied. Follow-up of five children (aged 4--9 years) with mild enlargement of the lateral ventricles on prenatal ultrasound and two unaffected co-twins is reported: one child had attention deficit hyperactivity disorder (ADHD), one had autism, and two had evidence of learning disorders. These cases suggest that the mild enlargement of the lateral ventricles associated with these neurodevelopmental disorders arises during fetal brain development and can be detected with prenatal ultrasound. In addition, the presence of mildly enlarged, asymmetric ventricles in two children on prenatal ultrasound and on follow-up MRI at age 6 years indicates that ventricle structure present in utero can persist well into childhood brain development. The study of fetal ventricle development with ultrasound may provide important insights into neurodevelopmental disorders and allow the identification of children at high risk.

Authors
Gilmore, JH; van Tol, JJ; Lewis Streicher, H; Williamson, K; Cohen, SB; Greenwood, RS; Charles, HC; Kliewer, MA; Whitt, JK; Silva, SG; Hertzberg, BS; Chescheir, NC
MLA Citation
Gilmore, JH, van Tol, JJ, Lewis Streicher, H, Williamson, K, Cohen, SB, Greenwood, RS, Charles, HC, Kliewer, MA, Whitt, JK, Silva, SG, Hertzberg, BS, and Chescheir, NC. "Outcome in children with fetal mild ventriculomegaly: a case series." Schizophr Res 48.2-3 (March 30, 2001): 219-226.
PMID
11295375
Source
pubmed
Published In
Schizophrenia Research
Volume
48
Issue
2-3
Publish Date
2001
Start Page
219
End Page
226

Brain 1H-MR spectroscopy in subjects at risk for Alzheimer's disease

Authors
Doraiswamy, PM; Barboriak, D; Krishnan, KRR; Chen, G; Smith, J; Charles, HC
MLA Citation
Doraiswamy, PM, Barboriak, D, Krishnan, KRR, Chen, G, Smith, J, and Charles, HC. "Brain 1H-MR spectroscopy in subjects at risk for Alzheimer's disease." NEUROBIOLOGY OF AGING 22.2 (2001): 336-337.
Source
wos-lite
Published In
Neurobiology of Aging
Volume
22
Issue
2
Publish Date
2001
Start Page
336
End Page
337

Hippocampal sulcal cavities on MRI: relationship to age and apolipoprotein E genotype.

Hippocampal sulcal cavities are usually considered incidental findings on brain MRI. In a group of 92 elderly volunteers, the authors graded the number and size of hippocampal sulcal cavities with brain MRI to obtain a cavity score. Cavity scores increased with age, and were higher in subjects carrying the APOE epsilon4 or epsilon2 alleles than in subjects with the epsilon3/3 genotype. Age-related morphologic changes in the hippocampus may be mediated by the APOE genotype.

Authors
Barboriak, DP; Doraiswamy, PM; Krishnan, KR; Vidyarthi, S; Sylvester, J; Charles, HC
MLA Citation
Barboriak, DP, Doraiswamy, PM, Krishnan, KR, Vidyarthi, S, Sylvester, J, and Charles, HC. "Hippocampal sulcal cavities on MRI: relationship to age and apolipoprotein E genotype." Neurology 54.11 (June 13, 2000): 2150-2153.
PMID
10851380
Source
pubmed
Published In
Neurology
Volume
54
Issue
11
Publish Date
2000
Start Page
2150
End Page
2153

The relationship between intracellular and extracellular pH in spontaneous canine tumors.

Recently, it has been suggested that the cellular uptake of chemotherapeutic drugs may be dependent on the pH gradient between the intracellular (pHi) and extracellular (pHe) compartments. It has been demonstrated in murine tumor models that the extracellular environment is acidic, relative to the intracellular environment, thus favoring preferential accumulation of drugs that are weak acids into cells. However, concomitant measurements of pHi and pHe in spontaneous tumors have not been reported, so it is not certain how well the murine results translate to the clinical scenario. In this study, both types of measurements were performed in dogs with spontaneous malignant soft tissue tumors. On average, pHe was more acidic than pHi, with maintenance of a more physiologically balanced intracellular tumor environment. However, the magnitude of the gradient varied widely, and individual tumors had both positive and negative pH gradients (pHi - pHe). These data suggest that the magnitude and direction of the pH gradient may need to be measured for individual patient tumors and/or that manipulation of pHe may be required if exploitation of the pH gradient is to be achieved for tumor-selective augmentation of intracellular drug delivery.

Authors
Prescott, DM; Charles, HC; Poulson, JM; Page, RL; Thrall, DE; Vujaskovic, Z; Dewhirst, MW
MLA Citation
Prescott, DM, Charles, HC, Poulson, JM, Page, RL, Thrall, DE, Vujaskovic, Z, and Dewhirst, MW. "The relationship between intracellular and extracellular pH in spontaneous canine tumors." Clin Cancer Res 6.6 (June 2000): 2501-2505.
PMID
10873105
Source
pubmed
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
6
Issue
6
Publish Date
2000
Start Page
2501
End Page
2505

Temperature-dependent changes in physiologic parameters of spontaneous canine soft tissue sarcomas after combined radiotherapy and hyperthermia treatment.

PURPOSE: The objectives of this study were to evaluate effects of hyperthermia on tumor oxygenation, extracellular pH (pHe), and blood flow in 13 dogs with spontaneous soft tissue sarcomas prior to and after local hyperthermia. METHODS AND MATERIALS: Tumor pO2 was measured using an Eppendorf polarographic device, pHe using interstitial electrodes, and blood flow using contrast-enhanced magnetic resonance imaging (MRI). RESULTS: There was an overall improvement in tumor oxygenation observed as an increase in median pO2 and decrease in hypoxic fraction (% of pO2 measurements <5 mm Hg) at 24-h post hyperthermia. These changes were most pronounced when the median temperature (T50) during hyperthermia treatment was less than 44 degrees C. Tumors with T50 > 44 degrees C were characterized by a decrease in median PO2 and an increase in hypoxic fraction. Similar thermal dose-related changes were observed in tumor perfusion. Perfusion was significantly higher after hyperthermia. Increases in perfusion were most evident in tumors with T50 < 44 degrees C. With T50 > 44 degrees C, there was no change in perfusion after hyperthermia. On average, pHe values declined in all animals after hyperthermia, with the greatest reduction seen for larger T50 values. CONCLUSION: This study suggests that hyperthermia has biphasic effects on tumor physiologic parameters. Lower temperatures tend to favor improved perfusion and oxygenation, whereas higher temperatures are more likely to cause vascular damage, thus leading to greater hypoxia. While it has long been recognized that such effects occur in rodent tumors, this is the first report to tie such changes to temperatures achieved during hyperthermia in the clinical setting. Furthermore, it suggests that the thermal threshold for vascular damage is higher in spontaneous tumors than in more rapidly growing rodent tumors.

Authors
Vujaskovic, Z; Poulson, JM; Gaskin, AA; Thrall, DE; Page, RL; Charles, HC; MacFall, JR; Brizel, DM; Meyer, RE; Prescott, DM; Samulski, TV; Dewhirst, MW
MLA Citation
Vujaskovic, Z, Poulson, JM, Gaskin, AA, Thrall, DE, Page, RL, Charles, HC, MacFall, JR, Brizel, DM, Meyer, RE, Prescott, DM, Samulski, TV, and Dewhirst, MW. "Temperature-dependent changes in physiologic parameters of spontaneous canine soft tissue sarcomas after combined radiotherapy and hyperthermia treatment." Int J Radiat Oncol Biol Phys 46.1 (January 1, 2000): 179-185.
PMID
10656391
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
46
Issue
1
Publish Date
2000
Start Page
179
End Page
185

Magnetic resonance spectroscopy in Alzheimer's disease: focus on N-acetylaspartate.

This paper reviews published post-mortem brain and in-vivo proton magnetic resonance spectroscopy (1H-MRS) studies in Alzheimer's disease (AD) and focuses on the emerging role of N-acetylaspartate (NAA) as a prognostic marker of neuronal function. Post-mortem brain studies have reported significantly lower NAA levels in AD brains than in control brains, and some have correlated the low levels with neuropathological findings (i.e. amyloid plaques and neurofibrillary tangles). Similarly, almost all published in-vivo studies have reported lower NAA levels in AD patients compared to elderly controls. While some studies have found changes in metabolite levels that were considered useful for the diagnosis of AD, most have found that 1H-MRS provided little or no advantages over other, more common diagnostic tools. Instead, recent studies in AD and other neuropsychiatric disorders suggest that NAA may be more useful as a prognostic marker for monitoring neurodegeneration, stabilization, or improvement, and for evaluating therapeutic response to novel drugs.

Authors
Chen, JG; Charles, HC; Barboriak, DP; Doraiswamy, PM
MLA Citation
Chen, JG, Charles, HC, Barboriak, DP, and Doraiswamy, PM. "Magnetic resonance spectroscopy in Alzheimer's disease: focus on N-acetylaspartate." Acta Neurol Scand Suppl 176 (2000): 20-26. (Review)
PMID
11261801
Source
pubmed
Published In
Acta Neurologica Scandinavica, Supplement
Volume
176
Publish Date
2000
Start Page
20
End Page
26

Brain magnetic resonance spectroscopy: Role in assessing outcomes in Alzheimer's disease

Contemporary 1H-magnetic resonance spectroscopy (MRS) techniques can estimate the levels of brain metabolites with a high reproducibility and add only 10 minutes to a routine or volumetric magnetic resonance imaging scan. In patients with Alzheimer's disease (AD), 1H-MRS demonstrates decreases in N-acetylaspartate (NAA) and increases in myo-inositol (Ino) levels. Changes in NAA and Ino levels correlate with dementia severity and may predict future cognitive decline. 1H-MRS could be a valuable outcome measure in clinical trials of individuals with AD for monitoring disease progression (using NAA and Ino levels) and evaluating therapeutic response to novel drugs (using NAA, choline and Ino levels). Further studies are warranted to evaluate the relative utility of 1H-MRS compared with other imaging markers, such as cerebral blood flow and volumetric measures of atrophy. Protocols combining magnetic resonance perfusion, volumetry and spectroscopy in AD may prove to be powerful research tools.

Authors
Doraiswamy, PM; Chen, JG; Charles, HC
MLA Citation
Doraiswamy, PM, Chen, JG, and Charles, HC. "Brain magnetic resonance spectroscopy: Role in assessing outcomes in Alzheimer's disease." CNS Drugs 14.6 (2000): 457-472.
Source
scival
Published In
CNS drugs
Volume
14
Issue
6
Publish Date
2000
Start Page
457
End Page
472

Hyperpolarized 3He-enhanced MR imaging of lung transplant recipients: preliminary results.

OBJECTIVE: Bronchiolitis obliterans syndrome is the major cause of long-term graft failure in lung transplant recipients and may be partially reversible if diagnosed early and treated. Diagnosis is difficult because findings of transbronchial biopsy are often negative in patients with early disease. We are investigating a novel MR ventilation agent, hyperpolarized 3He, for evaluating ventilatory abnormalities in lung transplant recipients with suspected bronchiolitis obliterans syndrome. CONCLUSION: In this preliminary study, the extent of ventilatory defects revealed on 3He-enhanced MR images correlated with severity of bronchiolitis obliterans syndrome using an established clinical grading system. This new technique may hold potential for diagnosing bronchiolitis obliterans syndrome in lung transplant recipients.

Authors
McAdams, HP; Palmer, SM; Donnelly, LF; Charles, HC; Tapson, VF; MacFall, JR
MLA Citation
McAdams, HP, Palmer, SM, Donnelly, LF, Charles, HC, Tapson, VF, and MacFall, JR. "Hyperpolarized 3He-enhanced MR imaging of lung transplant recipients: preliminary results." AJR Am J Roentgenol 173.4 (October 1999): 955-959.
PMID
10511156
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
173
Issue
4
Publish Date
1999
Start Page
955
End Page
959
DOI
10.2214/ajr.173.4.10511156

Cystic fibrosis: combined hyperpolarized 3He-enhanced and conventional proton MR imaging in the lung--preliminary observations.

Four patients with cystic fibrosis (CF) were examined with combined hyperpolarized helium 3-enhanced and conventional proton magnetic resonance (MR) imaging. After inhalation of the polarized 3He gas, single breath-hold, gradient-echo images (resonant frequency of 3He) were obtained to depict lung ventilation. Conventional T2-weighted fast spin-echo (hydrogen) images were also obtained to depict morphologic abnormalities. 3He images were successfully and reproducibly generated that showed both morphologic abnormalities and, often more extensive, ventilation abnormalities. 3He MR imaging may provide a method for evaluating progression of pulmonary disease in patients with CF.

Authors
Donnelly, LF; MacFall, JR; McAdams, HP; Majure, JM; Smith, J; Frush, DP; Bogonad, P; Charles, HC; Ravin, CE
MLA Citation
Donnelly, LF, MacFall, JR, McAdams, HP, Majure, JM, Smith, J, Frush, DP, Bogonad, P, Charles, HC, and Ravin, CE. "Cystic fibrosis: combined hyperpolarized 3He-enhanced and conventional proton MR imaging in the lung--preliminary observations." Radiology 212.3 (September 1999): 885-889.
PMID
10478261
Source
pubmed
Published In
Radiology
Volume
212
Issue
3
Publish Date
1999
Start Page
885
End Page
889
DOI
10.1148/radiology.212.3.r99se20885

One-methyl group metabolism in non-ketotic hyperglycinaemia: mildly elevated cerebrospinal fluid homocysteine levels.

Non-ketotic hyperglycinaemia (NKH) is a rare, severe brain disease caused by deficient glycine cleavage enzyme complex activity resulting in elevated glycine concentrations. Recent experience suggests that factors in addition to glycine kinetics are involved in its pathogenesis. The glycine cleavage reaction through the formation of methylenetetrahydrofolate is an important one-methyl group donor. A deficiency in one-methyl group metabolites, in particular of choline, has been hypothesized in NKH. We investigated metabolites involved in one-methyl group metabolism in plasma and CSF of 8 patients with NKH, and monitored the effect of treatment with choline in one patient. Plasma and CSF choline and phosphatidylcholine concentrations were normal, except for a low plasma choline in the single neonate studied. Choline treatment did not change brain choline content, and was not associated with clinical or radiological improvement. Methionine concentrations and, in one-patient, S-adenosylmethionine and 5-methyltetrahydrofolate concentrations were normal in CSF. Homocysteine concentrations in CSF, however, were slightly but consistently elevated in all four patients examined, but cysteine, cysteinylglycine and glutathione were normal. Serine is important in the transfer of one-methyl groups from mitochondria to cytosol. Serine concentrations were normal in plasma and CSF, but dropped to below normal in CSF in three patients on benzoate treatment. These observations add to our understanding of the complex metabolic disturbances in NKH.

Authors
Van Hove, JL; Lazeyras, F; Zeisel, SH; Bottiglieri, T; Hyland, K; Charles, HC; Gray, L; Jaeken, J; Kahler, SG
MLA Citation
Van Hove, JL, Lazeyras, F, Zeisel, SH, Bottiglieri, T, Hyland, K, Charles, HC, Gray, L, Jaeken, J, and Kahler, SG. "One-methyl group metabolism in non-ketotic hyperglycinaemia: mildly elevated cerebrospinal fluid homocysteine levels." J Inherit Metab Dis 21.8 (December 1998): 799-811.
PMID
9870205
Source
pubmed
Published In
Journal of Inherited Metabolic Disease
Volume
21
Issue
8
Publish Date
1998
Start Page
799
End Page
811

Prediction of cognitive decline in early Alzheimer's disease.

Authors
Doraiswamy, PM; Charles, HC; Krishnan, KR
MLA Citation
Doraiswamy, PM, Charles, HC, and Krishnan, KR. "Prediction of cognitive decline in early Alzheimer's disease." Lancet 352.9141 (November 21, 1998): 1678-. (Letter)
PMID
9853445
Source
pubmed
Published In
The Lancet
Volume
352
Issue
9141
Publish Date
1998
Start Page
1678
DOI
10.1016/S0140-6736(05)61449-3

Metabolic brain mapping in Alzheimer's disease using proton magnetic resonance spectroscopy.

Alzheimer's disease (AD) is a progressive disorder associated with disruption of neuronal function and neuronal loss. N-acetylaspartate (NAA) is a marker of neuronal content and can be assessed using proton (1H) magnetic resonance spectroscopy (MRS). We utilized 1H-MRS (two-dimensional chemical-shift imaging) to assess amplitudes and areas of NAA, as well as choline moieties (Cho), creatine (Cr) and myo-inositol (mI), in 15 AD patients compared with 14 control subjects. Voxels were classified as predominantly cortical gray matter (CGM), subcortical gray matter (SGM), or white matter (WM). Compared with control subjects, AD patients exhibited decreased NAA/Cho and NAA/Cr amplitudes, whereas an increase was observed in Cho/Cr and in amplitude ratios involving mI. Area ratios were significant in the same direction for NAA/Cho, NAA/Cr, mI/Cr and mI/NAA. No significant effects of tissue type were observed; however, significant group x tissue type interactions were noted for Cho/Cr and mI/Cr amplitudes. Our study confirms that 1H-MRS can identify distinct physicochemical alterations in AD patients, reflecting membrane changes and diminished neuronal function. These alterations can be used as longitudinal markers for the disease.

Authors
Lazeyras, F; Charles, HC; Tupler, LA; Erickson, R; Boyko, OB; Krishnan, KR
MLA Citation
Lazeyras, F, Charles, HC, Tupler, LA, Erickson, R, Boyko, OB, and Krishnan, KR. "Metabolic brain mapping in Alzheimer's disease using proton magnetic resonance spectroscopy." Psychiatry Res 82.2 (May 20, 1998): 95-106.
PMID
9754452
Source
pubmed
Published In
Psychiatry Research
Volume
82
Issue
2
Publish Date
1998
Start Page
95
End Page
106

Magnetic resonance thermometry during hyperthermia for human high-grade sarcoma.

PURPOSE: To determine the feasibility of measuring temperature noninvasively with magnetic resonance imaging during hyperthermia treatment of human tumors. METHODS: The proton chemical shift detected using phase-difference magnetic resonance imaging (MRI) was used to measure temperature in phantoms and human tumors during treatment with hyperthermia. Four adult patients having high-grade primary sarcoma tumors of the lower leg received 5 hyperthermia treatments in the MR scanner using an MRI-compatible radiofrequency heating applicator. Prior to each treatment, an average of 3 fiberoptic temperature probes were invasively placed into the tumor (or phantom). Hyperthermia was applied concurrent with MR thermometry. Following completion of the treatment, regions of interest (ROI) were defined on MR phase images at each temperature probe location, in bone marrow, and in gel standards placed outside the heated region. The median phase difference (compared to pretreatment baseline images) was calculated for each ROI. This phase difference was corrected for phase drift observed in standards and bone marrow. The observed phase difference, with and without corrections, was correlated with the fiberoptic temperature measurements. RESULTS: The phase difference observed with MRI was found to correlate with temperature. Phantom measurements demonstrated a linear regression coefficient of 4.70 degrees phase difference per degree Celsius, with an R2 = 0.998. After human images with artifact were excluded, the linear regression demonstrated a correlation coefficient of 5.5 degrees phase difference per degree Celsius, with an R2 = 0.84. In both phantom and human treatments, temperature measured via corrected phase difference closely tracked measurements obtained with fiberoptic probes during the hyperthermia treatments. CONCLUSIONS: Proton chemical shift imaging with current MRI and hyperthermia technology can be used to monitor and control temperature during treatment of large tumors in the distal lower extremity.

Authors
Carter, DL; MacFall, JR; Clegg, ST; Wan, X; Prescott, DM; Charles, HC; Samulski, TV
MLA Citation
Carter, DL, MacFall, JR, Clegg, ST, Wan, X, Prescott, DM, Charles, HC, and Samulski, TV. "Magnetic resonance thermometry during hyperthermia for human high-grade sarcoma." Int J Radiat Oncol Biol Phys 40.4 (March 1, 1998): 815-822.
PMID
9531365
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
40
Issue
4
Publish Date
1998
Start Page
815
End Page
822

Clinical applications of neuroimaging in psychiatry

New techniques are dramatically expanding current clinical applications of neuroimaging in neuropsychiatry. Neuroimaging research that examines brain structure and function relationships in neuropsychiatric disorders is also enhancing our understanding of the pathopyshiology of neuropsychiatric illness such as dementia, focal CNS insult, schizophrenia, affective disorders, and neurodevelopmental disorders.

Authors
Chakos, MH; Esposito, S; Charles, C; Lieberman, JA
MLA Citation
Chakos, MH, Esposito, S, Charles, C, and Lieberman, JA. "Clinical applications of neuroimaging in psychiatry." Magnetic Resonance Imaging Clinics of North America 6.1 (1998): 155-164.
PMID
9449746
Source
scival
Published In
Magnetic Resonance Imaging Clinics of North America
Volume
6
Issue
1
Publish Date
1998
Start Page
155
End Page
164

Hyperthermic treatment of malignant diseases: current status and a view toward the future.

New studies in hyperthermia at the basic science, engineering, and clinical level have stimulated renewed enthusiasm for re-investigating its potential as an anticancer therapy. This article reviews the salient features of these recent results and points out areas for additional investigation. Highlighting these new results is the publication of several positive phase III trials for thermoradiotherapy compared to radiotherapy alone. Important highlights are the encouraging results using magnetic resonance imaging for noninvasive thermometry. If this technology is successfully implemented with real time power control it will revolutionize the clinical application of hyperthermia.

Authors
Dewhirst, MW; Prosnitz, L; Thrall, D; Prescott, D; Clegg, S; Charles, C; MacFall, J; Rosner, G; Samulski, T; Gillette, E; LaRue, S
MLA Citation
Dewhirst, MW, Prosnitz, L, Thrall, D, Prescott, D, Clegg, S, Charles, C, MacFall, J, Rosner, G, Samulski, T, Gillette, E, and LaRue, S. "Hyperthermic treatment of malignant diseases: current status and a view toward the future." Semin Oncol 24.6 (December 1997): 616-625. (Review)
PMID
9422258
Source
pubmed
Published In
Seminars in Oncology
Volume
24
Issue
6
Publish Date
1997
Start Page
616
End Page
625

Normal skeletal muscle contractile function in patients with chronic heart failure

Authors
Rosenberg, BS; Green, H; Schachat, F; Charles, HC; Adams, KF; Hawthorne, MH; Duscha, BD; Sloniger, M; Sullivan, MJ
MLA Citation
Rosenberg, BS, Green, H, Schachat, F, Charles, HC, Adams, KF, Hawthorne, MH, Duscha, BD, Sloniger, M, and Sullivan, MJ. "Normal skeletal muscle contractile function in patients with chronic heart failure." CIRCULATION 96.8 (October 21, 1997): 1785-1785.
Source
wos-lite
Published In
Circulation
Volume
96
Issue
8
Publish Date
1997
Start Page
1785
End Page
1785

A repeat proton magnetic resonance spectroscopy study in social phobia.

Peak spectral amplitudes for choline moieties (Cho), creatine (Cr), N-acetylaspartate (NAA), and myo-inositol (mI) were examined using proton magnetic resonance spectroscopy in 19 social-phobia patients and 10 controls. Compared with controls, social phobics demonstrated significantly lower NAA/Cho and higher Cho/Cr, mI/Cr, and mI/NAA amplitudes in cortical gray matter. Higher mI/Cr and mI/NAA amplitudes for social phobics were also observed in subcortical gray matter. Minimal between-group differences were noted for white matter. Symptom severity correlated inversely with amplitudes primarily in subcortical gray matter, and to a lesser extent in cortical gray matter. Inclusion of age and sex in statistical modeling strengthened comparisons with controls but eliminated those for symptom severity. No changes were observed in any amplitude measure following at least 8 weeks of clonazepam treatment, nor was a relationship observed between amplitudes and cumulative clonazepam dose. The possible psychobiological implications of our findings in social phobia are discussed.

Authors
Tupler, LA; Davidson, JR; Smith, RD; Lazeyras, F; Charles, HC; Krishnan, KR
MLA Citation
Tupler, LA, Davidson, JR, Smith, RD, Lazeyras, F, Charles, HC, and Krishnan, KR. "A repeat proton magnetic resonance spectroscopy study in social phobia." Biol Psychiatry 42.6 (September 15, 1997): 419-424.
PMID
9285077
Source
pubmed
Published In
Biological Psychiatry
Volume
42
Issue
6
Publish Date
1997
Start Page
419
End Page
424
DOI
10.1016/S0006-3223(96)00501-X

Radiation therapy and hyperthermia improve the oxygenation of human soft tissue sarcomas.

The adverse prognostic impact of tumor hypoxia has been demonstrated in human malignancy. We report the effects of radiotherapy and hyperthermia (HT) on soft tissue sarcoma oxygenation and the relationship between treatment-induced changes in oxygenation and clinical treatment outcome. Patients receiving preoperative radiotherapy and HT underwent tumor oxygenation measurement pretreatment after the start of radiation/pre-HT and one day after the first HT treatment. The magnitude of improvement in tumor oxygenation after the first HT fraction relative to pretreatment baseline was positively correlated with the amount of necrosis seen in the resection specimen. Patients with <90% resection specimen necrosis experienced longer disease-free survival than those with > or = 90% necrosis. Increasing levels of tumor hypoxia were also correlated with diminished metabolic status as measured by P-31 magnetic resonance spectroscopy.

Authors
Brizel, DM; Scully, SP; Harrelson, JM; Layfield, LJ; Dodge, RK; Charles, HC; Samulski, TV; Prosnitz, LR; Dewhirst, MW
MLA Citation
Brizel, DM, Scully, SP, Harrelson, JM, Layfield, LJ, Dodge, RK, Charles, HC, Samulski, TV, Prosnitz, LR, and Dewhirst, MW. "Radiation therapy and hyperthermia improve the oxygenation of human soft tissue sarcomas." Cancer Res 56.23 (December 1, 1996): 5347-5350.
PMID
8968082
Source
pubmed
Published In
Cancer Research
Volume
56
Issue
23
Publish Date
1996
Start Page
5347
End Page
5350

Proton-decoupled phosphorus-31 magnetic resonance spectroscopy in the evaluation of native and well-functioning transplanted kidneys.

RATIONALE AND OBJECTIVES: To evaluate whether decoupling improves signal-to-noise ratio and frequency resolution of in vivo kidney spectra, and to compare native and well-functioning transplant kidneys. METHODS: Proton decoupling in conjunction with three-dimensional chemical shift imaging (3D-CSI) in phosphorus-31 magnetic resonance (MR) spectroscopy was used with a spatial resolution of 64 cm3 and 17-minute acquisition time to compare native (n = 10) and well-functioning transplant (n = 9) kidneys. RESULTS: Proton decoupling improved peak amplitudes by almost 30%, as well as chemical shift resolution of in vivo kidney spectra. No statistically significant differences in phosphometabolite ratios and renal spectra were observed between healthy volunteers and patients with nonrejecting transplants. The phosphodiester-phosphomonoester ratio was 3.02 +/- 0.88, phosphomonoester-inorganic phosphate ratio was 1.07 +/- 0.44, and inorganic phosphate-adenosine triphosphate ratio was 0.58 +/- 0.22 after correction for saturation effects. CONCLUSION: Improved spectra of native and transplant kidneys can be obtained in vivo with MR spectroscopy by using a short acquisition time.

Authors
Vallée, JP; Lazeyras, F; Sostman, HD; Smith, SR; Butterly, DW; Spritzer, CE; Charles, HC
MLA Citation
Vallée, JP, Lazeyras, F, Sostman, HD, Smith, SR, Butterly, DW, Spritzer, CE, and Charles, HC. "Proton-decoupled phosphorus-31 magnetic resonance spectroscopy in the evaluation of native and well-functioning transplanted kidneys." Acad Radiol 3.12 (December 1996): 1030-1037.
PMID
9017019
Source
pubmed
Published In
Academic Radiology
Volume
3
Issue
12
Publish Date
1996
Start Page
1030
End Page
1037

Accuracy and reproducibility of brain and tissue volumes using a magnetic resonance segmentation method.

Magnetic resonance (MR) imaging now allows the qualitative and quantitative assessment of the human brain in vivo. As MR imaging resolution has improved, precise measurement of small brain structures has become possible. Methods of measuring brain regions from MR images include both manual and semiautomated methods. Despite the development of numerous volumetric methods, there have been only limited attempts so far to evaluate the accuracy and reproducibility of these methods. In this study we used phantoms to assess the accuracy of the segmentation process. Our results with simple and complex phantoms indicate an error of 3-5% using either manual or semiautomated techniques. We subsequently used manual and semiautomated volumetric methodologies to study human brain structures in vivo in five normal subjects. Supervised segmentation is a semiautomated method that accomplishes the division of MR images into several tissue types based on differences in signal intensity. This technique requires the operator to manually identify points on the MR images that characterize each tissue type, a process known as seeding. However, the use of supervised segmentation to assess the volumes of gray and white matter is subject to pitfalls. Inhomogeneities of the radiofrequency or magnetic fields can result in misclassification of tissue points during the tissue seeding process, limiting the accuracy and reliability of the segmentation process. We used a structured seeding protocol that allowed for field inhomogeneity that produced reduced variation in measured tissue volumes. We used repeated segmentations to assess intra- and inter-rater reliability, and were able to measure small and large regions of interest with a small degree of variation. In addition, we demonstrated that measurements are reproducible with repeat MR acquisitions, with minimal interscan variability. Segmentation methods can accurately and reliably measure subtle morphometric changes, and will prove a boon to the study of neuropsychiatric disorders.

Authors
Byrum, CE; MacFall, JR; Charles, HC; Chitilla, VR; Boyko, OB; Upchurch, L; Smith, JS; Rajagopalan, P; Passe, T; Kim, D; Xanthakos, S; Ranga, K; Krishnan, R
MLA Citation
Byrum, CE, MacFall, JR, Charles, HC, Chitilla, VR, Boyko, OB, Upchurch, L, Smith, JS, Rajagopalan, P, Passe, T, Kim, D, Xanthakos, S, Ranga, K, and Krishnan, R. "Accuracy and reproducibility of brain and tissue volumes using a magnetic resonance segmentation method." Psychiatry Res 67.3 (October 7, 1996): 215-234.
PMID
8912960
Source
pubmed
Published In
Psychiatry Research
Volume
67
Issue
3
Publish Date
1996
Start Page
215
End Page
234

1H MRI phase thermometry in vivo in canine brain, muscle, and tumor tissue.

The temperature sensitivity of the chemical shift of water (approximately 0.01 ppm/degree C) provides a potential method to monitor temperature changes in vivo or in vitro through the changes in phase of a gradient-echo magnetic resonance (MR) image. This relation was studied at 1.5 T in gel materials and in vivo in canine brain and muscle tissue, heated with a radio frequency (rf) annular phased array hyperthermia antenna. The rf fields associated with heating (130 MHz) and imaging (64 MHz) were decoupled using bandpass filters providing isolation in excess of 100 dB, thus allowing simultaneous imaging and rf heating without deterioration of the MR image signal-to-noise ratio. In a gel, temperature sensitivity of the MR image phase was observed to be (4.41 +/- 0.02) phase degrees/degree C for Te = 20 ms, which allowed temperature changes of 0.22 degree C to be resolved for a 50-mm3 region in less than 10 s of data acquisition. In vivo, for Te = 20 ms, the temperature sensitivity was (3.2 +/- 0.1) phase degrees/degree C for brain tissue, (3.1 +/- 0.1) phase degrees/degree C for muscle, and (3.0 +/- 0.2) phase degrees/degree C for a muscle tumor (sarcoma), allowing temperature changes of 0.6 degree C to be resolved in a 16-mm3 volume in less than 10 s of data acquisition. We conclude that, while the technique is very sensitive to magnetic field inhomogeneity, stability, and subject motion, it appears to be useful for in vivo temperature change measurement.

Authors
MacFall, JR; Prescott, DM; Charles, HC; Samulski, TV
MLA Citation
MacFall, JR, Prescott, DM, Charles, HC, and Samulski, TV. "1H MRI phase thermometry in vivo in canine brain, muscle, and tumor tissue." Med Phys 23.10 (October 1996): 1775-1782.
PMID
8946373
Source
pubmed
Published In
Medical physics
Volume
23
Issue
10
Publish Date
1996
Start Page
1775
End Page
1782
DOI
10.1118/1.597760

Monitoring of neoadjuvant therapy response of soft-tissue and musculoskeletal sarcoma using fluorine-18-FDG PET.

UNLABELLED: The purpose of this study was to investigate the potential role of FDG-PET in the monitoring of neoadjuvant therapy of soft-tissue and musculoskeletal sarcomas. METHODS: Nine patients were studied. Neoadjuvant therapy consisted of either chemotherapy or combined radiotherapy and hyperthermia. The FDG-PET studies were obtained, when possible, prior to therapy, 1-3 wk after commencement of therapy, and prior to surgery after completion of neoadjuvant therapy. In two patients, all three studies were completed. The remainder of patients underwent one or two studies at varying timepoints. RESULTS: In tumors treated with combined radiotherapy and hyperthermia, well-defined regions of absent uptake developed within responsive tumors, correlating pathologically with necrosis. Following treatment, a peripheral rim of FDG accumulation was found to correlate pathologically with the formation of a fibrous pseudocapsule. In tumors treated with chemotherapy, FDG accumulation decreased more homogeneously throughout the tumor, in responsive cases. Despite 100% tumor cell kill in some patients, persistent tumor FDG uptake was observed which correlated pathologically with uptake within benign therapy-related fibrous tissue. Significant FDG accumulation was also observed at the site of an uncontaminated incisional biopsy. CONCLUSION: These initial results demonstrate changes in tumor accumulation of FDG during and after neoadjuvant therapy; these changes are dependent on the type of neoadjuvant therapy administered. Prominent FDG accumulation was observed in benign tissues both within and adjacent to the treated tumor.

Authors
Jones, DN; McCowage, GB; Sostman, HD; Brizel, DM; Layfield, L; Charles, HC; Dewhirst, MW; Prescott, DM; Friedman, HS; Harrelson, JM; Scully, SP; Coleman, RE
MLA Citation
Jones, DN, McCowage, GB, Sostman, HD, Brizel, DM, Layfield, L, Charles, HC, Dewhirst, MW, Prescott, DM, Friedman, HS, Harrelson, JM, Scully, SP, and Coleman, RE. "Monitoring of neoadjuvant therapy response of soft-tissue and musculoskeletal sarcoma using fluorine-18-FDG PET." J Nucl Med 37.9 (September 1996): 1438-1444.
PMID
8790188
Source
pubmed
Published In
Journal of nuclear medicine : official publication, Society of Nuclear Medicine
Volume
37
Issue
9
Publish Date
1996
Start Page
1438
End Page
1444

Human lung air spaces: potential for MR imaging with hyperpolarized He-3.

Two healthy volunteers who had inhaled approximately 0.75 L of laser-polarized helium-3 gas underwent magnetic resonance imaging at 1.5 T with fast gradient-echo pulse sequences and small flip angles ( < 10 degrees). Thick-section (20 mm) coronal images, time-course data (30 images collected every 1.8 seconds), and thin-section (6 mm) images were acquired. Subjects were able to breathe the gas (12% polarization) without difficulty. Thick-section images were of good quality and had a signal-to-noise ratio (S/N) of 32:1 near the surface coil and 16:1 farther away. The time images showed regional differences, which indicated potential value for quantitation. High-resolution images showed greater detail and a S/N of approximately 6:1.

Authors
MacFall, JR; Charles, HC; Black, RD; Middleton, H; Swartz, JC; Saam, B; Driehuys, B; Erickson, C; Happer, W; Cates, GD; Johnson, GA; Ravin, CE
MLA Citation
MacFall, JR, Charles, HC, Black, RD, Middleton, H, Swartz, JC, Saam, B, Driehuys, B, Erickson, C, Happer, W, Cates, GD, Johnson, GA, and Ravin, CE. "Human lung air spaces: potential for MR imaging with hyperpolarized He-3." Radiology 200.2 (August 1996): 553-558.
PMID
8685356
Source
pubmed
Published In
Radiology
Volume
200
Issue
2
Publish Date
1996
Start Page
553
End Page
558
DOI
10.1148/radiology.200.2.8685356

Magnetic resonance imaging of Alzheimer's disease.

1. Although dementia is caused by a heterogeneous group of diseases and pathologic states, Alzheimer's disease is the largest cause, estimated to account for 50 to 75% of all dementias. 2. Unfortunately, confirmation of Alzheimer's disease (AD) requires postmortem histologic confirmation; clinical diagnosis prior to death remains one of exclusion. 3. A large number of structural and volumetric MRI studies have noted anatomic and structural changes accompanying AD, including variable degrees of general cortical atrophy. 4. A classic feature reported by many MRI studies is hippocampal and temporal lobe atrophy. 5. White matter hyperintensities on MRI are common, especially in late onset AD although their significance is still controversial. 6. This article reviews the contribution of magnetic resonance to imaging the neuropathologic changes of AD, discussing both advantages and limitations, and summarizing the major findings.

Authors
Xanthakos, S; Krishnan, KR; Kim, DM; Charles, HC
MLA Citation
Xanthakos, S, Krishnan, KR, Kim, DM, and Charles, HC. "Magnetic resonance imaging of Alzheimer's disease." Prog Neuropsychopharmacol Biol Psychiatry 20.4 (May 1996): 597-626. (Review)
PMID
8843486
Source
pubmed
Published In
Progress in Neuro-Psychopharmacology & Biological Psychiatry
Volume
20
Issue
4
Publish Date
1996
Start Page
597
End Page
626

Reproducibility of high spatial resolution proton magnetic resonance spectroscopic imaging in the human brain.

The application of proton (1H) magnetic resonance spectroscopic imaging (MRSI) allows for noninvasive, localized analyses of brain biochemistry; however, minimal work has been devoted to the evaluation of 1H MRSI reproducibility. This study examined the reproducibility of 1H MRSI from five normal subjects on two occasions, separated by 10 days. Reproducibility of the MR signal was evaluated in the context of automated shimming, automated processing, and accurate subject repositioning. Reliability measures for physicochemical indices (choline moieties, creatine, N-acetylaspartate, and myo-inositol) were moderately concordant across repeat studies. Gain variation and repositioning results were excellent. It has been concluded that 1H MRSI reproducibility is adequate for serial studies of brain metabolism.

Authors
Charles, HC; Lazeyras, F; Tupler, LA; Krishnan, KR
MLA Citation
Charles, HC, Lazeyras, F, Tupler, LA, and Krishnan, KR. "Reproducibility of high spatial resolution proton magnetic resonance spectroscopic imaging in the human brain." Magn Reson Med 35.4 (April 1996): 606-610.
PMID
8992213
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
35
Issue
4
Publish Date
1996
Start Page
606
End Page
610

1H MRI phase thermometry in vivo in canine brain, muscle, and tumor tissue

The temperature sensitivity of the chemical shift of water (approximately 0.01 ppm/°C) provides a potential method to monitor temperature changes in vivo or in vitro through the changes in phase of a gradient-echo magnetic resonance (MR) image. This relation was studied at 1.5 T in gel materials and in vivo in canine brain and muscle tissue, heated with a radio frequency (rf) annular phased array hyperthermia antenna. The rf fields associated with heating (130 MHz) and imaging (64 MHz) were decoupled using bandpass filters providing isolation in excess of 100 dB, thus allowing simultaneous imaging and rf heating without deterioration of the MR image signal-to-noise ratio. In a gel, temperature sensitivity of the MR image phase was observed to be (4.41±0.02) phase degrees/°C for T(e)=20 ms, which allowed temperature changes of 0.22 °C to be resolved for a 50-mm3 region in less than 10 s of data acquisition. In vivo, for T(e)=20 ms, the temperature sensitivity was (3.2 ± 0.1) phase degrees/°C for brain tissue, (3.1 ± 0.1) phase degrees/°C for muscle, and (3.0±0.2) phase degrees/°C for a muscle tumor (sarcoma), allowing temperature changes of 0.6 °C to be resolved in a 16-mm3 volume in less than 10 s of data acquisition. We conclude that, while the technique is very sensitive to magnetic field inhomogeneity, stability, and subject motion, it appears to be useful for in vivo temperature change measurement.

Authors
MacFall, JR; Prescott, DM; Charles, HC; Samulski, TV
MLA Citation
MacFall, JR, Prescott, DM, Charles, HC, and Samulski, TV. "1H MRI phase thermometry in vivo in canine brain, muscle, and tumor tissue." Medical Physics 23.10 (1996): 1775-1782.
Source
scival
Published In
Medical physics
Volume
23
Issue
10
Publish Date
1996
Start Page
1775
End Page
1782
DOI
10.1118/1.597760

Cognitive functioning and brain magnetic resonance imaging in children with sickle cell disease

Objective. Brain magnetic resonance imaging (MRI) and neuropsychological evaluations were conducted to determine whether neuroradiographic evidence of infarct in children with sickle cell disease between ages 6 and 12 years would result in impairment in cognitive and academic functioning. Method and Design. Children enrolled in the Cooperative Study of Sickle Cell Disease were evaluated with brain MRI and neuropsychological evaluation. Completed studies were obtained for 194 children, 135 with HbSS. MRIs were categorized according to the presence of T2-weighted, high-intensity images suggestive of infarct and were further categorized on the basis of a clinical history of cerebrovascular accident (CVA). An abnormal MRI but no clinical history of CVA was classified as a silent infarct. Neuropsychological evaluations included assessment of both global intellectual functioning and specific academic and neuropsychological functions. Results. Central nervous system (CNS) abnormalities were identified on MRI in 17.9% of the children (22.2% of children homozygous for HbS), and a clinical history of CVA (N = 9, 4.6%) was identified in only children with HbSS disease. Subsequent analyses examined only children with HbSS. Children with a history of CVA performed significantly poorer than children with silent infarcts or no MRI abnormality on most neuropsychological evaluation measures. Children with silent infarcts on MRI performed significantly poorer than children with no MRI abnormality on tests of arithmetic, vocabulary, and visual motor speed and coordination. Conclusions. These results substantiate the importance of careful evaluation, educational planning, and medical intervention for CNS-related complications in children with sickle cell disease.

Authors
Armstrong, FD; Jr, RJT; Wang, MDW; Zimmerman, MDR; Charles, H; Pegelow, MD; Miller, MDS; Moser, MDF; Bello, MDJ; Hurtig, A; Vass, K
MLA Citation
Armstrong, FD, Jr, RJT, Wang, MDW, Zimmerman, MDR, Charles, H, Pegelow, MD, Miller, MDS, Moser, MDF, Bello, MDJ, Hurtig, A, and Vass, K. "Cognitive functioning and brain magnetic resonance imaging in children with sickle cell disease." Pediatrics 97.6 I (1996): 864-870.
Source
scival
Published In
Pediatrics
Volume
97
Issue
6 I
Publish Date
1996
Start Page
864
End Page
870

Brain fluoxetine measurements using fluorine magnetic resonance spectroscopy in patients with social phobia.

Authors
Miner, CM; Davidson, JR; Potts, NL; Tupler, LA; Charles, HC; Krishnan, KR
MLA Citation
Miner, CM, Davidson, JR, Potts, NL, Tupler, LA, Charles, HC, and Krishnan, KR. "Brain fluoxetine measurements using fluorine magnetic resonance spectroscopy in patients with social phobia." Biol Psychiatry 38.10 (November 15, 1995): 696-698.
PMID
8555383
Source
pubmed
Published In
Biological Psychiatry
Volume
38
Issue
10
Publish Date
1995
Start Page
696
End Page
698
DOI
10.1016/0006-3223(95)00287-1

Nuclear magnetic resonance spectroscopy: a review of neuropsychiatric applications.

1. Magnetic resonance spectroscopy (MRS) is a powerful new neuropsychiatric research tool which allows for the noninvasive investigation of in vivo biochemistry. This review focuses on the recent applications of MRS to in vivo neuropsychiatric research. 2. The history of MRS as it has progressed from an in vitro method of biochemical analysis to its current in vivo research uses is presented. 3. A brief overview of the physical principles of MRS, including methods for spectral localization, is discussed. 4. Applications of the different MRS modalities (1H, 31P, 19F, 7Li, 13C and 23Na) to various neuropsychiatric disorders such as Alzheimer's disease, schizophrenia, affective disorders, acquired immunodeficiency disease, etc. are reviewed. The study of both fluorinated neuroleptics and the antidepressant fluoxetine using 19F MRS are discussed in greater detail. 5. Finally, potential future neuropsychiatric applications of MRS and specifically 19F MRS are presented.

Authors
Passe, TJ; Charles, HC; Rajagopalan, P; Krishnan, KR
MLA Citation
Passe, TJ, Charles, HC, Rajagopalan, P, and Krishnan, KR. "Nuclear magnetic resonance spectroscopy: a review of neuropsychiatric applications." Prog Neuropsychopharmacol Biol Psychiatry 19.4 (July 1995): 541-563. (Review)
PMID
8588055
Source
pubmed
Published In
Progress in Neuro-Psychopharmacology & Biological Psychiatry
Volume
19
Issue
4
Publish Date
1995
Start Page
541
End Page
563

International workshop on standardization in clinical MRS measurements: proceedings and recommendations.

Authors
Leach, MO; Arnold, D; Brown, TR; Charles, HC; de Certaines, JD; Evelhoch, JL; Margulis, AR; Negendank, WG; Nelson, SJ; Podo, F
MLA Citation
Leach, MO, Arnold, D, Brown, TR, Charles, HC, de Certaines, JD, Evelhoch, JL, Margulis, AR, Negendank, WG, Nelson, SJ, and Podo, F. "International workshop on standardization in clinical MRS measurements: proceedings and recommendations." Technol Health Care 2.4 (December 1994): 217-234.
PMID
7842307
Source
pubmed
Published In
Technology and health care : official journal of the European Society for Engineering and Medicine
Volume
2
Issue
4
Publish Date
1994
Start Page
217
End Page
234

Skeletal muscle pH assessed by biochemical and 31P-MRS methods during exercise and recovery in men.

The present study was designed to compare evaluation of skeletal muscle metabolism (vastus lateralis) evaluated by 31P-magnetic resonance spectroscopy (MRS) and biochemical analysis. During identical isometric knee extensor exercise protocols to fatigue in eight men, biopsy samples were taken at rest, peak exercise, and 32 s postexercise and 31P-MRS data were collected continuously for phosphocreatine (PCr), pH, ATP, and P(i) at 8- or 32-s intervals. There was no difference in ATP or pH measurements between the two techniques at rest, during peak exercise, or in recovery. Corresponding measurements of pH by the two techniques were closely related (r = 0.88, P < 0.01), and pH measured by 31P-MRS was closely related to muscle lactate accumulation (r = -0.84, P < 0.001). The level of PCr at peak exercise, expressed as a percentage of the baseline value, was not different between the two techniques (42 +/- 15 vs. 46 +/- 15%). The results indicate that, in skeletal muscle in normal subjects, 1) measurements of pH and PCr at rest and during exercise do not differ between the 31P-MRS and biopsy techniques and 2) muscle pH measured by 31P-MRS is closely related to lactate accumulation in men. Our data suggest that direct comparison of results of studies of exercise metabolism using these two techniques is warranted.

Authors
Sullivan, MJ; Saltin, B; Negro-Vilar, R; Duscha, BD; Charles, HC
MLA Citation
Sullivan, MJ, Saltin, B, Negro-Vilar, R, Duscha, BD, and Charles, HC. "Skeletal muscle pH assessed by biochemical and 31P-MRS methods during exercise and recovery in men." J Appl Physiol (1985) 77.5 (November 1994): 2194-2200.
PMID
7868433
Source
pubmed
Published In
Journal of applied physiology (Bethesda, Md. : 1985)
Volume
77
Issue
5
Publish Date
1994
Start Page
2194
End Page
2200

Brain choline in depression: in vivo detection of potential pharmacodynamic effects of antidepressant therapy using hydrogen localized spectroscopy.

1. Seven subjects with depression and matched controls were studied using proton spectroscopy to test the hypothesis that choline will be elevated in depression. 2. The proton spectroscopy was repeated after recovery from depression. 3. The study confirmed a state dependent increase in choline in the brain. 4. This change may be used as an in vivo marker of change in depression.

Authors
Charles, HC; Lazeyras, F; Krishnan, KR; Boyko, OB; Payne, M; Moore, D
MLA Citation
Charles, HC, Lazeyras, F, Krishnan, KR, Boyko, OB, Payne, M, and Moore, D. "Brain choline in depression: in vivo detection of potential pharmacodynamic effects of antidepressant therapy using hydrogen localized spectroscopy." Prog Neuropsychopharmacol Biol Psychiatry 18.7 (November 1994): 1121-1127.
PMID
7846284
Source
pubmed
Published In
Progress in Neuro-Psychopharmacology & Biological Psychiatry
Volume
18
Issue
7
Publish Date
1994
Start Page
1121
End Page
1127

International Workshop on Standardization in Clinical Magnetic Resonance Spectroscopy Measurements: proceedings and recommendations.

Authors
Leach, MO; Arnold, D; Brown, TR; Charles, HC; de Certaines, JD; Evelhoch, JL; Margulis, AR; Negendank, WG; Nelson, SJ; Podo, F
MLA Citation
Leach, MO, Arnold, D, Brown, TR, Charles, HC, de Certaines, JD, Evelhoch, JL, Margulis, AR, Negendank, WG, Nelson, SJ, and Podo, F. "International Workshop on Standardization in Clinical Magnetic Resonance Spectroscopy Measurements: proceedings and recommendations." Acad Radiol 1.2 (October 1994): 171-186.
PMID
9419483
Source
pubmed
Published In
Academic Radiology
Volume
1
Issue
2
Publish Date
1994
Start Page
171
End Page
186

Proton spectroscopy of human brain: effects of age and sex.

1. The present study was done to assess the brain metabolites measured by proton magnetic resonance spectroscopy (MRS) in normal individuals. 2. Proton spectroscopy STEAM voxel technique with chemical shift imaging was used to provide localized metabolic information from the brains of 34 normal volunteers (15 males) between the ages of 21 and 75 years. 3. Choline, Creatine and N-acetyl aspartate (NAA) was lower in white matter than gray matter. Choline/NAA and choline/creatine ratios were also lower in white matter. The choline, creatine and NAA were lower in older subjects in the voxel representing cortical and subcortical gray matter. There were no differences between males and females. 4. This preliminary study suggests that age matching is essential for comparative studies of disease states using proton MRS.

Authors
Charles, HC; Lazeyras, F; Krishnan, KR; Boyko, OB; Patterson, LJ; Doraiswamy, PM; McDonald, WM
MLA Citation
Charles, HC, Lazeyras, F, Krishnan, KR, Boyko, OB, Patterson, LJ, Doraiswamy, PM, and McDonald, WM. "Proton spectroscopy of human brain: effects of age and sex." Prog Neuropsychopharmacol Biol Psychiatry 18.6 (October 1994): 995-1004.
PMID
7824764
Source
pubmed
Published In
Progress in Neuro-Psychopharmacology & Biological Psychiatry
Volume
18
Issue
6
Publish Date
1994
Start Page
995
End Page
1004

Relative accuracy and reproducibility of regional MRI brain volumes for point-counting methods.

Volumetric magnetic resonance imaging (MRI) methods for the measurement of various neuroanatomical regions are of great interest in studies of neuropsychiatric disorders. Both manual and semiautomated methods have been developed. Manual methods include tracing and point counting. Point counting methods are widely used in post-mortem and microscopy studies. Point counting has been well validated for these purposes. In this article, we report in a series of separate studies the accuracy and reproducibility of point-counting methods. Absolute accuracy was evaluated with a spherical phantom. Accuracy and time efficiency were subsequently assessed with an anatomically realistic phantom and various size grids. The point-counting method was also compared to a tracing method. Finally, the reproducibility of the point-counting method for the caudate and putamen was evaluated on four subjects in a test-retest experiment. These studies provide an estimate of the accuracy and time efficiency of point-counting methods. The test-retest reliability was also high for both caudate and putamen. Findings suggest that point counting is a reliable and efficient method for estimating volumes.

Authors
MacFall, JR; Byrum, CE; Parashos, I; Early, B; Charles, HC; Chittilla, V; Boyko, OB; Upchurch, L; Krishnan, KR
MLA Citation
MacFall, JR, Byrum, CE, Parashos, I, Early, B, Charles, HC, Chittilla, V, Boyko, OB, Upchurch, L, and Krishnan, KR. "Relative accuracy and reproducibility of regional MRI brain volumes for point-counting methods." Psychiatry Res 55.3 (September 1994): 167-177.
PMID
7870856
Source
pubmed
Published In
Psychiatry Research
Volume
55
Issue
3
Publish Date
1994
Start Page
167
End Page
177

MONITORING OF RESPONSE TO NEOADJUVANT THERAPY OF SOFT-TISSUE AND MUSCULOSKELETAL SARCOMAS USING F-18-FDG PET

Authors
JONES, DN; BRIZEL, DM; CHARLES, HC; DEWHIRST, MW; FRIEDMAN, HS; MCCOWAGE, G; PRESCOTT, DM; SOSTMAN, HD; COLEMAN, RE
MLA Citation
JONES, DN, BRIZEL, DM, CHARLES, HC, DEWHIRST, MW, FRIEDMAN, HS, MCCOWAGE, G, PRESCOTT, DM, SOSTMAN, HD, and COLEMAN, RE. "MONITORING OF RESPONSE TO NEOADJUVANT THERAPY OF SOFT-TISSUE AND MUSCULOSKELETAL SARCOMAS USING F-18-FDG PET." JOURNAL OF NUCLEAR MEDICINE 35.5 (May 1994): P38-P38.
Source
wos-lite
Published In
Journal of nuclear medicine : official publication, Society of Nuclear Medicine
Volume
35
Issue
5
Publish Date
1994
Start Page
P38
End Page
P38

Therapy monitoring in human and canine soft tissue sarcomas using magnetic resonance imaging and spectroscopy.

PURPOSE: The goals of this study were to determine whether magnetic resonance parameters (a) can identify early during therapy those patients most likely to respond to hyperthermia and radiotherapy, (b) can provide prior to or early during therapy information about the temperature distributions which can be obtained in patients receiving hyperthermia, and (c) can provide an understanding of the effects of hyperthermia on tumor metabolic status. METHODS AND MATERIALS: Twenty-one human patients and 10 canine patients with soft tissue sarcomas treated with preoperative hyperthermia and radiation had a series of magnetic resonance imaging and phosphorous spectroscopy studies done. To address the goals for both the human and canine populations, changes in mean T2 relaxation times, pH, and various phosphometabolite ratios from the pretreatment (Study 1) to the post first hyperthermia study (Study 2) were correlated with treatment outcome; pretreatment magnetic resonance parameters and changes in magnetic resonance parameters (Study 2-Study 1) were compared with various cumulative thermal descriptors; and thermal descriptors of the first hyperthermia were compared with changes in magnetic resonance phosphometabolite ratios. RESULTS: A decrease in adenosine triphosphate/phosphomonoester from study 1 to study 2 is associated with a greater chance of > or = 95% necrosis in surgical resected tumors from human patients, but no significant relationships were observed between changes in tumor pH or phosphometabolite ratios and time to local failure in dogs. Pretreatment magnetic resonance parameters correlated with various thermal dose descriptors in canines but not in humans. Change in adenosine triphosphate/inorganic phosphate and phosphomonoester signal to noise ratio correlated with cumulative thermal descriptors in dogs and humans, respectively. In dogs only, increases in thermal dose resulted in decreases in high energy phosphometabolites. CONCLUSION: Changes in magnetic resonance parameters early during therapy may be predictive of treatment outcome. Pretreatment and changes in magnetic resonance parameters appear to predict how well a tumor will be heated during hyperthermia. Magnetic resonance spectroscopy also appears to be a useful tool to study the effects of various thermal doses on tumor metabolic status.

Authors
Prescott, DM; Charles, HC; Sostman, HD; Dodge, RK; Thrall, DE; Page, RL; Tucker, JA; Harrelson, JM; Leopold, KA; Oleson, JR
MLA Citation
Prescott, DM, Charles, HC, Sostman, HD, Dodge, RK, Thrall, DE, Page, RL, Tucker, JA, Harrelson, JM, Leopold, KA, and Oleson, JR. "Therapy monitoring in human and canine soft tissue sarcomas using magnetic resonance imaging and spectroscopy." Int J Radiat Oncol Biol Phys 28.2 (January 15, 1994): 415-423.
PMID
8276656
Source
pubmed
Published In
International Journal of Radiation Oncology, Biology, Physics
Volume
28
Issue
2
Publish Date
1994
Start Page
415
End Page
423

MR imaging and spectroscopy for prognostic evaluation in soft-tissue sarcomas.

PURPOSE: To enable prediction of tumor response to a particular treatment. MATERIALS AND METHODS: The authors studied the value of hydrogen-1 T2 and phosphorus-31 magnetic resonance (MR) spectroscopic metabolic determinations as indicators of prognosis in 20 humans and 10 dogs with soft-tissue sarcomas. All patients underwent combined fractionated radiation therapy and hyperthermia. Surgical resection of the entire tumor in humans allowed comparison of pretherapy T2 and MR spectroscopic parameters with subsequent histologic findings. Long-term clinical follow-up (no surgical intervention) was available with the dogs and allowed comparison of pretherapy pH with the duration of local relapse-free survival. RESULTS: A relationship exists between pretherapy pH and T2 and ultimate tumor necrosis in humans and pretherapy pH and time elapsed until local failure in dogs. CONCLUSION: MR imaging and spectroscopy could be useful in the prognosis of patients with soft-tissue sarcomas before therapy is initiated.

Authors
Sostman, HD; Prescott, DM; Dewhirst, MW; Dodge, RK; Thrall, DE; Page, RL; Tucker, JA; Harrelson, JM; Reece, G; Leopold, KA
MLA Citation
Sostman, HD, Prescott, DM, Dewhirst, MW, Dodge, RK, Thrall, DE, Page, RL, Tucker, JA, Harrelson, JM, Reece, G, and Leopold, KA. "MR imaging and spectroscopy for prognostic evaluation in soft-tissue sarcomas." Radiology 190.1 (January 1994): 269-275.
PMID
8259418
Source
pubmed
Published In
Radiology
Volume
190
Issue
1
Publish Date
1994
Start Page
269
End Page
275
DOI
10.1148/radiology.190.1.8259418

Effects of therapy on the 1H NMR spectrum of a human glioma line.

Currently it is difficult to predict the efficacy of any therapeutic modality in individual patients. If it could be shown that successful therapy causes some chemical alteration in the tumor before gross alteration in size becomes radiologically visible, the therapeutic regimen could potentially be modified, sparing the patients longer trials of ineffective therapy. We used proton nuclear magnetic resonance spectroscopy to detect the presence of simple metabolites (such as lactic acid, creatine/phosphocreatine, N-acetyl aspartate, and the "choline" pool) in extracts of a human glioma grown subcutaneously in athymic ("nu/nu") mice. By comparing the tumor spectra obtained from untreated mice with tumor spectra from mice treated with chemotherapy or irradiation, we have shown a significant decrease in the lactate/creatine and lactate/choline values in tumors of similar size following treatment. Such information could prove valuable as a means of monitoring tumor therapy when obtained noninvasively from spatially localized in vivo spectra.

Authors
Cazzaniga, S; Schold, SC; Sostman, HD; Charles, HC
MLA Citation
Cazzaniga, S, Schold, SC, Sostman, HD, and Charles, HC. "Effects of therapy on the 1H NMR spectrum of a human glioma line." Magn Reson Imaging 12.6 (1994): 945-950.
PMID
7968293
Source
pubmed
Published In
Magnetic Resonance Imaging
Volume
12
Issue
6
Publish Date
1994
Start Page
945
End Page
950

Magnetic resonance spectroscopy in social phobia: preliminary findings.

Proton localized magnetic resonance spectroscopy was studied in 20 social phobics and 20 age- and sex-matched controls. Stimulated Echo Acquisition Mode volume element localization was used with chemical shift imaging. Choline and creatine signal-to-noise ratios (SNRs) were significantly lower in social phobia than in controls in subcortical, thalamic, and caudate areas. In the social phobic group, N-acetylaspartate (NAA) SNR was significantly lower in cortical and subcortical regions, and ratios of NAA to other metabolites were lower in social phobia. Choline, creatine, and NAA SNRs were inversely correlated to total social phobia and fear symptoms, as measured by the Brief Social Phobia Scale, in the thalamic and noncortical gray areas. In a small number of patients who received clonazepam, posttreatment SNRs generally increased relative to baseline. Our results suggest a promising place for magnetic resonance spectroscopy in social phobia and also indicate potential pharmacodynamic uses of this technique.

Authors
Davidson, JR; Krishnan, KR; Charles, HC; Boyko, O; Potts, NL; Ford, SM; Patterson, L
MLA Citation
Davidson, JR, Krishnan, KR, Charles, HC, Boyko, O, Potts, NL, Ford, SM, and Patterson, L. "Magnetic resonance spectroscopy in social phobia: preliminary findings." J Clin Psychiatry 54 Suppl (December 1993): 19-25.
PMID
8276746
Source
pubmed
Published In
Journal of Clinical Psychiatry
Volume
54 Suppl
Publish Date
1993
Start Page
19
End Page
25

Manipulation of intra- and extracellular pH in spontaneous canine tumours by use of hyperglycaemia.

We evaluated the use of hyperglycaemia to reduce tumour pH in dog with spontaneous tumours. Dogs were randomized to two groups: control and glucose. Intravenous administration of 20% glucose was used to induce and maintain hyperglycaemia. Extra- and intracellular tumour pH were measured using interstitial pH microelectrodes and 31P-MRS, respectively. During the administration of glucose, the mean (+/- SEM) blood glucose concentration was 419.8 (+/- 32.8) and 121.1 (+/- 8.0) mg/dl for the glucose and control groups, respectively. The mean extracellular tumour pH before and following 90 min of hyperglycaemia was 7.15 (+/- 0.08) and 7.15 (+/- 0.09). During consecutive measurements, intracellular tumour pH did not change significantly for the control group or the group subjected to hyperglycaemic manipulation. In contradistinction to previous rodent studies, our results demonstrate that hyperglycaemia alone is not sufficient to manipulate either intra- (pHi) or extracellular (pHe) hydrogen ion concentration in spontaneous canine soft tissue tumours.

Authors
Prescott, DM; Charles, HC; Sostman, HD; Page, RL; Thrall, DE; Moore, D; Oleson, JR; Dewhirst, MW
MLA Citation
Prescott, DM, Charles, HC, Sostman, HD, Page, RL, Thrall, DE, Moore, D, Oleson, JR, and Dewhirst, MW. "Manipulation of intra- and extracellular pH in spontaneous canine tumours by use of hyperglycaemia." Int J Hyperthermia 9.5 (September 1993): 745-754.
PMID
8245584
Source
pubmed
Published In
International Journal of Hyperthermia (Informa)
Volume
9
Issue
5
Publish Date
1993
Start Page
745
End Page
754

Biology of social phobia

Authors
Davidson, JRT; Potts, N; Krishnan, R; Boyko, O; Charles, C; Smith, R; Ford, S; Tupler, LA; Wilson, W
MLA Citation
Davidson, JRT, Potts, N, Krishnan, R, Boyko, O, Charles, C, Smith, R, Ford, S, Tupler, LA, and Wilson, W. "Biology of social phobia." European Neuropsychopharmacology 3.3 (1993): 192-193.
Source
scival
Published In
European Neuropsychopharmacology
Volume
3
Issue
3
Publish Date
1993
Start Page
192
End Page
193

Non-invasive thermometry using magnetic resonance diffusion imaging: potential for application in hyperthermic oncology.

The proposition to use non-invasive thermometry based on magnetic resonance diffusion imaging for applications in therapeutic hyperthermia is examined. The measurement of proton motion predominantly associated with the self-diffusion of water can be characterized by a Boltzmann temperature dependence (i.e. e-Ea/kT). The activation energy (Ea) is on the order of 0.2 eV and, for a restricted range (approximately 30 degrees) at a base temperature of approximately 300 K, the relationship between the effective diffusion coefficient and temperature is approximately linear. This response has been empirically demonstrated in water-based gel phantoms using magnetic resonance imaging (MRI). Additionally, it is feasible to have compatibility between radiofrequency (RF) heating devices and MRI equipment. An MRI-compatible heating applicator that includes a hexagonal array of coherently phased dipoles was assembled. This heating array easily fits into a standard 1.5 T head imaging coil (diameter 28 cm). The RF fields associated with heating (130 MHz) and imaging (64 MHz) were decoupled using bandpass filters providing isolation in excess of 100 dB. This isolation was sufficient to allow simultaneous imaging and RF heating without deterioration of the image signal-to-noise ratio. In this report temperature, spatial and time resolution achieved in phantom are examined in order to assess the potential for using this non-invasive temperature measurement in applications of hyperthermic oncology. Using this system and conventional multi-slice imaging techniques, 0.5 degrees C resolution in a voxel size of less than 1 cm3 has been achieved using an acquisition time of 4.15 min.

Authors
Samulski, TV; MacFall, J; Zhang, Y; Grant, W; Charles, C
MLA Citation
Samulski, TV, MacFall, J, Zhang, Y, Grant, W, and Charles, C. "Non-invasive thermometry using magnetic resonance diffusion imaging: potential for application in hyperthermic oncology." Int J Hyperthermia 8.6 (November 1992): 819-829.
PMID
1479207
Source
pubmed
Published In
International Journal of Hyperthermia (Informa)
Volume
8
Issue
6
Publish Date
1992
Start Page
819
End Page
829

Measurement of preretinal oxygen tension in the vitrectomized human eye using fluorine-19 magnetic resonance spectroscopy.

We obtained oxygen measurements from a human eye that contained small preretinal droplets of perfluorotributylamine (FTBA) by using fluorine-19 magnetic resonance spectroscopy. These droplets were the remainder of a larger volume of FTBA that was used as an intraoperative retinal tamponade during retinal detachment repair. The spin-lattice relaxation rate ([T1]-1) of the FTBA fluorine nuclide was obtained that could then be related, by direct proportionality, to droplet PO2. With the patient in a supine position, the droplets could be positioned over the macula in the preretinal vitreous space, whereon the FTBA PO2 could be influenced by the preretinal oxygen concentration. Preretinal PO2 values, derived from magnetic resonance spectroscopy, were in the range of 6 to 9 mm Hg, although multiple components were identified that were suggestive of a heterogeneous distribution of PO2 values in the population of droplets. To our knowledge, this investigation is the first to demonstrate the feasibility of this approach to performing long-term, noninvasive preretinal oxygen measurements in the vitrectomized human eye by using small droplets of a liquid perfluorochemical.

Authors
Wilson, CA; Berkowitz, BA; McCuen, BW; Charles, HC
MLA Citation
Wilson, CA, Berkowitz, BA, McCuen, BW, and Charles, HC. "Measurement of preretinal oxygen tension in the vitrectomized human eye using fluorine-19 magnetic resonance spectroscopy." Arch Ophthalmol 110.8 (August 1992): 1098-1100.
PMID
1497523
Source
pubmed
Published In
Archives of Ophthalmology
Volume
110
Issue
8
Publish Date
1992
Start Page
1098
End Page
1100

AN OVERVIEW OF DIGITAL SPECTROMETERS FOR MR IMAGING

Authors
HOLLAND, GN; MACFALL, JR; CHARLES, HC; DIXON, WT; GLOVER, GH; HOLLAND, GN
MLA Citation
HOLLAND, GN, MACFALL, JR, CHARLES, HC, DIXON, WT, GLOVER, GH, and HOLLAND, GN. "AN OVERVIEW OF DIGITAL SPECTROMETERS FOR MR IMAGING." JMRI-JOURNAL OF MAGNETIC RESONANCE IMAGING 2.2 (1992): 241-246.
Source
wos-lite
Published In
Journal of Magnetic Resonance Imaging
Volume
2
Issue
2
Publish Date
1992
Start Page
241
End Page
246
DOI
10.1002/jmri.1880020221

Cine phase-contrast magnetic resonance imaging for analysis of flow phenomena in experimental aortic dissection.

Using a 1.5 T magnetic resonance imaging (MRI) system, cine phase-contrast and magnitude images were obtained in three phantoms that simulated different anatomic configurations of aortic dissection. The dissection phantoms were made of compliant materials, and pulsatile flow was used in all experiments. Phantoms differed only in the location of the fenestration between the true and false lumens (I: an upstream "entry" only, II: both upstream "entry" and downstream "re-entry," and III: a downstream "entry" only). Flow jets, flap motion, and wave propagation were clearly visualized in cine MR images of each phantom, and quantitatively analyzed with reference to the stimulated cardiac cycle of the pump. Flow in the false lumen was always bidirectional. Upstream and downstream flow waves collided and dispersed within the false lumen. Flow through the false lumen was the same in phantoms I and II, and least in phantom III. The average area of the true lumen was largest in phantom III and smallest in I. Phantom I had the highest overall flow rate in the false lumen and greatest change in false lumen size during the cardiac cycle, while the downstream "entry" phantom had the lowest of both parameters. Flow phenomena in aortic dissections can be studied by cine phase-contrast MRI.

Authors
Iwai, F; Sostman, HD; Evans, AJ; Nadel, SN; Hedlund, LW; Beam, CA; Charles, HC; Spritzer, CE
MLA Citation
Iwai, F, Sostman, HD, Evans, AJ, Nadel, SN, Hedlund, LW, Beam, CA, Charles, HC, and Spritzer, CE. "Cine phase-contrast magnetic resonance imaging for analysis of flow phenomena in experimental aortic dissection." Invest Radiol 26.12 (December 1991): 1071-1078.
PMID
1765440
Source
pubmed
Published In
Investigative Radiology
Volume
26
Issue
12
Publish Date
1991
Start Page
1071
End Page
1078

Bone and soft tissue lesions: diagnosis with combined H-1 MR imaging and P-31 MR spectroscopy.

Authors
Sostman, HD; Charles, HC
MLA Citation
Sostman, HD, and Charles, HC. "Bone and soft tissue lesions: diagnosis with combined H-1 MR imaging and P-31 MR spectroscopy." Invest Radiol 26.8 (August 1991): 769-770.
PMID
1917417
Source
pubmed
Published In
Investigative Radiology
Volume
26
Issue
8
Publish Date
1991
Start Page
769
End Page
770

Evaluation of BA1112 rhabdomyosarcoma oxygenation with microelectrodes, optical spectrophotometry, radiosensitivity, and magnetic resonance spectroscopy.

We studied tumor tissue oxygenation in the BA1112 rhabdomyosarcoma using micro-electrode pO2 measurements, optical spectrophotometry, analyses of cell survival after irradiation, and 31P magnetic resonance spectroscopy (MRS). Studies were carried out in WAG/Rij/Y rats breathing normoxic, hypoxic, and hyperoxic gas mixtures with and without iv administration of perfluorochemical. Significant changes in tissue oxygenation and metabolic status were found when pO2 values, optical measurements of hemoglobin saturation and cytochrome a, a3 reduction-oxidation, radiation cell survival determinations, and MRS measurements of phosphometabolite ratios were obtained in rats breathing different gas mixtures. Inhalation of 100% O2 caused increases in tumor pO2, hemoglobin saturation, cytochrome a, a3 oxidation, tumor radiosensitivity, and PCr/Pi, NTP/Pi, and PDE/Pi ratios. Such changes were augmented by pretreatment with iv perfluorochemicals. Inhalation of hypoxic gas mixtures resulted in reductions in the above parameters. These results indicate that tissue oxygenation can be manipulated reproducibly in the BA1112 rhabdomyosarcoma and suggest that 31P MRS can be used to monitor changes in tumor oxygenation in this model system.

Authors
Sostman, HD; Rockwell, S; Sylvia, AL; Madwed, D; Cofer, G; Charles, HC; Negro-Vilar, R; Moore, D
MLA Citation
Sostman, HD, Rockwell, S, Sylvia, AL, Madwed, D, Cofer, G, Charles, HC, Negro-Vilar, R, and Moore, D. "Evaluation of BA1112 rhabdomyosarcoma oxygenation with microelectrodes, optical spectrophotometry, radiosensitivity, and magnetic resonance spectroscopy." Magn Reson Med 20.2 (August 1991): 253-267.
PMID
1775051
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
20
Issue
2
Publish Date
1991
Start Page
253
End Page
267

Muscle activity localization with 31P spectroscopy and calculated T2-weighted 1H images.

Using 31P spectroscopy and magnetic resonance imaging (MRI), the authors studied changes in muscle phosphorous metabolites and T2 with isometric knee extension to evaluate the potential role of T2 images in coil placement for exercise spectroscopy studies. Increased signal intensity was visible in active muscles on T2 images after exercise. Calculated T2-weighted values were elevated immediately after exercise in the quadriceps (P less than .01). T2 increases for individual quadricep muscles varied, with the largest changes in the rectus femoris and the least in the vastus lateralis. 31P spectroscopy studies demonstrated similar findings: percent change in T2 correlated positively with inorganic phosphorus to phosphocreatine ratio (Pi/PCr) (r = 0.89, P less than .01) and negatively with pH (r = -0.88, P less than .01). The correlations between imaging and spectroscopy suggest that T2 images may allow more precise placement of phosphorous coils in exercise studies. The heterogeneity of T2 changes within the quadriceps with exercise suggests that assumptions about muscle activity may be misleading. T2 images may provide muscle activity verification for exercise studies.

Authors
Weidman, ER; Charles, HC; Negro-Vilar, R; Sullivan, MJ; MacFall, JR
MLA Citation
Weidman, ER, Charles, HC, Negro-Vilar, R, Sullivan, MJ, and MacFall, JR. "Muscle activity localization with 31P spectroscopy and calculated T2-weighted 1H images." Invest Radiol 26.4 (April 1991): 309-316.
PMID
2032818
Source
pubmed
Published In
Investigative Radiology
Volume
26
Issue
4
Publish Date
1991
Start Page
309
End Page
316

1990 ARRS Executive Council Award. Renal transplant rejection: diagnosis with 31P MR spectroscopy.

We evaluated the role of 31P MR spectroscopy in the diagnosis of renal transplant allograft dysfunction. Thirty-six 31P MR spectroscopy examinations were prospectively performed in 35 patients with renal allografts. The study was performed in two phases. In the first phase, 12 transplant recipients with normal graft function were studied as normal controls. During phase two, 24 31P MR spectroscopy studies were performed in patients at the time of renal transplant biopsy for allograft dysfunction. Twenty-one of these studies were technically adequate. Pathologic analysis of the biopsy specimens showed evidence of allograft rejection in 14 and no rejection in seven. Various phosphorus metabolite ratios were calculated for each patient, including phosphodiesters/phosphomonoesters (PDE/PME), phosphomonoesters/inorganic phosphate (PME/Pi), and inorganic phosphate/adenosine triphosphate (Pi/ATP). The PDE/PME and Pi/ATP ratios in the allografts with rejection differed significantly from the corresponding metabolite ratios in patients without rejection (p = .017 and p = .024, respectively). A PDE/PME ratio exceeding 0.8 had a sensitivity of 100% and specificity of 86% for predicting rejection. A Pi/ATP ratio greater than 0.6 had a sensitivity of 72% and a specificity of 86% for predicting rejection. We conclude that 31P MR spectroscopy may be useful as a noninvasive method for evaluating renal metabolism during episodes of transplant allograft dysfunction.

Authors
Grist, TM; Charles, HC; Sostman, HD
MLA Citation
Grist, TM, Charles, HC, and Sostman, HD. "1990 ARRS Executive Council Award. Renal transplant rejection: diagnosis with 31P MR spectroscopy." AJR Am J Roentgenol 156.1 (January 1991): 105-112.
PMID
1898541
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
156
Issue
1
Publish Date
1991
Start Page
105
End Page
112
DOI
10.2214/ajr.156.1.1898541

More on the feasibility of using MRI for noninvasive thermometry in hyperthermia

A combination of RF heating and MR imaging equipment has been constructed in a fashion that allows simultaneous heating and MR diffusion imaging. Isolation between the RF heating and RF imaging frequencies is accomplished by means of filtering. This system has allowed a systematic estimate of temperature resolution and spatial resolution to be made using noninvasive MR tomography in a phantom model. The initial data indicates that 0.8°C resolution in ≤ 1 cm3 voxel is feasible using standard imaging techniques and an acquisition time of approximately 2 minutes.

Authors
Samulski, TV; MacFall, J; Zhang, Y; Palmer, D; Charles, C; Grant, W
MLA Citation
Samulski, TV, MacFall, J, Zhang, Y, Palmer, D, Charles, C, and Grant, W. "More on the feasibility of using MRI for noninvasive thermometry in hyperthermia." American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD 189 (1991): 57-60.
Source
scival
Published In
American Society of Mechanical Engineers, Heat Transfer Division, (Publication) HTD
Volume
189
Publish Date
1991
Start Page
57
End Page
60

Renal transplant rejection: Diagnosis with 31P MR spectroscopy

We evaluated the role of 31P MR spectroscopy in the diagnosis of renal transplant allograft dysfunction. Thirty-six 31P MR spectroscopy examinations were prospectively pertormed in 35 patients with renal allografts. The study was performed in two phases. In the first phase, 12 transplant recipients with normal graft function were studied as normal controls. During phase two 24 31P MR spectroscopy studies were performed in patients at the time of renal transplant biopsy for allograft dysfunction. Twenty-one of these studies were technically adequate. Pathologic analysis of the biopsy specimens showed evidence of allograft rejection in 14 and no rejection in seven. Various phosphorus metabolite ratios were calculated for each patient, including phosphodiesters/phosphomonoesters (PDE/PME), phosphomonoesters/inorganic phosphate (PME/Pi), and inorganic phosphate/adenosine triphosphate (Pi/ATP). The PDE/PME and Pi/ATP ratios in the allografts with rejection differed significantly from the corresponding metabolite ratios in patients without rejection (P = .017 and P = .024, respectively). A PDE/PME ratio exceeding 0.8 had a sensitivity of 100% and specificity of 86% for predicting rejection. A Pi/ATP ratio greater than 0.6 had a sensitivity of 72% and a specificity of 86% for predicting rejection. We conclude that 31P MR spectroscopy may be useful as a noninvasive method for evaluating renal metabolism during episodes of transplant allograft dysfunction.

Authors
Grist, TM; Charles, HC; Sostman, HD
MLA Citation
Grist, TM, Charles, HC, and Sostman, HD. "Renal transplant rejection: Diagnosis with 31P MR spectroscopy." American Journal of Roentgenology 156.1 (1991): 105-112.
Source
scival
Published In
American Journal of Roentgenology
Volume
156
Issue
1
Publish Date
1991
Start Page
105
End Page
112

Bone and soft tissue lesions: Diagnosis with combined H-1 MR imaging and P-31 MR spectroscopy: Comments and authors' response

Authors
Sostman, HD; Charles, HC; Negendank, WG; Crowley, MG; Ryan, JR; Keller, NA; Evelhoch, JL
MLA Citation
Sostman, HD, Charles, HC, Negendank, WG, Crowley, MG, Ryan, JR, Keller, NA, and Evelhoch, JL. "Bone and soft tissue lesions: Diagnosis with combined H-1 MR imaging and P-31 MR spectroscopy: Comments and authors' response." Investigative Radiology 26.8 (1991): 769-770.
Source
scival
Published In
Investigative Radiology
Volume
26
Issue
8
Publish Date
1991
Start Page
769
End Page
770

Soft-tissue sarcomas: detection of metabolic heterogeneity with P-31 MR spectroscopy.

Regional variations in metabolic parameters derived with multivoxel, localized phosphorus-31 magnetic resonance (MR) spectroscopy in spontaneous human-soft-tissue sarcomas were compared with variations in the same parameters in normal human legs. In addition, multivoxel P-31 MR spectroscopy of transplanted rodent sarcomas and microelectrode measurement of pH and PO2 in several locations within them were performed, and, when appropriate, results were compared with the clinical data. Striking voxel-voxel variability in parameters derived with P-31 spectroscopy was found in tumors, with less marked variability seen in normal legs. In the rodent tumors, spatial variations also were found in pH and PO2 measured by means of microelectrodes. These data are consistent with the results of regional measurements in tumors by means of other methods and suggest that clinical MR spectroscopic studies of tumors may need to consider the variability within malignant lesions.

Authors
Sostman, HD; Charles, HC; Rockwell, S; Leopold, K; Beam, C; Madwed, D; Dewhirst, M; Cofer, G; Moore, D; Burn, R
MLA Citation
Sostman, HD, Charles, HC, Rockwell, S, Leopold, K, Beam, C, Madwed, D, Dewhirst, M, Cofer, G, Moore, D, and Burn, R. "Soft-tissue sarcomas: detection of metabolic heterogeneity with P-31 MR spectroscopy." Radiology 176.3 (September 1990): 837-843.
PMID
2389045
Source
pubmed
Published In
Radiology
Volume
176
Issue
3
Publish Date
1990
Start Page
837
End Page
843
DOI
10.1148/radiology.176.3.2389045

Noninvasive differentiation of tumors with use of localized H-1 spectroscopy in vivo: initial experience in patients with cerebral tumors.

Authors
Sostman, HD; Charles, HC
MLA Citation
Sostman, HD, and Charles, HC. "Noninvasive differentiation of tumors with use of localized H-1 spectroscopy in vivo: initial experience in patients with cerebral tumors." Invest Radiol 25.9 (September 1990): 1047-1050.
PMID
2211049
Source
pubmed
Published In
Investigative Radiology
Volume
25
Issue
9
Publish Date
1990
Start Page
1047
End Page
1050

Soft-tissue sarcomas: MR imaging and MR spectroscopy for prognosis and therapy monitoring. Work in progress.

The authors studied the usefulness of hydrogen-1 T2 measurements and phosphorus-31 magnetic resonance (MR) spectroscopy as indicators of prognosis and monitors of response to therapy in a group of patients with soft-tissue sarcomas. All eight patients were treated with combined local hyperthermia and fractionated radiation therapy, followed by surgical resection of the tumor. Each patient underwent T2 measurements and five patients underwent MR spectroscopy (phase encoded in one dimension) before treatment, after the first hyperthermia treatment, at the end of the therapy course, and just before surgery. Catheter thermometry was performed at each hyperthermia treatment. The T2 and MR spectroscopic variables were compared with thermometric data and the histologic findings from the complete surgical specimen. Changes in T2 correlated with histologic grade of tumor and thermometric data. The pretherapy tumor pH correlated positively, and changes during therapy in pH, ratio of phosphocreatine to inorganic phosphate (Pi), ratio of nucleoside triphosphate to Pi, and the phosphomonoester signal-to-noise ratio correlated negatively, with the percentage of tumor necrosis on the surgical specimen. These preliminary data suggest MR imaging and MR spectroscopy may be useful in the evaluation of such patients before and during therapy.

Authors
Dewhirst, MW; Sostman, HD; Leopold, KA; Charles, HC; Moore, D; Burn, RA; Tucker, JA; Harrelson, JM; Oleson, JR
MLA Citation
Dewhirst, MW, Sostman, HD, Leopold, KA, Charles, HC, Moore, D, Burn, RA, Tucker, JA, Harrelson, JM, and Oleson, JR. "Soft-tissue sarcomas: MR imaging and MR spectroscopy for prognosis and therapy monitoring. Work in progress." Radiology 174.3 Pt 1 (March 1990): 847-853.
PMID
2154837
Source
pubmed
Published In
Radiology
Volume
174
Issue
3 Pt 1
Publish Date
1990
Start Page
847
End Page
853
DOI
10.1148/radiology.174.3.2154837

SOFT-TISSUE SARCOMAS - MR IMAGING AND MR SPECTROSCOPY FOR PROGNOSIS AND THERAPY MONITORING - WORK IN PROGRESS

Authors
DEWHIRST, MW; SOSTMAN, HD; LEOPOLD, KA; CHARLES, HC; MOORE, D; BURN, RA; TUCKER, JA; HARRELSON, JM; OLESON, JR
MLA Citation
DEWHIRST, MW, SOSTMAN, HD, LEOPOLD, KA, CHARLES, HC, MOORE, D, BURN, RA, TUCKER, JA, HARRELSON, JM, and OLESON, JR. "SOFT-TISSUE SARCOMAS - MR IMAGING AND MR SPECTROSCOPY FOR PROGNOSIS AND THERAPY MONITORING - WORK IN PROGRESS." RADIOLOGY 174.3 (March 1990): 847-853.
Source
wos-lite
Published In
Radiology
Volume
174
Issue
3
Publish Date
1990
Start Page
847
End Page
853

Differentiation of radiation fibrosis from recurrent neoplasia: a role for 31P MR spectroscopy?

Authors
Charles, HC; Baker, ME; Hathorn, JW; Sostman, D
MLA Citation
Charles, HC, Baker, ME, Hathorn, JW, and Sostman, D. "Differentiation of radiation fibrosis from recurrent neoplasia: a role for 31P MR spectroscopy?." AJR Am J Roentgenol 154.1 (January 1990): 67-68.
PMID
2104728
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
154
Issue
1
Publish Date
1990
Start Page
67
End Page
68
DOI
10.2214/ajr.154.1.2104728

Truncated sinc slice excitation for 31P spectroscopic imaging.

The shortest possible delay (Td) between slice selection and data acquisition is important for producing high quality 31P spectra. In single slice multivoxel spectroscopic imaging, conventional excitation using sinc-shaped rf pulses within typical gradient limitations can have values of Td that lead to significant spectral distortion and loss of signal. Truncated sinc excitation, which ends the excitation close to the center of the main rf lobe has been suggested for MR angiographic applications to produce short values of Td. In this work, the slice profiles, spectral signal-to-noise ratio (SNR) and spectral distortions are compared using the minimum delay achievable on a commercial MRI system for conventional 'sinc' rf excitation and truncated sinc excitation. Slice profiles are calculated using the Bloch equations and measured with a phantom. SNR and spectral distortions are evaluated from whole slice spectra on a human volunteer. On an MRI system with 1 G/cm gradients (0.5 msec risetime), for a 2.5-cm slice at 31P frequencies, conventional excitation can be adjusted to achieve Td = 2.5 msec while truncated sinc excitation yields Td = 1.5 msec. The truncated sinc excitation's shorter value of Td leads to much smaller spectral distortions, but its slice profile has "dispersive tails" which increase as more of the rf is truncated. Slice profile corrected SNR for the beta-ATP peak of 31P on a human volunteer is equivalent for both sequences while, qualitatively, in the PDE region the truncated sinc approach has improved SNR.

Authors
MacFall, JR; Charles, HC; Prost, R
MLA Citation
MacFall, JR, Charles, HC, and Prost, R. "Truncated sinc slice excitation for 31P spectroscopic imaging." Magn Reson Imaging 8.5 (1990): 619-624.
PMID
2082133
Source
pubmed
Published In
Magnetic Resonance Imaging
Volume
8
Issue
5
Publish Date
1990
Start Page
619
End Page
624

Soft-tissue sarcomas: MR imaging and MR spectroscopy for prognosis and therapy monitoring: Work in progress

The authors studied the usefulness of hydrogen-1 T2 measurements and phosphorus-31 magnetic resonance (MR) spectroscopy as indicators of prognosis and monitors of response to therapy in a group of patients with soft-tissue sarcomas. All eight patients were treated with combined local hyperthermia and fractionated radiation therapy, followed by surgical resection of the tumor. Each patient underwent T2 measurements and five patients underwent MR spectroscopy (phase encoded in one dimension) before treatment, after the first hyperthermia treatment, at the end of the therapy course, and just before surgery. Catheter thermometry was performed at each hyperthermia treatment. The T2 and MR spectroscopic variables were compared with thermometric data and the histologic findings from the complete surgical specimen. Changes in T2 correlated with histologic grade of tumor and thermometric data. The pretherapy tumor pH correlated positively, and changes during therapy in pH, ratio of phosphocreatine to inorganic phosphate (Pi), ratio of nucleoside triphosphate to Pi, and the phosphomonoester signal-to-noise ratio correlated negatively, with the percentage of tumor necrosis on the surgical specimen. These preliminary data suggest MR imaging and MR spectroscopy may be useful in the evaluation of such patients before and during therapy.

Authors
Dewhirst, MW; Sostman, HD; Leopold, KA; Charles, HC; Moore, D; Burn, RA; Tucker, JA; Harrelson, JM; Oleson, JR
MLA Citation
Dewhirst, MW, Sostman, HD, Leopold, KA, Charles, HC, Moore, D, Burn, RA, Tucker, JA, Harrelson, JM, and Oleson, JR. "Soft-tissue sarcomas: MR imaging and MR spectroscopy for prognosis and therapy monitoring: Work in progress." Radiology 174.3 (1990): 847-853.
Source
scival
Published In
Radiology
Volume
174
Issue
3
Publish Date
1990
Start Page
847
End Page
853

Chemical shift imaging of atherosclerosis at 7.0 Tesla.

Chemical shift imaging (CSI) was performed on cadaveric atherosclerotic fibrous plaques, periaortic adipose tissue, and cholesterol standards using a 7.0 Tesla horizontal bore prototype imaging spectrometer. Proton spectroscopy of intact tissue and deuterated chloroform extracted samples was done at the equivalent field strength of 7.0 Tesla on a vertical bore spectrometer, including studies of temperature dependence and T2 relaxation measurements. Spectra obtained using CSI on the imaging magnet were comparable with those from the conventional vertical spectrometer. Fibrous plaques and adipose tissue had unique spectral features, differing in the ratios of their water and various fat components. Chloroform extractions revealed a typical cholesteric ester spectrum for the fibrous plaque in contrast to the triglyceride spectrum of the adipose tissue. These two tissues also had different T2 relaxation measurements of their major fat resonances, with fibrous plaques having a short T2 compared to adipose tissue (15.9 milliseconds vs. 46.2 milliseconds). Temperature dependence studies showed that spectral signal intensity of the fat resonance of the fibrous plaque increased while linewidth decreased with increasing temperature from 24 degrees C to 37 degrees C. Atherosclerotic lesions may be studied at 7.0 Tesla, and NMR parameters defined in the present study may be used for further studies at other magnetic field strengths.

Authors
Maynor, CH; Charles, HC; Herfkens, RJ; Suddarth, SA; Johnson, GA
MLA Citation
Maynor, CH, Charles, HC, Herfkens, RJ, Suddarth, SA, and Johnson, GA. "Chemical shift imaging of atherosclerosis at 7.0 Tesla." Invest Radiol 24.1 (January 1989): 52-60.
PMID
2917823
Source
pubmed
Published In
Investigative Radiology
Volume
24
Issue
1
Publish Date
1989
Start Page
52
End Page
60

Cardiac applications of MR spectroscopy and spectroscopic imaging

Authors
Charles, HC
MLA Citation
Charles, HC. "Cardiac applications of MR spectroscopy and spectroscopic imaging." CardioVascular and Interventional Radiology 12.4 (1989): 215-216.
Source
scival
Published In
CardioVascular and Interventional Radiology
Volume
12
Issue
4
Publish Date
1989
Start Page
215
End Page
216

A COMPARISON OF SLICE SELECTION-STRATEGIES FOR P-31 SPECTROSCOPIC IMAGING

Authors
MACFALL, J; PROST, RA; KARFIAS, C; CHARLES, HC
MLA Citation
MACFALL, J, PROST, RA, KARFIAS, C, and CHARLES, HC. "A COMPARISON OF SLICE SELECTION-STRATEGIES FOR P-31 SPECTROSCOPIC IMAGING." AMERICAN JOURNAL OF NEURORADIOLOGY 10.4 (1989): 893-893.
Source
wos-lite
Published In
American Journal of Neuroradiology
Volume
10
Issue
4
Publish Date
1989
Start Page
893
End Page
893

INTEGRATION OF MRS AND MR FOR EVALUATION OF NEOPLASTIC DISEASE IN THE BRAIN

Authors
BOYKO, OB; PROST, RW; SCHOLD, SC; KARFIAS, C; CHARLES, HC
MLA Citation
BOYKO, OB, PROST, RW, SCHOLD, SC, KARFIAS, C, and CHARLES, HC. "INTEGRATION OF MRS AND MR FOR EVALUATION OF NEOPLASTIC DISEASE IN THE BRAIN." AMERICAN JOURNAL OF NEURORADIOLOGY 10.4 (1989): 893-893.
Source
wos-lite
Published In
American Journal of Neuroradiology
Volume
10
Issue
4
Publish Date
1989
Start Page
893
End Page
893

Integrated MR imaging and spectroscopy with chemical shift imaging of P-31 at 1.5 T: initial clinical experience.

A section-selective three-dimensional phosphorus-31 chemical shift imaging (CSI) experiment was evaluated as the spatial localization method for spectroscopy in an integrated clinical magnetic resonance (MR) imaging and spectroscopy examination. The results of a CSI experiment can be displayed as either spectra related to specific voxels or "metabolite maps," in which the relative concentration of a given metabolite is displayed as an overlay of the MR image. This method was applied to the study of a soft-tissue mass and to a meningioma. The total imaging time in each case was 17 minutes with a voxel size of 27 cm3 in the extremity and 64 cm3 in the brain. The total time to set up this part of the study was about 10 minutes. No additional shimming was necessary when the center of the field of view selected for the CSI experiment was located at or near isocenter. The promising results obtained with this approach make the CSI method an attractive choice of spatial localization method.

Authors
Lenkinski, RE; Holland, GA; Allman, T; Vogele, K; Kressel, HY; Grossman, RI; Charles, HC; Engeseth, HR; Flamig, D; MacFall, JR
MLA Citation
Lenkinski, RE, Holland, GA, Allman, T, Vogele, K, Kressel, HY, Grossman, RI, Charles, HC, Engeseth, HR, Flamig, D, and MacFall, JR. "Integrated MR imaging and spectroscopy with chemical shift imaging of P-31 at 1.5 T: initial clinical experience." Radiology 169.1 (October 1988): 201-206.
PMID
3420258
Source
pubmed
Published In
Radiology
Volume
169
Issue
1
Publish Date
1988
Start Page
201
End Page
206
DOI
10.1148/radiology.169.1.3420258

INVITRO CHEMICAL-SHIFT IMAGING OF ATHEROSCLEROSIS AT 7.0-TESLA

Authors
MAYNOR, CH; CHARLES, HC; HERFKENS, RJ; SUDDARTH, SA; JOHNSON, GA
MLA Citation
MAYNOR, CH, CHARLES, HC, HERFKENS, RJ, SUDDARTH, SA, and JOHNSON, GA. "INVITRO CHEMICAL-SHIFT IMAGING OF ATHEROSCLEROSIS AT 7.0-TESLA." INVESTIGATIVE RADIOLOGY 23.9 (September 1988): S3-S3.
Source
wos-lite
Published In
Investigative Radiology
Volume
23
Issue
9
Publish Date
1988
Start Page
S3
End Page
S3

Human in vivo phosphate metabolite imaging with 31P NMR.

Phosphorus (31P) spectroscopic images showing the distribution of high-energy phosphate metabolites in the human brain have been obtained at 1.5 T in scan times of 8.5 to 34 min at 27 and 64 cm3 spatial resolution using pulsed phase-encoding gradient magnetic fields and three-dimensional Fourier transform (3DFT) techniques. Data were acquired as free induction decays with a quadrature volume NMR detection coil of a truncated geometry designed to optimize the signal-to-noise ratio on the coil axis on the assumption that the sample noise represents the dominant noise source, and self-shielded magnetic field gradient coils to minimize eddy-current effects. The images permit comparison of metabolic data acquired simultaneously from different locations in the brain, as well as metabolite quantification by inclusion of a vial containing a standard of known 31P concentration in the image array. Values for the NMR visible adenosine triphosphate in three individuals were about 3 mM of tissue. The ratio of NMR detectable phosphocreatine to ATP in brain was 1.15 +/- 0.17 SD in these experiments. Potential sources of random and systematic error in these and other 31P measurements are identified.

Authors
Bottomley, PA; Charles, HC; Roemer, PB; Flamig, D; Engeseth, H; Edelstein, WA; Mueller, OM
MLA Citation
Bottomley, PA, Charles, HC, Roemer, PB, Flamig, D, Engeseth, H, Edelstein, WA, and Mueller, OM. "Human in vivo phosphate metabolite imaging with 31P NMR." Magn Reson Med 7.3 (July 1988): 319-336.
PMID
3205148
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
7
Issue
3
Publish Date
1988
Start Page
319
End Page
336

A simple method for processing NMR spectra in which acquisition is delayed: applications to in vivo localized 31P NMR spectra acquired using the DRESS technique.

It is a requirement of many localized NMR spectroscopy experiments, such as DRESS, that collection of the free induction decay be delayed a significant time after the middle of the last pulse. This leads to distortion of the spectra and seriously impedes the retrieval of quantitative information from these spectra. A technique is described in which a correction function is derived from the convoluted spectrum and is used to produce a spectrum with much reduced distortion from which quantitative information may easily be obtained by conventional techniques.

Authors
Allman, T; Holland, GA; Lenkinski, RE; Charles, HC
MLA Citation
Allman, T, Holland, GA, Lenkinski, RE, and Charles, HC. "A simple method for processing NMR spectra in which acquisition is delayed: applications to in vivo localized 31P NMR spectra acquired using the DRESS technique." Magn Reson Med 7.1 (May 1988): 88-94.
PMID
3386525
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
7
Issue
1
Publish Date
1988
Start Page
88
End Page
94

Internal trans-pars plana filtering procedure in humans.

Two patients (two eyes) with end-stage, medically uncontrollable glaucoma underwent transvitreal pars plana filtering procedures with a contact Nd:YAG laser with a sapphire probe. Intraocular pressure was being maintained without medication four months after surgery, with persistence of a diffuse filtering bleb.

Authors
Peyman, GA; Charles, HC; Alghadyan, A
MLA Citation
Peyman, GA, Charles, HC, and Alghadyan, A. "Internal trans-pars plana filtering procedure in humans." Int Ophthalmol 11.3 (January 1988): 159-162.
PMID
3417388
Source
pubmed
Published In
International Ophthalmology
Volume
11
Issue
3
Publish Date
1988
Start Page
159
End Page
162

Evaluation of choroidal neovascular membranes by Octopus perimetry.

A Sargon user-defined Octopus program was devised to quantitate central visual field changes following laser photocoagulation for choroidal neovascular membranes. The program was found to be reliable in testing the nine patients studied. All patients had areas of improved and areas of reduced sensitivity. The areas of reduced sensitivity were larger than the areas of improved sensitivity (P less than 0.05), with a net negative change in sensitivity found in all cases. However, the improved areas tended to be closer to fixation than the worsened areas. Quantitative static perimetry can be applied to the study of choroidal neovascular membranes. It is an important visual parameter that should be evaluated in future studies of these membranes, especially with regard to wavelength efficacy in photocoagulation therapy.

Authors
Nichols, PF; Charles, HC; Read, JS; Goldberg, MF
MLA Citation
Nichols, PF, Charles, HC, Read, JS, and Goldberg, MF. "Evaluation of choroidal neovascular membranes by Octopus perimetry." Retina 8.1 (1988): 24-29.
PMID
2457245
Source
pubmed
Published In
Retina
Volume
8
Issue
1
Publish Date
1988
Start Page
24
End Page
29

Intravitreal liposome-encapsulated drugs: a preliminary human report.

Intravitreal liposome-encapsulated antibiotics and antiviral drugs were used in patients with acute toxoplasmosis retinochoroiditis, presumed propionibacterium acne endophthalmitis after cataract surgery, and presumed cytomegalovirus retinitis associated with AIDS. A single intravitreal dose was effective in the treatment of all the conditions. Intravitreal liposomes may prove to be an advantageous drug delivery system for the treatment of chronic intraocular inflammatory disorders.

Authors
Peyman, GA; Charles, HC; Liu, KR; Khoobehi, B; Niesman, M
MLA Citation
Peyman, GA, Charles, HC, Liu, KR, Khoobehi, B, and Niesman, M. "Intravitreal liposome-encapsulated drugs: a preliminary human report." Int Ophthalmol 12.3 (1988): 175-182.
PMID
3265937
Source
pubmed
Published In
International Ophthalmology
Volume
12
Issue
3
Publish Date
1988
Start Page
175
End Page
182

Quantification of macular ischaemia in sickle cell retinopathy.

Macular ischaemia has a central role in the pathophysiology and prognosis of retinal macular disease. We attempted to quantitate two of its major components as follows: vascular nonperfusion, by measuring the foveal avascular zone (FAZ), using fluorescein angiography; and functional damage, using automated perimetry of the central 30 degrees. Sickle cell disease was chosen for study because it was considered a prototype for a purely ischaemic retinopathy without an exudative component. We found that the FAZ measurement was reproducible and that the patients with maculopathy had statistically larger FAZs than the normal controls (p = 0.016, Wilcoxon rank sum test). In addition, scotomas measured by visual field perimetry were significantly larger in the sickle cell patients with maculopathy than in those without maculopathy. Our results showed that angiography and perimetry of the central 30 degrees were more sensitive tests for the detection of ischaemic macular disease than visual acuity and that macular ischaemia could be quantified by their use.

Authors
Lee, CM; Charles, HC; Smith, RT; Peachey, NS; Cunha-Vaz, JG; Goldberg, MF
MLA Citation
Lee, CM, Charles, HC, Smith, RT, Peachey, NS, Cunha-Vaz, JG, and Goldberg, MF. "Quantification of macular ischaemia in sickle cell retinopathy." Br J Ophthalmol 71.7 (July 1987): 540-545.
PMID
3651368
Source
pubmed
Published In
British Journal of Ophthalmology
Volume
71
Issue
7
Publish Date
1987
Start Page
540
End Page
545

Electroretinographic findings in sickle cell retinopathy.

We obtained electroretinograms (ERGs) from normal subjects and from patients with sickle cell disease. The ERG components (a-wave, b-wave, and oscillatory potentials) obtained from normal subjects and patients without peripheral retinal neovascularization did not differ in either amplitude or implicit time. However, ERG components obtained from patients with peripheral retinal neovascularization were reduced in amplitude compared with those obtained from normal subjects or patients without neovascularization. The reduced a-wave, b-wave, and oscillatory potential amplitudes may have been due to photoreceptor dysfunction secondary to choroidal ischemia or possibly increased oxygen demands by the inner retina. Ischemia of the inner retina may also have contributed to the altered b-wave and oscillatory potentials. These results suggest that ERG provides a means of assessing the consequence of peripheral retinal ischemia to retinal cell function and could be of value in monitoring patients with sickle cell disease for the development of clinically significant peripheral retinal neovascularization.

Authors
Peachey, NS; Charles, HC; Lee, CM; Fishman, GA; Cunha-Vaz, JG; Smith, RT
MLA Citation
Peachey, NS, Charles, HC, Lee, CM, Fishman, GA, Cunha-Vaz, JG, and Smith, RT. "Electroretinographic findings in sickle cell retinopathy." Arch Ophthalmol 105.7 (July 1987): 934-938.
PMID
2440419
Source
pubmed
Published In
Archives of Ophthalmology
Volume
105
Issue
7
Publish Date
1987
Start Page
934
End Page
938

Quantification of diabetic macular edema.

In a cross-sectional study, 34 diabetic patients with clinically significant macular edema underwent visual acuity testing, stereo fundus photography (graded for retinal thickening and hard exudates), fluorescein angiography (evaluated for macular leakage and the outline of the foveal avascular zone [FAZ]), and vitreous fluorophotometry (whereby posterior penetration ratios were calculated). This last ratio provided the highest single correlation with visual acuity; next highest were patient age and FAZ grading. Multivariate regression confirmed that these three variables together best predicted visual acuity. Lesser correlations with acuity were obtained with angiographic leakage and fundus photography grading. Cross-correlations among all gradings showed that indicators of breakdown of the blood-retinal barrier, ie, fluorophotometry, angiographic leakage, and retinal thickening, were significantly correlated with each other, whereas FAZ grading was independent of all these factors and correlated only with acuity. By performing vitreous fluorophotometry and fluorescein angiography, it is possible to quantitate two major components of diabetic maculopathy: breakdown of the blood-retinal barrier and macular ischemia, both of which are highly correlated with visual acuity.

Authors
Smith, RT; Lee, CM; Charles, HC; Farber, M; Cunha-Vaz, JG
MLA Citation
Smith, RT, Lee, CM, Charles, HC, Farber, M, and Cunha-Vaz, JG. "Quantification of diabetic macular edema." Arch Ophthalmol 105.2 (February 1987): 218-222.
PMID
3813953
Source
pubmed
Published In
Archives of Ophthalmology
Volume
105
Issue
2
Publish Date
1987
Start Page
218
End Page
222

A clinicopathologic study of dye laser photocoagulation on primate retina.

Chorioretinal lesions produced by dye laser photocoagulation were examined on normal monkey retinas, using angiographic and histopathologic techniques. Retinal burns produced by green (514 nm), yellow (577 nm), orange (600 nm), and red (630 nm) laser lights were placed in the posterior pole between the fovea and the major vascular arcades. When examined histopathologically 24 hours after treatment, greater damage to the inner retina and deep choroid was noted with the red laser light than with the green, yellow and orange laser lights. These differences were not detectable 31 days after treatment. There were no appreciable acute differences among the lesions caused by green, yellow and orange irradiation. Laser light at four wavelengths of the orange spectrum (590, 595, 600, and 605 nm) produced comparable chorioretinal destruction in the juxtafoveal zone when examined 24 hours and 31 days after treatment. Retinal arterioles and venules treated with yellow (577 nm) and orange (600 nm) laser light demonstrated endothelial and pericytic cell damage. Changes in the outer retina, pigment epithelium, and choriocapillaris were also present beneath the photocoagulated vessels.

Authors
Borges, JM; Charles, HC; Lee, CM; Smith, RT; Cunha-Vaz, JG; Goldberg, MF; Tso, MO
MLA Citation
Borges, JM, Charles, HC, Lee, CM, Smith, RT, Cunha-Vaz, JG, Goldberg, MF, and Tso, MO. "A clinicopathologic study of dye laser photocoagulation on primate retina." Retina 7.1 (1987): 46-57.
PMID
3602607
Source
pubmed
Published In
Retina
Volume
7
Issue
1
Publish Date
1987
Start Page
46
End Page
57

Reproducibility of relaxation and spin-density parameters in phantoms and the human brain measured by MR imaging at 1.5 T.

The reproducibility of T1, T2, and proton density, measured in phantoms and the human brain was evaluated by proton imaging techniques. The sequence used to derive T1 and density values was a multiple-saturation recovery which consists of four pairs of 90 degrees pulses, followed by a 180 degrees phase reversal pulse, generating four T1-weighted images. T2 was derived from a multiple-echo sequence, generating four T2-weighted images. The data were analyzed by fitting the pixel intensities to the respective equations by means of nonlinear multiparameter least-squares analysis. Short-term reproducibility between four consecutive scans was evaluated to be 1-4% depending on location with a phantom covering the entire span of physiologic T1 and T2 values. A second phantom containing a series of identical samples served to study the dependence of the apparent T1 and T2 on position, both radially and axially, with respect to magnet isocenter. Reproducibility across the field of view was found to be better than 7% (T1 and T2). This phantom was further used to evaluate effects of long-term reproducibility, which at each location varied from 5-14% (T1) and 2-10% (T2). Finally, interinstrument reproducibility, tested by means of the same protocol on three different instruments, all operating at the same magnetic field and using largely identical hardware for each location, was found to be 1-14% (T1) and 2-10% (T2). The positional dependence of the apparent relaxation times appears to be systematic and may be due to variations in the effective field, caused by magnet and rf inhomogeneity. Finally, brain tissue relaxation and spin-density data were determined using the same protocol in 37 scans performed on 27 normal volunteers. The tissues analyzed were putamen, thalamus, caudate nucleus, centrum semiovale, internal capsule, and corpus callosum. Excellent accordance was further obtained between left and right hemispheres.

Authors
Breger, RK; Wehrli, FW; Charles, HC; MacFall, JR; Haughton, VM
MLA Citation
Breger, RK, Wehrli, FW, Charles, HC, MacFall, JR, and Haughton, VM. "Reproducibility of relaxation and spin-density parameters in phantoms and the human brain measured by MR imaging at 1.5 T." Magn Reson Med 3.5 (October 1986): 649-662.
PMID
3784884
Source
pubmed
Published In
Magnetic Resonance in Medicine
Volume
3
Issue
5
Publish Date
1986
Start Page
649
End Page
662

Respiratory effects in two-dimensional Fourier transform MR imaging

Respiratory and other regular motions during two-dimensional Fourier transform magnetic resonance imaging procedure image artifacts consisting of local blurring and more or less regularly spaced 'ghost' images propagating along the direction of the phase-encoding magnetic field gradient. The patterns of these ghost artifacts can be understood in terms of the technique of image production and basic properties of the discrete Fourier transform. This understanding permits, without respiratory gating, production of images of improved quality in body regions in which there is significant respiratory motion. In particular, the ghosts can be maximally separated from the primary image by choosing intervals between phase-encoding gradient pulse increments that are equal to one-half the respiratory period; they can be minimally separated by choosing an intergval equal to the respiratory period. Increasing the number of signal averages between each phase-encoding increment decreases the intensity of the ghosts.

Authors
Axel, L; Summers, RM; Kressel, HY; Charles, C
MLA Citation
Axel, L, Summers, RM, Kressel, HY, and Charles, C. "Respiratory effects in two-dimensional Fourier transform MR imaging." Radiology 160.3 (1986): 795-801.
PMID
3737920
Source
scival
Published In
Radiology
Volume
160
Issue
3
Publish Date
1986
Start Page
795
End Page
801

Quantification of contrast in clinical MR brain imaging at high magnetic field.

The relative contrast between two tissues in a magnetic resonance (MR) image is shown to be quantifiable for any combination of pulse timing parameters, provided the intrinsic parameters are known. Based on multiple inversion-recovery and spin echo images, a region-of-interest T1, T2 and density analysis was conducted at 1.4T in selected patients with diagnosed neuropathology for various brain tissues. The resulting tissue parameters subsequently served to calculate the contrast-to-noise (C/N) ratio for typical tissue interfaces as a function of the operator-variable pulse timing parameters and the data were compared with the images. Although such calculations may be useful as a protocol selection aid, it is obvious that an optimized pulse protocol can only be established for a single tissue interface. The data also reveal that a T2-discriminating pulse sequence like Carr-Purcell-Meiboom-Gill with long repetition time, generally advocated as clinically most effective, may not always be ideal.

Authors
Wehrli, FW; Breger, RK; MacFall, JR; Daniels, DL; Haughton, VM; Charles, HC; Williams, AL
MLA Citation
Wehrli, FW, Breger, RK, MacFall, JR, Daniels, DL, Haughton, VM, Charles, HC, and Williams, AL. "Quantification of contrast in clinical MR brain imaging at high magnetic field." Invest Radiol 20.4 (July 1985): 360-369.
PMID
4044176
Source
pubmed
Published In
Investigative Radiology
Volume
20
Issue
4
Publish Date
1985
Start Page
360
End Page
369

MR measurement of normal and pathologic brainstem diameters.

The dimensions of the brainstem were measured on magnetic resonance (MR) images to provide criteria for detecting brainstem enlargement. Twenty-eight normal adult subjects had MR imaging with sagittal partial-saturation and spin-echo sequences. Four patients with brainstem gliomas and three with cerebellar atrophy were also studied. Five measurements were made: (A) the distance between the interpeduncular fissure and the aqueduct, (B) the distance from the anterior surface of the cerebral peduncles to the aqueduct, (C) the distance between the anterior surface of the pons midway between the mesencephalon and medulla to the fourth ventricular floor, (D) the shortest anteroposterior diameter of the medulla at the pontomedullary junction, and (E) the shortest anteroposterior diameter of the medulla at the medullospinal junction. Pontine diameter could be measured more reproducibly and accurately than mesencephalic or medullary diameters. In four patients with glioma, one or more of the measured diameters were more than 2 SDs above the average in normal volunteers, and abnormally small measurements were found in the patients with atrophy.

Authors
Koehler, PR; Haughton, VM; Daniels, DL; Williams, AL; Yetkin, Z; Charles, HC; Shutts, D
MLA Citation
Koehler, PR, Haughton, VM, Daniels, DL, Williams, AL, Yetkin, Z, Charles, HC, and Shutts, D. "MR measurement of normal and pathologic brainstem diameters." AJNR Am J Neuroradiol 6.3 (May 1985): 425-427.
PMID
3923800
Source
pubmed
Published In
American Journal of Neuroradiology
Volume
6
Issue
3
Publish Date
1985
Start Page
425
End Page
427

Slice-interleaved depth-resolved surface-coil spectroscopy (SLIT DRESS) for rapid 31P NMR in Vivo

Authors
Bottomley, PA; Smith, LS; Leue, WM; Charles, C
MLA Citation
Bottomley, PA, Smith, LS, Leue, WM, and Charles, C. "Slice-interleaved depth-resolved surface-coil spectroscopy (SLIT DRESS) for rapid 31P NMR in Vivo." Journal of Magnetic Resonance (1969) 64.2 (1985): 347-351.
Source
scival
Published In
Journal of Magnetic Resonance (1969)
Volume
64
Issue
2
Publish Date
1985
Start Page
347
End Page
351

Synthesis, biological activity, and structure--activity/toxicity relationships of a series of terphenyl analogues of hemicholinium-3 and acetyl-seco-hemicholinium-3. 3.

Authors
Domer, FR; Chihal, DM; Charles, HC; Koch, RC
MLA Citation
Domer, FR, Chihal, DM, Charles, HC, and Koch, RC. "Synthesis, biological activity, and structure--activity/toxicity relationships of a series of terphenyl analogues of hemicholinium-3 and acetyl-seco-hemicholinium-3. 3." J Med Chem 23.5 (May 1980): 541-545.
PMID
7381853
Source
pubmed
Published In
Journal of Medicinal Chemistry
Volume
23
Issue
5
Publish Date
1980
Start Page
541
End Page
545

Biological evaluation of some norphenyl analogs of hemicholinium No. 3 and acetyl-seco-hemicholinium No. 3.

Authors
Domer, FR; Charles, HC; Koch, RC; Chihal, DM
MLA Citation
Domer, FR, Charles, HC, Koch, RC, and Chihal, DM. "Biological evaluation of some norphenyl analogs of hemicholinium No. 3 and acetyl-seco-hemicholinium No. 3." Arch Int Pharmacodyn Ther 234.2 (August 1978): 221-228.
PMID
708149
Source
pubmed
Published In
Archives internationales de pharmacodynamie et de therapie
Volume
234
Issue
2
Publish Date
1978
Start Page
221
End Page
228

Involvement of the sympathetic nervous system in the urinary bladder internal sphincter and in penile erection in the anesthetized cat.

Male cats were anesthetized with pentobarbital. In one series of experiments a Foley catheter was placed suprapubically in the urinary bladder and physiologic saline, under a constant head of pressure, was allowed to flow at a constant rate through the bladder. Alpha-adrenergic stimulants such as ephedrine, norepinephrine, or methoxamine all caused a decrease or cessation in urinary flow. This effect was reversed by the alpha-adrenergic blocking agent, phentolamine. In addition, phentolamine administration caused penile erection. Erection also occurred after administration of the alpha-adrenergic blocking agent, phenoxybenzamine, or the beta2-adrenergic stimulants terbutaline or salbutamol. In each case the erection could be reversed, and usually terminated completely, by administration of the beta-adrenergic blocking agent, propranolol. Hypotension per se was not the required event to initiate erection because administration of acetylcholine, histamine, or prostaglandin E2 did not result in penile erection. In two of five experiments nitroprusside caused an erection. It was concluded that a predominance of beta2 activity in the penile vasculature is involved in erection.

Authors
Domer, FR; Wessler, G; Brown, RL; Charles, HC
MLA Citation
Domer, FR, Wessler, G, Brown, RL, and Charles, HC. "Involvement of the sympathetic nervous system in the urinary bladder internal sphincter and in penile erection in the anesthetized cat." Invest Urol 15.5 (March 1978): 404-407.
PMID
205522
Source
pubmed
Published In
Investigative Urology
Volume
15
Issue
5
Publish Date
1978
Start Page
404
End Page
407

Biological evaluation of some biphenyl analogs of acetyl-seco-hemicholinium No. 3.

The oxygen atoms in the esteratic moiety of acetyl-seco-hemicholinium No. 3 (AcHC-3) were replaced with carbon to form the ether, ketone and aliphatic analogs. Also, the thio and acetylthio-seco analogs of hemicholinium No. 3 (HC-3) were studied. When evaluated in the rabbit sciatic nerve-gastrocnemius muscular preparation all of the analogs caused neuromuscular blockades in two or three separate phases. The first phase of blockade caused by the ketone and thio analogs was rapid in onset and reversed by neostigmine. It was presumably competitive in type. The first phase of blockade caused by the ether and aliphatic analogs was increased by neostigmine and was concluded to be of the non-competitive type. All analogs caused a second phase of blockade that was reversed by choline and is typical of HC-3. A third blockade was found following the ether and ketone analogs. All of the analogs were more active as inhibitors of the true and pseudocholinesterases than was HC-3. All of the analogs were much less potent as inhibitors of acetylcholine synthesis than was AcHC-3. The implications of these findings are discussed.

Authors
Domer, FR; Charles, HC; Chihal, DM; Koch, RC
MLA Citation
Domer, FR, Charles, HC, Chihal, DM, and Koch, RC. "Biological evaluation of some biphenyl analogs of acetyl-seco-hemicholinium No. 3." Arch Int Pharmacodyn Ther 229.2 (October 1977): 276-286.
PMID
596980
Source
pubmed
Published In
Archives internationales de pharmacodynamie et de therapie
Volume
229
Issue
2
Publish Date
1977
Start Page
276
End Page
286

Biological evaluation of some terphenyl analogs of hemicholinium No. 3.

Authors
Domer, FR; Koch, RC; Charles, HC; Chihal, DM
MLA Citation
Domer, FR, Koch, RC, Charles, HC, and Chihal, DM. "Biological evaluation of some terphenyl analogs of hemicholinium No. 3." Arch Int Pharmacodyn Ther 229.2 (October 1977): 251-260.
PMID
304340
Source
pubmed
Published In
Archives internationales de pharmacodynamie et de therapie
Volume
229
Issue
2
Publish Date
1977
Start Page
251
End Page
260

Cardiovascular and neuromuscular effects of dimethyl sulfoxide in anesthetized rabbits.

In rabbits anesthetized with pentobarbital, the carotid arterial blood pressure and bilateral contractions of the gastrocnemius muscles due to electrical stimulation of the sciatic nerves were recorded. Intravenous administration of up to 1 ml of dimethyl sulfoxide/kg caused profound hypotension and eventually failure of neuromuscular transmission. Caution must be used in considering dimethyl sulfoxide as a solvent for drug administration.

Authors
Domer, FR; Chihal, DM; Charles, HC
MLA Citation
Domer, FR, Chihal, DM, and Charles, HC. "Cardiovascular and neuromuscular effects of dimethyl sulfoxide in anesthetized rabbits." J Pharm Sci 66.2 (February 1977): 269-270.
PMID
839427
Source
pubmed
Published In
Journal of Pharmaceutical Sciences
Volume
66
Issue
2
Publish Date
1977
Start Page
269
End Page
270

Effect of sulfur substitution for the noncarbonyl oxygen in hemicholinium-3 and acetyl-seco-hemicholinium-3. Synthesis, biological activity, and structure-toxicity relationships.

As a continuation of our efforts to develop and study inhibitors which act presynaptically on neuromuscular function, sulfur analogues of hemicholinium-3 (HC-3, 1) and acetyl-seco-hemicholinium-3 (AcHC-3, 3) were prepared. In each case sulfur is substituted for the noncarbonyl oxygen in HC-3 (1) and AcHC-3 (3). As expected on the basis of conformational differences between acetylcholine and acetylthiocholine both of the thio analogues are produced in the seco form and do not cyclize spontaneously or when subjected to aqueous, acidic conditions up to 100 degrees C. Both compounds are stable in aqueous pH 7.4 solutions at 37 degrees C and in slightly acidic D2O solutions for more than 24 h. While thio-seco-hemicholinium 3 (11) is stable in the presence of acetylcholinesterase and butyrylcholinesterase in H2O at pH 7.4, acetylthio-seco-hemicholinium-3 (12) reacts within seconds to form the hemiacetal form of thiohemicholinium-3 (16). Mouse toxicity studies (LD50) indicate that while 12 is approximately as toxic as HC-3 (1) and AcHC-3 (3), 11 is 226 times less toxic. As in the studies with 1 and 3, mice were protected from 11 by choline and slightly by neostigmine. It is of interest, however, that almost equal and intermediate protection against 12 was afforded by choline and neostigmine. Structure-toxicity relationships of 1,3,11, 12, and 16 are discussed.

Authors
Domer, FR; Chihal, DM; Charles, HC; Rege, AB
MLA Citation
Domer, FR, Chihal, DM, Charles, HC, and Rege, AB. "Effect of sulfur substitution for the noncarbonyl oxygen in hemicholinium-3 and acetyl-seco-hemicholinium-3. Synthesis, biological activity, and structure-toxicity relationships." J Med Chem 20.1 (January 1977): 59-62.
PMID
833827
Source
pubmed
Published In
Journal of Medicinal Chemistry
Volume
20
Issue
1
Publish Date
1977
Start Page
59
End Page
62

Synthesis and structure-toxicity relationships of three new stable analogues of acetyl-seco-hemicholinium-3.

In order to develop and study inhibitors of neuromuscular function which act presynaptically, three stable analogues of acetyl-seco-hemicholinum-3 (AcHC-3,2) were prepared. These analogues have 2-ethoxyethyltrimethylammonium, 4-oxopentyltrimethylammonium, and n-pentyltrimethylammonium moieties substituted for the 2-acetylethyltrimethylammonium (acetylcholine) moieties of AcHC-3 (2) to form the ether 2, ketone 4, and alkane 5 analoggues of AcHC-3 (2). Although AcHC-3 (2) has been shown to undergo deesterification rapidly in basic solutions and slowly at pH 7.4, it has been found to be stable in H2O or D2O under slightly acidic conditions. All of the analogues are stable for extended time under both slightly acidic conditions and at pH 7.4 in H2O or D3O. It has been found that 2 reacts with acetylcholinesterase and butyrylcholinesterase within seconds in H2O at pH7.4. However, deesterification of 2 with subsequent cyclization to the hemiacetal form of hemicholinium-3 (HC-3, 1) is prevented at pH 7.4, possibly by an irreversible binding of 2 to the enzyme. The analogues 3-5, however, do not react under identical conditions. Mouse toxicity studies (LD50) indicate that 2 is approximately as toxic as HC-3 (1), whereas 3, 4, and 5 are 14.2, 23.8, and 43.1 times less toxic, respectively. The toxic effects of 3-5, like 1 and 2, are antagonized by choline but not by neostigmine in mice. Structure-activity relationships of 2-5 are discussed.

Authors
Haarstad, VB; Domer, FR; Chihal, DM; Rege, AB; Charles, HC
MLA Citation
Haarstad, VB, Domer, FR, Chihal, DM, Rege, AB, and Charles, HC. "Synthesis and structure-toxicity relationships of three new stable analogues of acetyl-seco-hemicholinium-3." J Med Chem 19.6 (June 1976): 760-763.
PMID
950641
Source
pubmed
Published In
Journal of Medicinal Chemistry
Volume
19
Issue
6
Publish Date
1976
Start Page
760
End Page
763
Show More

Research Areas:

  • Activities of Daily Living
  • Adenine Nucleotides
  • Adenosine Triphosphate
  • Adipokines
  • Adipose Tissue
  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aging
  • Alleles
  • Alzheimer Disease
  • Analysis of Variance
  • Animals
  • Antineoplastic Combined Chemotherapy Protocols
  • Apolipoprotein E4
  • Apolipoproteins E
  • Arthrography
  • Aspartic Acid
  • Asthma
  • Atrophy
  • Attention Deficit Disorder with Hyperactivity
  • Autistic Disorder
  • Autopsy
  • Biological Markers
  • Blood Glucose
  • Body Mass Index
  • Body Temperature
  • Bone Malalignment
  • Bone Neoplasms
  • Brain
  • Brain Chemistry
  • Brain Diseases
  • Breast Neoplasms
  • Calibration
  • Cartilage
  • Cartilage, Articular
  • Cerebral Ventricles
  • Chemical Phenomena
  • Chemistry
  • Child
  • Child, Preschool
  • Cholinesterase Inhibitors
  • Chromatography, High Pressure Liquid
  • Clinical Trials, Phase III as Topic
  • Cognition
  • Cognition Disorders
  • Cohort Studies
  • Coloring Agents
  • Combined Modality Therapy
  • Contrast Media
  • Creatine
  • Cross-Sectional Studies
  • Cystic Fibrosis
  • Deoxyglucose
  • Depressive Disorder
  • Developmental Disabilities
  • Diabetic Retinopathy
  • Diagnosis, Computer-Assisted
  • Diagnosis, Differential
  • Diagnostic Imaging
  • Diffusion
  • Disease Models, Animal
  • Disease Progression
  • Disease-Free Survival
  • Dog Diseases
  • Dogs
  • Dose-Response Relationship, Radiation
  • Double-Blind Method
  • Drug Carriers
  • Drug Combinations
  • Echoencephalography
  • Edema
  • Electric Stimulation
  • Epidemiologic Methods
  • Equipment Design
  • Ethanolamines
  • Europe
  • Evaluation Studies as Topic
  • Exercise
  • Extracellular Space
  • Eye Diseases
  • False Negative Reactions
  • False Positive Reactions
  • Feasibility Studies
  • Female
  • Femur
  • Fetal Diseases
  • Fibrosis
  • Fluorine Radioisotopes
  • Fluorocarbons
  • Fluorodeoxyglucose F18
  • Follow-Up Studies
  • Forelimb
  • Fractals
  • Gadolinium DTPA
  • Genetic Predisposition to Disease
  • Genotype
  • Glaucoma
  • Glucose
  • Glycine
  • Hemodynamics
  • Hippocampus
  • Humans
  • Hydrogen
  • Hydrogen-Ion Concentration
  • Hyperthermia, Induced
  • Image Enhancement
  • Image Interpretation, Computer-Assisted
  • Image Processing, Computer-Assisted
  • Imaging, Three-Dimensional
  • Indans
  • Infant
  • Inositol
  • International Cooperation
  • Internationality
  • Intracellular Fluid
  • Intraocular Pressure
  • Ischemia
  • Isotopes
  • Kaplan-Meier Estimate
  • Kidney
  • Kidney Transplantation
  • Knee Joint
  • Lactates
  • Lactic Acid
  • Laser Therapy
  • Leg
  • Lethal Dose 50
  • Light Coagulation
  • Liposomes
  • Longitudinal Studies
  • Lung
  • Lung Diseases
  • Magnetic Resonance Imaging
  • Magnetic Resonance Spectroscopy
  • Male
  • Mathematics
  • Memory
  • Memory Disorders
  • Microelectrodes
  • Microscopy, Electron
  • Middle Aged
  • Models, Biological
  • Molecular Conformation
  • Monitoring, Physiologic
  • Multicenter Studies as Topic
  • Muscle Neoplasms
  • Muscle, Skeletal
  • Muscles
  • Necrosis
  • Neoplasm Transplantation
  • Neoplasms
  • Neurology
  • Neuroma, Acoustic
  • Neurons
  • Neuropsychological Tests
  • Nootropic Agents
  • Obesity
  • Observer Variation
  • Odds Ratio
  • Organophosphates
  • Osteoarthritis, Knee
  • Osteophyte
  • Oxygen
  • Oxygen Consumption
  • Pain
  • Partial Pressure
  • Patella
  • Phantoms, Imaging
  • Phenylcarbamates
  • Phobic Disorders
  • Phosphates
  • Phosphocreatine
  • Phosphorus
  • Phosphorus Compounds
  • Phosphorus Isotopes
  • Phosphorus Radioisotopes
  • Phosphorylcholine
  • Photometry
  • Piperidines
  • Placebos
  • Polarography
  • Postoperative Complications
  • Postoperative Period
  • Posture
  • Predictive Value of Tests
  • Prenatal Diagnosis
  • Prognosis
  • Prospective Studies
  • Protons
  • Psychiatric Status Rating Scales
  • Psychiatry
  • Quality Assurance, Health Care
  • Quality Control
  • ROC Curve
  • Radiation Injuries
  • Radiation Oncology
  • Radiation Tolerance
  • Radiotherapy
  • Radiotherapy Dosage
  • Randomized Controlled Trials as Topic
  • Rats
  • Reference Standards
  • Reference Values
  • Regional Blood Flow
  • Reproducibility of Results
  • Research
  • Research Design
  • Respiratory Physiological Phenomena
  • Retina
  • Retinal Detachment
  • Retinal Diseases
  • Retinal Vessels
  • Risk Factors
  • Sarcoma
  • Sarcoma, Experimental
  • Seizures
  • Sensitivity and Specificity
  • Serine
  • Severity of Illness Index
  • Sex Characteristics
  • Signal Processing, Computer-Assisted
  • Soft Tissue Neoplasms
  • Solubility
  • Statistics as Topic
  • Structure-Activity Relationship
  • Survival Analysis
  • Technology
  • Technology Assessment, Biomedical
  • Temperature
  • Tetrahydrofolates
  • Thermodynamics
  • Thermography
  • Thermometers
  • Tibia
  • Time Factors
  • Tomography, Emission-Computed
  • Treatment Outcome
  • Tremor
  • Triglycerides
  • Tumor Cells, Cultured
  • Tumor Markers, Biological
  • Urinary Bladder
  • Visual Acuity
  • Visual Fields
  • Vitrectomy
  • Vomiting
  • Water
  • Weight-Bearing
  • Young Adult