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Marin, Daniele

Overview:

Liver Imaging
Dual Energy CT
CT Protocol Optimization
Dose Reduction Strategies for Abdominal CT Applications

Positions:

Associate Professor of Radiology

Radiology, Abdominal Imaging
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

M.D. 2003

M.D. — Sapienza University of Rome (Italy)

Grants:

Optimization of a Frequency-Based Fusion Technique for Improving the Image Quality on Low Energy Virtual Monochromatic Images from Dual Energy CT

Administered By
Radiology, Abdominal Imaging
AwardedBy
Radiological Society of North America
Role
Principal Investigator
Start Date
July 01, 2016
End Date
June 30, 2017

Decreased Variability for Robust Imaging-based Quantification of Tumor Heterogeneity

Administered By
Radiology, Abdominal Imaging
AwardedBy
Radiological Society of North America
Role
Principal Investigator
Start Date
July 01, 2015
End Date
June 30, 2017

Dual-Shot NCOM Power Contract Injector Study

Administered By
Radiology, Abdominal Imaging
AwardedBy
Nemoto Kyorindo Co., Ltd.
Role
Principal Investigator
Start Date
March 01, 2015
End Date
February 28, 2017

Howard Stern Research Grant

Administered By
Radiology, Abdominal Imaging
AwardedBy
Society of Abdominal Radiology
Role
Principal Investigator
Start Date
April 01, 2015
End Date
December 13, 2016
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Publications:

Imaging Advances for Urolithiasis.

The prevalence of urinary stones in the United States has been described as 1 in 11 persons reporting a history of stones. Imaging plays a crucial role in diagnosis, management and follow-up for these patients and imaging technology over the last 100 years has advanced as the disease prevalence has increased. Computed tomography (CT) remains the gold standard for imaging urolithiasis and changes in this technology, with the addition of multidetector CT and dual-energy CT, as well as the changes in utilization of CT, have decreased the radiation dose encountered by patients and allowed for improved stone detection. The use of Digital Tomography has been introduced for follow-up of recurrent stone formers offering the potential to lower radiation exposure over the course of a patient's life long treatment. However, there is still a demand for improved imaging techniques to detect smaller stones and stones in larger patients at lower radiation doses, as well as, the continued need for the judicious use of all imaging modalities for health care cost containment and patient safety.

Authors
Dale, JA; Gupta, RT; Marin, D; Lipkin, ME; Preminger, GM
MLA Citation
Dale, JA, Gupta, RT, Marin, D, Lipkin, ME, and Preminger, GM. "Imaging Advances for Urolithiasis." Journal of endourology (April 12, 2017).
PMID
28401803
Source
epmc
Published In
Journal of Endourology
Publish Date
2017
DOI
10.1089/end.2016.0695

Use of Preprocedural MDCT for Cardiac Implantable Electric Device Lead Extraction: Frequency of Findings That Change Management.

Five percent of cardiac implantable electric devices (CIEDs) are removed each year. Percutaneous extraction is preferred but can be complicated if the leads adhere to the vasculature or perforate. The goal of this study is to assess the frequency of findings on dedicated MDCT that alter preprocedural planning for percutaneous CIED extraction.One hundred patients with CIEDs who underwent MDCT before percutaneous lead extraction were analyzed. Major findings that could preclude percutaneous removal, including lead course and termination, were distinguished from moderately significant findings that could alter but not preclude percutaneous removal, including endofibrosis of leads to the vasculature, lead termination abnormalities, central vein stenosis, or thrombus. Incidental findings were characterized separately. Findings were correlated with preprocedural decisions, the extraction procedure performed, and procedural outcomes.Twenty-six women and 74 men with 125 right ventricular leads, 84 right atrial leads, and 26 coronary venous leads were evaluated. Major findings were present in 7% of patients, including six patients with lead perforation and one with a lead coursing outside a tricuspid annuloplasty ring. Moderately significant findings of endothelial fibrosis were found in 78% of patients. The central veins were narrowed or occluded in 42% of patients, and thrombus was present in 2% of patients. Thirty-six percent of patients had incidental findings, and 4% of patients had unexpected findings requiring immediate inpatient attention.MDCT performed before CIED lead extraction is able to identify major and moderately significant findings that can alter either percutaneous extraction or preprocedural planning. The use of dedicated preprocedural MDCT can help to stratify patient risk, guide decision making by the proceduralist, and identify non-catheter-related findings that affect patient management.

Authors
Ehieli, WL; Boll, DT; Marin, D; Lewis, R; Piccini, JP; Hurwitz, LM
MLA Citation
Ehieli, WL, Boll, DT, Marin, D, Lewis, R, Piccini, JP, and Hurwitz, LM. "Use of Preprocedural MDCT for Cardiac Implantable Electric Device Lead Extraction: Frequency of Findings That Change Management." AJR. American journal of roentgenology 208.4 (April 2017): 770-776.
PMID
28075624
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
208
Issue
4
Publish Date
2017
Start Page
770
End Page
776
DOI
10.2214/ajr.16.16897

Dual-energy CT workflow: multi-institutional consensus on standardization of abdominopelvic MDCT protocols.

To standardize workflow for dual-energy computed tomography (DECT) involving common abdominopelvic exam protocols.9 institutions (4 rsDECT, 1 dsDECT, 4 both) with 32 participants [average # years (range) in practice and DECT experience, 12.3 (1-35) and 4.6 (1-14), respectively] filled out a single survey (n = 9). A five-point agreement scale (0, 1, 2, 3, 4-contra-, not, mildly, moderately, strongly indicated, respectively) and utilization scale (0-not performing and shouldn't; 1-performing but not clinically useful; 2-performing but not sure if clinically useful; 3-not performing it but would like to; 4-performing and clinically useful) were used. Consensus was considered with a score of ≥2.5. Survey results were discussed over three separate live webinar sessions.5/9 (56%) institutions exclude large patients from DECT. 2 (40%) use weight, 2 (40%) use transverse dimension, and 1 (20%) uses both. 7/9 (78%) use 50 keV for low and 70 keV for medium monochromatic reconstructed images. DECT is indicated for dual liver [agreement score (AS) 3.78; utilization score (US) 3.22] and dual pancreas in the arterial phase (AS 3.78; US 3.11), mesenteric ischemia/gastrointestinal bleeding in both the arterial and venous phases (AS 2.89; US 2.79), RCC exams in the arterial phase (AS 3.33; US 2.78), and CT urography in the nephrographic phase (AS 3.11; US 2.89). DECT for renal stone and certain single-phase exams is indicated (AS 3.00).DECT is indicated during the arterial phase for multiphasic abdominal exams, nephrographic phase for CTU, and for certain single-phase and renal stone exams.

Authors
Patel, BN; Alexander, L; Allen, B; Berland, L; Borhani, A; Mileto, A; Moreno, C; Morgan, D; Sahani, D; Shuman, W; Tamm, E; Tublin, M; Yeh, B; Marin, D
MLA Citation
Patel, BN, Alexander, L, Allen, B, Berland, L, Borhani, A, Mileto, A, Moreno, C, Morgan, D, Sahani, D, Shuman, W, Tamm, E, Tublin, M, Yeh, B, and Marin, D. "Dual-energy CT workflow: multi-institutional consensus on standardization of abdominopelvic MDCT protocols." Abdominal radiology (New York) 42.3 (March 2017): 676-687.
PMID
27888303
Source
epmc
Published In
Abdominal radiology (New York)
Volume
42
Issue
3
Publish Date
2017
Start Page
676
End Page
687
DOI
10.1007/s00261-016-0966-6

Dual-Energy Computed Tomography in Genitourinary Imaging.

Reignited by innovations in scanner engineering and software design, dual-energy computed tomography (CT) has come back into the clinical radiology arena in the last decade. Possibilities for noninvasive in vivo characterization of genitourinary disease, especially for renal stones and renal masses, have become the pinnacle offerings of dual-energy CT for body imaging in clinical practice. This article renders a state-of-the-art review on clinical applications of dual-energy CT in genitourinary imaging.

Authors
Mileto, A; Marin, D
MLA Citation
Mileto, A, and Marin, D. "Dual-Energy Computed Tomography in Genitourinary Imaging." Radiologic clinics of North America 55.2 (March 2017): 373-391.
PMID
28126221
Source
epmc
Published In
Radiologic Clinics of North America
Volume
55
Issue
2
Publish Date
2017
Start Page
373
End Page
391
DOI
10.1016/j.rcl.2016.10.006

Use of a Noise Optimized Monoenergetic Algorithm for Patient-Size Independent Selection of an Optimal Energy Level During Dual-Energy CT of the Pancreas.

To investigate the impact of a second-generation noise-optimized monoenergetic algorithm on selection of the optimal energy level, image quality, and effect of patient body habitus for dual-energy multidetector computed tomography of the pancreas.Fifty-nine patients (38 men, 21 women) underwent dual-energy multidetector computed tomography (80/Sn140 kV) in the pancreatic parenchymal phase. Image data sets, at energy levels ranging from 40 to 80 keV (in 5-keV increments), were reconstructed using first-generation and second-generation noise-optimized monoenergetic algorithm. Noise, pancreatic contrast-to-noise ratio (CNRpancreas), and CNR with a noise constraint (CNRNC) were calculated and compared among the different reconstructed data sets. Qualitative assessment of image quality was performed by 3 readers.For all energy levels below 70 keV, noise was significantly lower (P ≤ 0.05) and CNRpancreas significantly higher (P < 0.001), with the second-generation monoenergetic algorithm. Furthermore, the second-generation algorithm was less susceptible to variability related to patient body habitus in the selection of the optimal energy level. The maximal CNRpancreas occurred at 40 keV in 98% (58 of 59) of patients with the second-generation monoenergetic algorithm. However, the CNRNC and readers' image quality scores showed that, even with a second-generation monoenergetic algorithm, higher reconstructed energy levels (60-65 keV) represented the optimal energy level.Second-generation noise-optimized monoenergetic algorithm can improve the image quality of lower-energy monoenergetic images of the pancreas, while decreasing the variability related to patient body habitus in selection of the optimal energy level.

Authors
Bellini, D; Gupta, S; Ramirez-Giraldo, JC; Fu, W; Stinnett, SS; Patel, B; Mileto, A; Marin, D
MLA Citation
Bellini, D, Gupta, S, Ramirez-Giraldo, JC, Fu, W, Stinnett, SS, Patel, B, Mileto, A, and Marin, D. "Use of a Noise Optimized Monoenergetic Algorithm for Patient-Size Independent Selection of an Optimal Energy Level During Dual-Energy CT of the Pancreas." Journal of computer assisted tomography 41.1 (January 2017): 39-47.
PMID
27560021
Source
epmc
Published In
Journal of Computer Assisted Tomography
Volume
41
Issue
1
Publish Date
2017
Start Page
39
End Page
47
DOI
10.1097/rct.0000000000000492

Imaging the renal lesion with dual-energy multidetector CT and multi-energy applications in clinical practice: what can it truly do for you?

Many fortuitously detected renal lesions are incompletely characterised at traditional MDCT imaging, thus posing daily challenges to radiologists and referring physicians. There is burgeoning evidence that dual-energy MDCT and multi-energy applications provide an added value over traditional MDCT imaging in renal lesion characterisation and throughput. This special report gives a vendor-neutral outlook on technical essentials, recommended protocols, high-yield clinical opportunities and reviews radiation dose aspects of dual-energy MDCT imaging and multi-energy applications in renal lesions. In addition to a guide on interpretative traps and emerging problems, we provide an update on new, potential imaging horizons.Dual-energy MDCT and multi-energy applications can facilitate the imaging interpretation and throughput of renal lesions. Conjointly with capitalisation on the benefits, familiarity with dual- and multi-energy data sets as well as continuous scrutiny of interpretative traps can be the keys to the successful implementation and enhanced clinical acceptance of this powerful technique in the imaging community. Continuous advances in hardware and computer interfaces are expected to pave the way for the further expansion of the application spectrum.• Optimal protocols must be adopted for leveraging dual-energy benefits in renal imaging. • Virtual monochromatic imaging can overcome renal cyst pseudoenhancement. • Iodine maps help to interpret renal lesions incompletely characterised at traditional MDCT. • Interpretative traps need to be weighed-up in dual-energy renal lesions imaging. • Technical advances are expanding the dual-energy applications spectrum for renal lesions imaging.

Authors
Mileto, A; Sofue, K; Marin, D
MLA Citation
Mileto, A, Sofue, K, and Marin, D. "Imaging the renal lesion with dual-energy multidetector CT and multi-energy applications in clinical practice: what can it truly do for you?." European radiology 26.10 (October 2016): 3677-3690.
PMID
26801162
Source
epmc
Published In
European Radiology
Volume
26
Issue
10
Publish Date
2016
Start Page
3677
End Page
3690
DOI
10.1007/s00330-015-4180-7

Adoption of Splenic Enhancement to Time and Trigger the Late Hepatic Arterial Phase During MDCT of the Liver: Proof of Concept and Clinical Feasibility.

The purpose of this study was to prospectively investigate the clinical feasibility of adopting splenic enhancement for timing and triggering the acquisition of late hepatic arterial phase images during multiphasic liver MDCT for assessment of hypervascular tumors.Forty-eight patients (33 men, 15 women; median age, 59 years; chronic liver disease, 23 patients; portal venous hypertension, 17 patients) with a total of 81 hypervascular liver tumors underwent liver MDCT by random assignment to one of two scanning protocols. Scanning delay for the late hepatic arterial phase was determined by assessment of time-to-peak splenic enhancement (splenic-triggering protocol) or aortic enhancement (aortic-triggering protocol). Acquisition timing, vascular attenuation, liver attenuation and homogeneity, signal-to-noise ratio, tumor-to-liver contrast, and tumor-to-liver contrast-to-noise ratio were compared. Two blinded independent observers used Likert scales to score timing adequacy (3-point scale), diagnostic confidence (5-point scale), and per lesion conspicuity (4-point scale) for hypervascular tumor detection.The splenic- and aortic-triggering protocols had significant differences in mean late hepatic arterial phase imaging timing (splenic, 36 ± 6 seconds; aortic, 32 ± 3 seconds; p = 0.010). Images obtained with the splenic-triggering protocol had significantly better observer-based judgment of adequacy (splenic, 2.04; aortic, 1.58; p = 0.002). Mean attenuation and signal-to-noise ratios from liver and portal vein were significantly higher with the splenic- than with the aortic-triggering protocol (p < 0.0001). The splenic-triggering protocol was associated with significant improvement in homogeneity of liver attenuation (p < 0.0001). Although the splenic-triggering protocol was associated with significantly higher lesion conspicuity than was the aortic-triggering protocol (p = 0.022), there was no significant difference in tumor detection rate.Our results provide a clinical foundation for and proof of principle that the adoption of splenic enhancement renders an optimal temporal window for late hepatic arterial phase imaging during MDCT of the liver for assessment of hypervascular tumors.

Authors
Mileto, A; Husarik, DB; Bellini, D; Marin, D; Reiner, CS; Nelson, RC
MLA Citation
Mileto, A, Husarik, DB, Bellini, D, Marin, D, Reiner, CS, and Nelson, RC. "Adoption of Splenic Enhancement to Time and Trigger the Late Hepatic Arterial Phase During MDCT of the Liver: Proof of Concept and Clinical Feasibility." AJR. American journal of roentgenology 207.2 (August 2016): 310-320.
PMID
27253268
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
207
Issue
2
Publish Date
2016
Start Page
310
End Page
320
DOI
10.2214/ajr.15.15808

Regional Mapping of Aortic Wall Stress by Using Deformable, Motion-coherent Modeling based on Electrocardiography-gated Multidetector CT Angiography: Feasibility Study.

Purpose To investigate the feasibility of deformable, motion-coherent modeling based on electrocardiography-gated multidetector computed tomographic (CT) angiography of the thoracic aorta and to evaluate whether quantifiable information on aortic wall stress as a function of patient-specific cardiovascular parameters can be gained. Materials and Methods For this institutional review board-approved, HIPAA-compliant study, thoracic electrocardiography-gated dual-source multidetector CT angiographic images were used from 250 prospectively enrolled patients (150 men, 100 women; mean age, 79 years). On reconstructed 50-phase CT angiographic images, aortic strain and deformation were determined at seven cardiac and aortic locations. One-way analysis of variance was used by assessing the magnitude for longitudinal and axial strain and axial deformation, as well as time-resolved peak and maxima count for longitudinal strain and axial deformation. Interdependencies between aortic strain and deformation with extracted hemodynamic parameters were evaluated. Results With increasing heart rates, there was a significant decrease in longitudinal strain (P = .009, R(2) = 0.95) and a decrease in the number of longitudinal strain peaks (P < .001, R(2) = 0.79); however, a significant increase in axial deformation (P < .001, R(2) = 0.31) and axial strain (P = .009, R(2) = 0.61) was observed. Increasing aortic blood velocity led to increased longitudinal strain (P = .018, R(2) = 0.42) and longitudinal strain peak counts (P = .011, R(2) = 0.48). Pronounced motion in the longitudinal direction limited motion in the axial plane (P < .019, R(2) = 0.29-0.31). Conclusion The results of this study render a clinical basis and provide proof of principle for the use of deformable, motion-coherent modeling to provide quantitative information on physiological motion of the aorta under various hemodynamic circumstances. (©) RSNA, 2016 Online supplemental material is available for this article.

Authors
Mileto, A; Heye, TJ; Makar, RA; Hurwitz, LM; Marin, D; Boll, DT
MLA Citation
Mileto, A, Heye, TJ, Makar, RA, Hurwitz, LM, Marin, D, and Boll, DT. "Regional Mapping of Aortic Wall Stress by Using Deformable, Motion-coherent Modeling based on Electrocardiography-gated Multidetector CT Angiography: Feasibility Study." Radiology 280.1 (July 2016): 230-236.
PMID
26780540
Source
epmc
Published In
Radiology
Volume
280
Issue
1
Publish Date
2016
Start Page
230
End Page
236
DOI
10.1148/radiol.2015151078

Effect of a Noise-Optimized Second-Generation Monoenergetic Algorithm on Image Noise and Conspicuity of Hypervascular Liver Tumors: An In Vitro and In Vivo Study.

The purpose of this study is to investigate whether the reduction in noise using a second-generation monoenergetic algorithm can improve the conspicuity of hypervascular liver tumors on dual-energy CT (DECT) images of the liver.An anthropomorphic liver phantom in three body sizes and iodine-containing inserts simulating hypervascular lesions was imaged with DECT and single-energy CT at various energy levels (80-140 kV). In addition, a retrospective clinical study was performed in 31 patients with 66 hypervascular liver tumors who underwent DECT during the late hepatic arterial phase. Datasets at energy levels ranging from 40 to 80 keV were reconstructed using first- and second-generation monoenergetic algorithms. Noise, tumor-to-liver contrast-to-noise ratio (CNR), and CNR with a noise constraint (CNRNC) set with a maximum noise increase of 50% were calculated and compared among the different reconstructed datasets.The maximum CNR for the second-generation monoenergetic algorithm, which was attained at 40 keV in both phantom and clinical datasets, was statistically significantly higher than the maximum CNR for the first-generation monoenergetic algorithm (p < 0.001) or single-energy CT acquisitions across a wide range of kilovoltage values. With the second-generation monoenergetic algorithm, the optimal CNRNC occurred at 55 keV, corresponding to lower energy levels compared with first-generation algorithm (predominantly at 70 keV). Patient body size did not substantially affect the selection of the optimal energy level to attain maximal CNR and CNRNC using the second-generation monoenergetic algorithm.A noise-optimized second-generation monoenergetic algorithm significantly improves the conspicuity of hypervascular liver tumors.

Authors
Marin, D; Ramirez-Giraldo, JC; Gupta, S; Fu, W; Stinnett, SS; Mileto, A; Bellini, D; Patel, B; Samei, E; Nelson, RC
MLA Citation
Marin, D, Ramirez-Giraldo, JC, Gupta, S, Fu, W, Stinnett, SS, Mileto, A, Bellini, D, Patel, B, Samei, E, and Nelson, RC. "Effect of a Noise-Optimized Second-Generation Monoenergetic Algorithm on Image Noise and Conspicuity of Hypervascular Liver Tumors: An In Vitro and In Vivo Study." AJR. American journal of roentgenology 206.6 (June 2016): 1222-1232.
PMID
27058192
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
206
Issue
6
Publish Date
2016
Start Page
1222
End Page
1232
DOI
10.2214/ajr.15.15512

Can combining triple-arterial phase acquisition with fluoroscopic triggering provide both optimal early and late hepatic arterial phase images during gadoxetic acid-enhanced MRI?

To determine whether triple-arterial phase acquisition with fluoroscopic triggering can provide both well-timed early and late hepatic arterial phase (HAP) images more frequently than when using a fixed-time delay during gadoxetic acid-enhanced magnetic resonance imaging (MRI).Written informed consent was obtained for this Institutional Review Board (IRB)-approved prospective, Health Insurance Portability and Accountability Act (HIPAA)-compliant study. Ninety patients underwent gadoxetic acid-enhanced MRI at 3T with a single-breath-hold triple-arterial phase acquisition using either a fixed-time delay (n = 45) or fluoroscopic triggering injection protocol (n = 45). Three radiologists, blinded to method of timing and other data, independently determined whether well-timed early or late HAP were obtained for each arterial phase image set and assessed for transient severe motion (TSM). Rates of successful HAP acquisitions and of TSM were compared between the two protocols using χ(2) or Fisher's exact test.The rate of successful acquisition of late HAP images was similar in the two groups (93% [42/45] for fixed-time delay vs. 98% [44/45] for fluoroscopic triggering, P = 0.62). There was a trend toward higher rates of successful acquisition of both early and late HAP images in the fluoroscopic triggering group (69% [31/45] vs. 49% [22/45], P = 0.05). TSM occurred in five patients (6% [5/90]) and at similar frequencies in the two groups (2% [1/45] vs. 9% [4/45], P = 0.36).Triple-arterial phase acquisition with fluoroscopic triggering tended to provide both well-timed early and late HAP images more frequently than when using a fixed-time delay during gadoxetic acid-enhanced MRI.

Authors
Sofue, K; Marin, D; Jaffe, TA; Nelson, RC; Bashir, MR
MLA Citation
Sofue, K, Marin, D, Jaffe, TA, Nelson, RC, and Bashir, MR. "Can combining triple-arterial phase acquisition with fluoroscopic triggering provide both optimal early and late hepatic arterial phase images during gadoxetic acid-enhanced MRI?." Journal of magnetic resonance imaging : JMRI 43.5 (May 2016): 1073-1081.
PMID
26469796
Source
epmc
Published In
Journal of Magnetic Resonance Imaging
Volume
43
Issue
5
Publish Date
2016
Start Page
1073
End Page
1081
DOI
10.1002/jmri.25079

Virtual Monochromatic Images from Dual-Energy Multidetector CT: Variance in CT Numbers from the Same Lesion between Single-Source Projection-based and Dual-Source Image-based Implementations.

To determine the variance in virtual monochromatic computed tomography (CT) numbers from the same lesion, comparing the two clinically available dual-energy multidetector CT hardware implementations (single-source projection-based and dual-source image-based), in a phantom-based simulated abdominal environment.This phantom-based study was exempt from institutional review board oversight. Polyethylene terephthalate spheres (15 and 18 mm) with two iodine-to-saline dilutions (0.8 and 1.2 mg of iodine per millilliter) were serially suspended in a cylindrical polypropylene bottle filled with diluted iodinated contrast material. The bottle was placed into a 36-cm-wide torso-shaped water phantom simulating the abdomen of a medium-sized patient. Dual-energy (80/140 kVp) and single-energy (100 and 120 kVp) scans were obtained with single-source and dual-source multidetector CT implementations. Virtual monochromatic images were reconstructed at energy levels of 40-140 keV (in 10-keV increments) in either the projection-space or image-space domain. A multivariate regression analysis approach was used to investigate the effect of energy level, lesion size, lesion iodine content, and implementation type on measured CT numbers.There were significant differences in the attenuation values measured in the simulated lesions with the single-source projection-based platform and the dual-source image-based implementation (P < .001 for all comparisons). The magnitude of these differences was greatest at lower monochromatic energy levels and at lower iodine concentrations (average difference at 40 keV: 25.7 HU; average difference at 140 keV: 7 HU). The monochromatic energy level and the lesion iodine concentration had a significant effect on the difference in the measured attenuation values between the two implementations, which indicates that the two imaging platforms respond differently to changes in investigated variables (P < .001 for all comparisons).There is a statistically significant variance in virtual monochromatic CT numbers from the same lesion examined with single-source projection-based and dual-source image-based implementations. The magnitude of the variance is a function of the selected energy level and the lesion iodine content.

Authors
Mileto, A; Barina, A; Marin, D; Stinnett, SS; Roy Choudhury, K; Wilson, JM; Nelson, RC
MLA Citation
Mileto, A, Barina, A, Marin, D, Stinnett, SS, Roy Choudhury, K, Wilson, JM, and Nelson, RC. "Virtual Monochromatic Images from Dual-Energy Multidetector CT: Variance in CT Numbers from the Same Lesion between Single-Source Projection-based and Dual-Source Image-based Implementations." Radiology 279.1 (April 2016): 269-277.
PMID
26536403
Source
epmc
Published In
Radiology
Volume
279
Issue
1
Publish Date
2016
Start Page
269
End Page
277
DOI
10.1148/radiol.2015150919

Application of a Novel CT-Based Iliac Artery Calcification Scoring System for Predicting Renal Transplant Outcomes.

The objective of our study was to assess whether the degree and distribution of iliac artery calcifications as determined by a CT-based calcium scoring system correlates with outcomes after renal transplant.A retrospective review of renal transplant recipients who underwent CT of the pelvis within 2 years before surgery yielded 131 patients: 75 men and 56 women with a mean age of 52 years. Three radiologists assigned a separate semiquantitative score for calcification length, circumferential involvement, and morphology for the common iliac arteries and for the external iliac arteries. The operative and clinical notes were reviewed to determine which iliac arterial segment was used for anastomosis, the complexity of the operation, and whether delayed graft function (DGF) occurred. Renal allograft survival and patient survival were calculated using the Kaplan-Meier technique.Excellent interobserver agreement was noted for each calcification score category. The common iliac arteries showed significantly higher average calcification scores than the external iliac arteries for all categories. Advanced age and diabetes mellitus were independently predictive of higher scores in each category, whereas hypertension, cigarette smoking, hyperlipidemia, and sex were not. Based on multivariate analysis, only the calcification morphology score of the arterial segment used for anastomosis was independently predictive of a higher rate of surgical complexity and of DGF. None of the scores was predictive of graft or patient survival. However, patients with CT evidence of iliac arterial calcification had a lower 1-year survival after transplant than those who did not (92% vs 98%, respectively; p = 0.05).Only the calcification morphology score of the arterial segment used for anastomosis was significantly predictive of surgical complexity and of DGF. Routine pretransplant CT for calcification scoring in patients of advanced age or those with diabetes mellitus may enable selection of the optimal artery for anastomosis to optimize outcomes.

Authors
Davis, B; Marin, D; Hurwitz, LM; Ronald, J; Ellis, MJ; Ravindra, KV; Collins, BH; Kim, CY
MLA Citation
Davis, B, Marin, D, Hurwitz, LM, Ronald, J, Ellis, MJ, Ravindra, KV, Collins, BH, and Kim, CY. "Application of a Novel CT-Based Iliac Artery Calcification Scoring System for Predicting Renal Transplant Outcomes." AJR. American journal of roentgenology 206.2 (February 2016): 436-441.
PMID
26797375
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
206
Issue
2
Publish Date
2016
Start Page
436
End Page
441
DOI
10.2214/ajr.15.14794

New Imaging in Gastrointestinal Tract.

Authors
Grassi, R; Pinto, A; Mannelli, L; Marin, D; Mazzei, MA
MLA Citation
Grassi, R, Pinto, A, Mannelli, L, Marin, D, and Mazzei, MA. "New Imaging in Gastrointestinal Tract." Gastroenterology research and practice 2016 (January 2016): 5785871-.
PMID
26966429
Source
epmc
Published In
Gastroenterology Research and Practice
Volume
2016
Publish Date
2016
Start Page
5785871
DOI
10.1155/2016/5785871

Dual-Energy Multidetector Computed Tomography With Iodine Quantification in the Evaluation of Portal Vein Thrombosis: Is It Possible to Discard the Unenhanced Phase?

Authors
Ascenti, G; Sofia, C; Silipigni, S; Vinci, S; Pergolizzi, S; Marin, D; Mileto, A; Mazziotti, S
MLA Citation
Ascenti, G, Sofia, C, Silipigni, S, Vinci, S, Pergolizzi, S, Marin, D, Mileto, A, and Mazziotti, S. "Dual-Energy Multidetector Computed Tomography With Iodine Quantification in the Evaluation of Portal Vein Thrombosis: Is It Possible to Discard the Unenhanced Phase?." Canadian Association of Radiologists journal = Journal l'Association canadienne des radiologistes 66.4 (November 2015): 348-355.
PMID
26277236
Source
epmc
Published In
Canadian Association of Radiologists Journal
Volume
66
Issue
4
Publish Date
2015
Start Page
348
End Page
355
DOI
10.1016/j.carj.2015.04.001

Effect of radiologists' experience with an adaptive statistical iterative reconstruction algorithm on detection of hypervascular liver lesions and perception of image quality.

To prospectively evaluate whether clinical experience with an adaptive statistical iterative reconstruction algorithm (ASiR) has an effect on radiologists' diagnostic performance and confidence for the diagnosis of hypervascular liver tumors, as well as on their subjective perception of image quality.Forty patients, having 65 hypervascular liver tumors, underwent contrast-enhanced MDCT during the hepatic arterial phase. Image datasets were reconstructed with filtered backprojection algorithm and ASiR (20%, 40%, 60%, and 80% blending). During two reading sessions, performed before and after a three-year period of clinical experience with ASiR, three readers assessed datasets for lesion detection, likelihood of malignancy, and image quality.For all reconstruction algorithms, there was no significant change in readers' diagnostic accuracy and sensitivity for the detection of liver lesions, between the two reading sessions. However, a 60% ASiR dataset yielded a significant improvement in specificity, lesion conspicuity, and confidence for lesion likelihood of malignancy during the second reading session (P < 0.0001). The 60% ASiR dataset resulted in significant improvement in readers' perception of image quality during the second reading session (P < 0.0001).Clinical experience using an ASiR algorithm may improve radiologists' diagnostic performance for the diagnosis of hypervascular liver tumors, as well as their perception of image quality.

Authors
Marin, D; Mileto, A; Gupta, RT; Ho, LM; Allen, BC; Choudhury, KR; Nelson, RC
MLA Citation
Marin, D, Mileto, A, Gupta, RT, Ho, LM, Allen, BC, Choudhury, KR, and Nelson, RC. "Effect of radiologists' experience with an adaptive statistical iterative reconstruction algorithm on detection of hypervascular liver lesions and perception of image quality." Abdominal imaging 40.7 (October 2015): 2850-2860.
PMID
25783958
Source
epmc
Published In
Abdominal Imaging
Volume
40
Issue
7
Publish Date
2015
Start Page
2850
End Page
2860
DOI
10.1007/s00261-015-0398-8

Diagnostic performance of imaging criteria for distinguishing autoimmune cholangiopathy from primary sclerosing cholangitis and bile duct malignancy.

To determine the diagnostic performance of imaging criteria for distinguishing Ig-G4-associated autoimmune cholangiopathy (IAC) from primary sclerosing cholangitis (PSC) and bile duct malignancy.A medical records search between January 2008 and October 2013 identified 10 patients (8 M, 2 F, mean age 61 years, range 34-82) with a clinical diagnosis of IAC. Fifteen cases of PSC (6 M, 9 F, mean age 50, range 22-65) and 15 cases of biliary malignancy (7 M, 8 F, mean age 65, range 48-84) were randomly selected for comparative analysis. Three abdominal radiologists independently reviewed MRI with MRCP (n = 32) or CT (n = 8) and ERCP (n = 8) for the following IAC imaging predictors: single-wall bile duct thickness >2.5 mm, continuous biliary involvement, gallbladder involvement, liver disease, peribiliary mass, or pancreatic and renal abnormalities. Each radiologist provided an imaging-based diagnosis (IAC, PSC, or cancer). Imaging predictor sensitivity, specificity, accuracy, and association with IAC using Fisher's exact test. Inter-reader agreement determined using Fleiss' kappa statistics.For diagnosis of IAC, sensitivities and specificities were high (70-93%). Pancreatic abnormality was strongest predictor for distinguishing IAC from PSC and cancer, with high diagnostic performance (70-80% sensitivity, 87-97% specificity), significant association (p < 0.01), and moderate inter-reader agreement (κ = 0.59). Continuous biliary involvement was moderately predictive (50-100% sensitivity, 53-83% specificity) and trended toward significant association in distinguishing from PSC (p = 0.01-0.19), but less from cancer (p = 0.06-0.62).It remains difficult to distinguish IAC from PSC or bile duct malignancy based on imaging features alone. The presence of pancreatic abnormalities, including peripancreatic rind, atrophy, abnormal enhancement, or T2 signal intensity, strongly favors a diagnosis of IAC.

Authors
Gardner, CS; Bashir, MR; Marin, D; Nelson, RC; Choudhury, KR; Ho, LM
MLA Citation
Gardner, CS, Bashir, MR, Marin, D, Nelson, RC, Choudhury, KR, and Ho, LM. "Diagnostic performance of imaging criteria for distinguishing autoimmune cholangiopathy from primary sclerosing cholangitis and bile duct malignancy." Abdominal imaging 40.8 (October 2015): 3052-3061.
PMID
26350286
Source
epmc
Published In
Abdominal Imaging
Volume
40
Issue
8
Publish Date
2015
Start Page
3052
End Page
3061
DOI
10.1007/s00261-015-0543-4

High-Pitch Dual-Source MDCT for Imaging of the Thoracoabdominal Aorta: Relationships Among Radiation Dose, Noise, Pitch, and Body Size in a Phantom Experiment and Clinical Study.

The purpose of this study was to investigate, both in a phantom experiment and a within-patient clinical study the relationships among radiation dose, image noise, pitch, and body size in MDCT angiography of the thoracoabdominal aorta, with the use of high-pitch dual-source and standard-pitch single-source acquisitions.A proprietary tapered phantom consisting of four ultrahigh-molecular-weight polyethylene cylinders was used to mimic the body size ranges (small, medium, large, and extra large) of patients in the United States. The phantom was imaged using both standard-pitch (0.8) and various high-pitch (range, 2.0-3.2 [in increments of 0.4]) settings. Standard-pitch and high-pitch acquisitions were also performed in 45 patients (27 men, 18 women; mean age, 67.6 years).At standard pitch, the volume CT dose index (CTDIvol) increased with phantom size, in a logistic sigmoid relationship. At high-pitch settings, the CTDIvol increased gradually in relation to phantom size, up to a threshold (denoted by tCTDI[pitch] ≈ 48.3-7.5 pitch), which linearly decreased (R(2) = 0.99) with pitch (maximum CTDIvol output at pitch [maxCTDI(pitch)] ≈ 18.9-3.9 pitch). A linear decrease in the size-specific dose estimate (SSDE) was observed beyond phantom size thresholds (tSSDE[pitch] ≈ 47.6-8.6 pitch) linearly decreasing (R(2) = 0.98) with pitch (maximum SSDE output at pitch [maxSSDE(pitch)] ≈ 15.5-1.3 pitch). Image noise was statistically significantly lower at standard pitch than at high-pitch settings (p = 0.01). In patients, statistically significant differences were noted between standard and high-pitch settings in the mean CTDIvol(10.8 ± 2.6 and 8.3 ± 0.7 mGy, respectively), SSDE (11.3 ± 2.1 and 8.8 ± 1.5 mGy, respectively), and noise (9.7 ± 2.2 and 14 ± 4.2, respectively) (p < .0001, for all comparisons).Lower radiation dose levels achieved with the use of a high-pitch technique reflect limitations in tube output occurring for medium to large body sizes, with an associated exponential increase in noise. The standard- and high-pitch techniques yield similar radiation dose levels for small body sizes.

Authors
Mileto, A; Ramirez-Giraldo, JC; Nelson, RC; Hurwitz, LM; Choudhury, KR; Seaman, DM; Marin, D
MLA Citation
Mileto, A, Ramirez-Giraldo, JC, Nelson, RC, Hurwitz, LM, Choudhury, KR, Seaman, DM, and Marin, D. "High-Pitch Dual-Source MDCT for Imaging of the Thoracoabdominal Aorta: Relationships Among Radiation Dose, Noise, Pitch, and Body Size in a Phantom Experiment and Clinical Study." AJR. American journal of roentgenology 205.4 (October 2015): 834-839.
PMID
26397333
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
205
Issue
4
Publish Date
2015
Start Page
834
End Page
839
DOI
10.2214/ajr.15.14334

Dual-Energy Multidetector-Row Computed Tomography of the Hepatic Arterial System: Optimization of Energy and Material-Specific Reconstruction Techniques.

To investigate the optimal dual-energy reconstruction technique for the visualization of the hepatic arterial system during dual-energy multidetector computed tomographic (MDCT) angiography of the liver.Twenty-nine nonconsecutive patients underwent dual-energy MDCT angiography of the liver. Synthesized monochromatic (40, 50, 60, and 80 keV) and iodine density data sets were reconstructed. Aortic attenuation, noise, and contrast-to-noise ratio (CNR) were measured. In addition, volume-rendered images were generated and qualitatively assessed by 2 independent readers, blinded to technique. The impact of body size on the readers' scores was also assessed.Aortic attenuation, noise, and CNR increased progressively with decreasing keV and were significantly higher between 40 and 60 keV (P < 0.001). There was a significant improvement of readers' visualization of arterial anatomy at lower monochromatic energies (P < 0.001). Iodine density images yielded significantly higher CNR compared with all monochromatic data sets (P < 0.001). However, iodine density images were scored nondiagnostic by the 2 readers.Synthesized monochromatic images between 40 and 60 keV maximize the magnitude of arterial enhancement and improve visualization of hepatic arterial anatomy at dual-energy MDCT angiography of the liver. Larger body sizes may counteract the benefits of using lower monochromatic energies.

Authors
Marin, D; Caywood, DT; Mileto, A; Reiner, CS; Seaman, DM; Patel, BN; Boll, DT; Nelson, RC
MLA Citation
Marin, D, Caywood, DT, Mileto, A, Reiner, CS, Seaman, DM, Patel, BN, Boll, DT, and Nelson, RC. "Dual-Energy Multidetector-Row Computed Tomography of the Hepatic Arterial System: Optimization of Energy and Material-Specific Reconstruction Techniques." Journal of computer assisted tomography 39.5 (September 2015): 721-729.
PMID
25938210
Source
epmc
Published In
Journal of Computer Assisted Tomography
Volume
39
Issue
5
Publish Date
2015
Start Page
721
End Page
729
DOI
10.1097/rct.0000000000000259

Dual energy CT in renal tumors

Authors
Mileto, A; Marin, D
MLA Citation
Mileto, A, and Marin, D. "Dual energy CT in renal tumors." Dual Energy CT in Oncology. August 19, 2015. 107-122.
Source
scopus
Publish Date
2015
Start Page
107
End Page
122
DOI
10.1007/978-3-319-19563-6_8

Concordance of hypervascular liver nodule characterization between the organ procurement and transplant network and liver imaging reporting and data system classifications.

To determine the rate of agreement between the Organ Procurement and Transplant Network (OPTN) and Liver Imaging Reporting and Data System (LI-RADS) classifications for hypervascular liver nodules at least 1 cm in diameter, and for patient eligibility for hepatocellular/MELD (Model for Endstage Liver Disease) exception points.This retrospective study was approved by our Institutional Review Board and was compliant with the Health Insurance Portability and Accountability Act. The requirement for informed consent was waived. This study included 200 hypervascular hepatocellular nodules at least 1 cm in diameter on computed tomography (CT) or magnetic resonance imaging (MRI) examinations in 105 patients with chronic liver disease. Three radiologists blinded to clinical data independently evaluated nodule characteristics, including washout, capsule, size, and size on prior examination. Based on those characteristics, nodules were automatically classified as definite hepatocellular carcinoma (HCC) or not definite HCC using both the OPTN and LI-RADS classifications. Using these classifications and the Milan criteria, each examination was determined to be "below transplant criteria," "within transplant criteria," or "beyond transplant criteria." Agreement was assessed between readers and classification systems, using Fleiss' kappa, intraclass correlation coefficients (ICCs), and simple proportions.Interreader agreement was moderate for nodule features (κ = 0.59-0.69) and nodule classification (0.66-0.69). The two systems were in nearly complete agreement on nodule category assignment (98.7% [592/600]) and patient eligibility for transplant exemption priority (99.4% [313/315]). A few discrepancies occurred for the nodule feature of growth (1.3% [8/600]) and for nodule category assignment (1.3% [8/600]).Agreement between the OPTN and LI-RADS classifications is very strong for categorization of hypervascular liver nodules at least 1 cm in diameter, and for patient eligibility for hepatocellular/MELD exception points. Interreader variability is much higher than intersystem variability.

Authors
Bashir, MR; Huang, R; Mayes, N; Marin, D; Berg, CL; Nelson, RC; Jaffe, TA
MLA Citation
Bashir, MR, Huang, R, Mayes, N, Marin, D, Berg, CL, Nelson, RC, and Jaffe, TA. "Concordance of hypervascular liver nodule characterization between the organ procurement and transplant network and liver imaging reporting and data system classifications." Journal of magnetic resonance imaging : JMRI 42.2 (August 2015): 305-314.
PMID
25371354
Source
epmc
Published In
Journal of Magnetic Resonance Imaging
Volume
42
Issue
2
Publish Date
2015
Start Page
305
End Page
314
DOI
10.1002/jmri.24793

Image-guided percutaneous drainage vs. surgical repair of gastrointestinal anastomotic leaks: is there a difference in hospital course or hospitalization cost?

To identify differences in hospital course and hospitalization cost when comparing image-guided percutaneous drainage with surgical repair for gastrointestinal anastomotic leaks.A retrospective IRB-approved search using key words "leak" and/or "anastomotic" was performed on all adult CT reports from 2002 to 2011. CT examinations were reviewed for evidence of a postoperative gastrointestinal leak and assigned a confidence score of 1-5 (1 = no leak, 5 = definite leak). Patients with an average confidence score <4 were excluded. Type of surgery, patient data, method of leak management, number of hospital admissions, length of hospital stay, discharge disposition, number of CT examinations, number of drains, and hospitalization costs were collected.One hundred thirty-nine patients had radiographic evidence of a gastrointestinal anastomotic leak (esophageal, gastric, small bowel or colonic). Nine patients were excluded due to low confidence scores. Twenty-seven patients underwent surgical repair (Group A) and 103 were managed entirely with percutaneous image-guided drainage (Group B). There was no significant difference in patient demographics or number of hospital admissions. Patients in Group A had longer median hospital stays compared to Group B (48 vs. 32 days, p = 0.007). The median total hospitalization cost for Group A was more than twice that for Group B ($99,995 vs. $47,838, p = 0.001). Differences in hospital disposition, number of CT examinations, number of drains, and time between original surgery and first CT examination were statistically significant.Gastrointestinal anastomotic leaks managed by percutaneous drainage are associated with lower hospital cost and shorter hospital stays compared with surgical management.

Authors
Burke, LMB; Bashir, MR; Gardner, CS; Parsee, AA; Marin, D; Vermess, D; Bhattacharya, SD; Thacker, JK; Jaffe, TA
MLA Citation
Burke, LMB, Bashir, MR, Gardner, CS, Parsee, AA, Marin, D, Vermess, D, Bhattacharya, SD, Thacker, JK, and Jaffe, TA. "Image-guided percutaneous drainage vs. surgical repair of gastrointestinal anastomotic leaks: is there a difference in hospital course or hospitalization cost?." Abdominal imaging 40.5 (June 2015): 1279-1284.
PMID
25294007
Source
epmc
Published In
Abdominal Imaging
Volume
40
Issue
5
Publish Date
2015
Start Page
1279
End Page
1284
DOI
10.1007/s00261-014-0265-z

Computer-aided liver volumetry: performance of a fully-automated, prototype post-processing solution for whole-organ and lobar segmentation based on MDCT imaging.

To evaluate the performance of a prototype, fully-automated post-processing solution for whole-liver and lobar segmentation based on MDCT datasets.A polymer liver phantom was used to assess accuracy of post-processing applications comparing phantom volumes determined via Archimedes' principle with MDCT segmented datasets. For the IRB-approved, HIPAA-compliant study, 25 patients were enrolled. Volumetry performance compared the manual approach with the automated prototype, assessing intraobserver variability, and interclass correlation for whole-organ and lobar segmentation using ANOVA comparison. Fidelity of segmentation was evaluated qualitatively.Phantom volume was 1581.0 ± 44.7 mL, manually segmented datasets estimated 1628.0 ± 47.8 mL, representing a mean overestimation of 3.0%, automatically segmented datasets estimated 1601.9 ± 0 mL, representing a mean overestimation of 1.3%. Whole-liver and segmental volumetry demonstrated no significant intraobserver variability for neither manual nor automated measurements. For whole-liver volumetry, automated measurement repetitions resulted in identical values; reproducible whole-organ volumetry was also achieved with manual segmentation, p(ANOVA) 0.98. For lobar volumetry, automated segmentation improved reproducibility over manual approach, without significant measurement differences for either methodology, p(ANOVA) 0.95-0.99. Whole-organ and lobar segmentation results from manual and automated segmentation showed no significant differences, p(ANOVA) 0.96-1.00. Assessment of segmentation fidelity found that segments I-IV/VI showed greater segmentation inaccuracies compared to the remaining right hepatic lobe segments.Automated whole-liver segmentation showed non-inferiority of fully-automated whole-liver segmentation compared to manual approaches with improved reproducibility and post-processing duration; automated dual-seed lobar segmentation showed slight tendencies for underestimating the right hepatic lobe volume and greater variability in edge detection for the left hepatic lobe compared to manual segmentation.

Authors
Fananapazir, G; Bashir, MR; Marin, D; Boll, DT
MLA Citation
Fananapazir, G, Bashir, MR, Marin, D, and Boll, DT. "Computer-aided liver volumetry: performance of a fully-automated, prototype post-processing solution for whole-organ and lobar segmentation based on MDCT imaging." Abdominal imaging 40.5 (June 2015): 1203-1212.
PMID
25326261
Source
epmc
Published In
Abdominal Imaging
Volume
40
Issue
5
Publish Date
2015
Start Page
1203
End Page
1212
DOI
10.1007/s00261-014-0276-9

Dual-Energy MDCT for Imaging the Renal Mass.

OBJECTIVE: The purpose of this article is to provide the reader with a comprehensive overview of dual-energy MDCT applications for imaging renal masses. CONCLUSION: Dual-energy MDCT has the potential to substantially improve the ability of radiologists to diagnose renal masses compared with conventional MDCT, potentially streamlining patients' clinical management.

Authors
Mileto, A; Nelson, RC; Paulson, EK; Marin, D
MLA Citation
Mileto, A, Nelson, RC, Paulson, EK, and Marin, D. "Dual-Energy MDCT for Imaging the Renal Mass." AJR. American journal of roentgenology 204.6 (June 2015): W640-W647.
PMID
25730444
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
204
Issue
6
Publish Date
2015
Start Page
W640
End Page
W647
DOI
10.2214/ajr.14.14094

Emerging applications for ferumoxytol as a contrast agent in MRI.

Ferumoxytol is an ultrasmall superparamagnetic iron oxide (USPIO) agent initially approved by the Food and Drug Administration (FDA) as an iron replacement therapy for patients with anemia due to chronic renal failure. Recently, ferumoxytol has been investigated extensively as an intravenous contrast agent in magnetic resonance imaging (MRI). Since it causes regional T1 and T2 * shortening in vivo, conventional pulse sequences can be used following ferumoxytol administration to demonstrate signal enhancement or loss. Ferumoxytol can be administered as a rapid bolus and has a long intravascular half-life on the order of 14-15 hours, making it a potentially useful agent for vascular and perfusion-weighted MRI. In comparison to other USPIOs, ferumoxytol is less limited by allergic and idiosyncratic reactions. Furthermore, since ferumoxytol is an iron-based agent with no potential for causing nephrogenic systemic fibrosis, it may be useful as an alternative to gadolinium-based contrast agents in patients with compromised renal function. Ferumoxytol is ultimately taken up by macrophages/the reticuloendothelial system in the liver, spleen, and lymph nodes, and this uptake mechanism is being explored as a novel imaging technique for vascular lesions, tumors, and lymph nodes. This article reviews the properties of ferumoxytol relevant to MRI as well as many of the uses for the agent currently under investigation.

Authors
Bashir, MR; Bhatti, L; Marin, D; Nelson, RC
MLA Citation
Bashir, MR, Bhatti, L, Marin, D, and Nelson, RC. "Emerging applications for ferumoxytol as a contrast agent in MRI." Journal of magnetic resonance imaging : JMRI 41.4 (April 2015): 884-898.
PMID
24974785
Source
epmc
Published In
Journal of Magnetic Resonance Imaging
Volume
41
Issue
4
Publish Date
2015
Start Page
884
End Page
898
DOI
10.1002/jmri.24691

Interdependencies of acquisition, detection, and reconstruction techniques on the accuracy of iodine quantification in varying patient sizes employing dual-energy CT.

PURPOSE: To assess the impact of patient habitus, acquisition parameters, detector efficiencies, and reconstruction techniques on the accuracy of iodine quantification using dual-source dual-energy CT (DECT). MATERIALS AND METHODS: Two phantoms simulating small and large patients contained 20 iodine solutions mimicking vascular and parenchymal enhancement from saline isodensity to 400 HU and 30 iodine solutions simulating enhancement of the urinary collecting system from 400 to 2,000 HU. DECT acquisition (80/140 kVp and 100/140 kVp) was performed using two DECT systems equipped with standard and integrated electronics detector technologies. DECT raw datasets were reconstructed using filtered backprojection (FBP), and iterative reconstruction (SAFIRE I/V). RESULTS: Accuracy for iodine quantification was significantly higher for the small compared to the large phantoms (9.2 % ± 7.5 vs. 24.3 % ± 26.1, P = 0.0001), the integrated compared to the conventional detectors (14.8 % ± 20.6 vs. 18.8 % ± 20.4, respectively; P = 0.006), and SAFIRE V compared to SAFIRE I and FBP reconstructions (15.2 % ± 18.1 vs. 16.1 % ± 17.6 and 18.9 % ± 20.4, respectively; P ≤ 0.003). A significant synergism was observed when the most effective detector and reconstruction techniques were combined with habitus-adapted dual-energy pairs. CONCLUSION: In a second-generation dual-source DECT system, the accuracy of iodine quantification can be substantially improved by an optimal choice and combination of acquisition parameters, detector, and reconstruction techniques.

Authors
Marin, D; Pratts-Emanuelli, JJ; Mileto, A; Husarik, DB; Bashir, MR; Nelson, RC; Boll, DT
MLA Citation
Marin, D, Pratts-Emanuelli, JJ, Mileto, A, Husarik, DB, Bashir, MR, Nelson, RC, and Boll, DT. "Interdependencies of acquisition, detection, and reconstruction techniques on the accuracy of iodine quantification in varying patient sizes employing dual-energy CT." European radiology 25.3 (March 2015): 679-686.
PMID
25278247
Source
epmc
Published In
European Radiology
Volume
25
Issue
3
Publish Date
2015
Start Page
679
End Page
686
DOI
10.1007/s00330-014-3447-8

Dual-energy multidetector CT for the characterization of incidental adrenal nodules: diagnostic performance of contrast-enhanced material density analysis.

PURPOSE: To determine whether contrast material-enhanced dual-energy multidetector computed tomography (CT) with material decomposition analysis allows differentiation of adrenal adenomas from nonadenomatous lesions and to compare findings with those of nonenhanced multidetector CT. MATERIALS AND METHODS: This retrospective HIPAA-compliant study was approved by the institutional review board of Duke University, with waiver of informed consent. Thirty-eight nonconsecutive patients (22 men and 16 women; mean age, 65 years) with 47 adrenal nodules underwent nonenhanced and contrast-enhanced dual-energy multidetector CT of the abdomen. For each adrenal nodule, nonenhanced attenuation values were recorded; dual-energy density measurements were obtained by using fat-iodine and fat-water material density basis pairs. Mean and median values of nonenhanced attenuation and material densities were compared between adenomas and nonadenomas by using the two-sample t test and Wilcoxon rank sum test, respectively. The diagnostic performance of nonenhanced multidetector CT and dual-energy material densities was assessed by setting the specificity for diagnosis of adenomas at 100%. RESULTS: Adenomas (lipid rich and lipid poor) displayed significantly different mean density values (in milligrams per cubic centimeter) than those of nonadenomas on fat-iodine (970.4 ± 17.2 vs 1012.3 ± 9.3), iodine-fat (2.5 ± 0.3 vs 4.5 ± 1.5), fat-water (-666.7 ± 154.8 vs -2141.8 ± 953.2), and water-fat (1628.4 ± 177.3 vs 3225 ± 986.1) images, respectively (P < .0001). For diagnosis of adenomas, dual-energy material density analysis showed a sensitivity of 96% (23 of 24 lesions) at a specificity of 100% (23 of 23 lesions), yielding significantly improved diagnostic performance compared with nonenhanced multidetector CT attenuation (sensitivity of 67% [16 of 24 lesions] at a specificity of 100% [23 of 23 lesions]) (P = .035). CONCLUSION: Contrast-enhanced dual-energy multidetector CT with material density analysis allows differentiation between adrenal adenomas and nonadenomas, reflecting an improved ability over nonenhanced multidetector CT for diagnosis of lipid-poor adenoma.

Authors
Mileto, A; Nelson, RC; Marin, D; Roy Choudhury, K; Ho, LM
MLA Citation
Mileto, A, Nelson, RC, Marin, D, Roy Choudhury, K, and Ho, LM. "Dual-energy multidetector CT for the characterization of incidental adrenal nodules: diagnostic performance of contrast-enhanced material density analysis." Radiology 274.2 (February 2015): 445-454.
PMID
25207467
Source
epmc
Published In
Radiology
Volume
274
Issue
2
Publish Date
2015
Start Page
445
End Page
454
DOI
10.1148/radiol.14140876

Determination of contrast media administration to achieve a targeted contrast enhancement in CT

© 2015 SPIE.Contrast enhancement is a key component of CT imaging and offer opportunities for optimization. The design and optimization of new techniques however requires orchestration with the scan parameters and further a methodology to relate contrast enhancement and injection function. In this study, we used such a methodology to develop a method, analytical inverse method, to predict the required injection function to achieve a desired contrast enhancement in a given organ by incorporation of a physiologically based compartmental model. The method was evaluated across 32 different target contrast enhancement functions for aorta, kidney, stomach, small intestine, and liver. The results exhibited that the analytical inverse method offers accurate performance with error in the range of 10% deviation between the predicted and desired organ enhancement curves. However, this method is incapable of predicting the injection function based on the liver enhancement. The findings of this study can be useful in optimizing contrast medium injection function as well as the scan timing to provide more consistency in the way that the contrast enhanced CT examinations are performed. To our knowledge, this work is one of the first attempts to predict the contrast material injection function for a desired organ enhancement curve.

Authors
Sahbaee, P; Li, Y; Segars, P; Marin, D; Nelson, R; Samei, E
MLA Citation
Sahbaee, P, Li, Y, Segars, P, Marin, D, Nelson, R, and Samei, E. "Determination of contrast media administration to achieve a targeted contrast enhancement in CT." January 1, 2015.
Source
scopus
Published In
Proceedings of SPIE
Volume
9412
Publish Date
2015
DOI
10.1117/12.2082261

Respiratory motion artifact affecting hepatic arterial phase MR imaging with gadoxetate disodium is more common in patients with a prior episode of arterial phase motion associated with gadoxetate disodium.

PURPOSE: To determine, in a dual-center setting, whether patients who experience transient severe motion ( TSM transient severe motion ) in the arterial phase during gadoxetate disodium-enhanced magnetic resonance (MR) imaging are at higher risk for a subsequent episode of TSM transient severe motion than patients who do not have TSM transient severe motion during initial gadoxetate disodium administration. MATERIALS AND METHODS: Institutional review board approval was obtained for this retrospective, multi-institutional HIPAA-compliant study. The requirement for informed consent was waived. One hundred seventy patients each underwent two MR imaging examinations with bolus injection of gadoxetate disodium at one of two sites. Three radiologists reviewed the examinations at each site for TSM transient severe motion , based on severe arterial phase motion, despite minimal motion in the other dynamic phases. The occurrence rate of TSM transient severe motion in the second examination was compared between patients who had TSM transient severe motion in their first examination and those who did not by using the χ(2) or Fisher exact test, as appropriate. Relative risks and 95% confidence intervals ( CI confidence interval s) were calculated. RESULTS: TSM transient severe motion rates in second examinations were significantly higher for patients who had TSM transient severe motion in their first examination: site 1, 67% (six of nine) vs 4% (three of 69) (P < .0001); site 2, 60% (three of five) vs 6% (five of 87) (P < .005); and both sites, 64% (nine of 14) vs 5% (eight of 156) (P < .0001). Relative risks were 15 for site 1 (95% CI confidence interval : 5, 51), 10 for site 2 (95% CI confidence interval : 3, 32), and 13 for both sites (95% CI confidence interval : 6, 27). CONCLUSION: Patients who experience TSM transient severe motion during gadoxetate disodium-enhanced MR imaging are at significantly and substantially higher risk for TSM transient severe motion in the next gadoxetate disodium-enhanced examination compared with patients who do not have TSM transient severe motion during their initial gadoxetate disodium administration.

Authors
Bashir, MR; Castelli, P; Davenport, MS; Larson, D; Marin, D; Hussain, HK; Jaffe, TA
MLA Citation
Bashir, MR, Castelli, P, Davenport, MS, Larson, D, Marin, D, Hussain, HK, and Jaffe, TA. "Respiratory motion artifact affecting hepatic arterial phase MR imaging with gadoxetate disodium is more common in patients with a prior episode of arterial phase motion associated with gadoxetate disodium." Radiology 274.1 (January 2015): 141-148.
PMID
25162310
Source
epmc
Published In
Radiology
Volume
274
Issue
1
Publish Date
2015
Start Page
141
End Page
148
DOI
10.1148/radiol.14140386

Emerging applications for ferumoxytol as a contrast agent in MRI

© 2014 Wiley Periodicals, Inc. © 2014 Wiley Periodicals, Inc.Ferumoxytol is an ultrasmall superparamagnetic iron oxide (USPIO) agent initially approved by the Food and Drug Administration (FDA) as an iron replacement therapy for patients with anemia due to chronic renal failure. Recently, ferumoxytol has been investigated extensively as an intravenous contrast agent in magnetic resonance imaging (MRI). Since it causes regional T1 and T2∗ shortening in vivo, conventional pulse sequences can be used following ferumoxytol administration to demonstrate signal enhancement or loss. Ferumoxytol can be administered as a rapid bolus and has a long intravascular half-life on the order of 14-15 hours, making it a potentially useful agent for vascular and perfusion-weighted MRI. In comparison to other USPIOs, ferumoxytol is less limited by allergic and idiosyncratic reactions. Furthermore, since ferumoxytol is an iron-based agent with no potential for causing nephrogenic systemic fibrosis, it may be useful as an alternative to gadolinium-based contrast agents in patients with compromised renal function. Ferumoxytol is ultimately taken up by macrophages/the reticuloendothelial system in the liver, spleen, and lymph nodes, and this uptake mechanism is being explored as a novel imaging technique for vascular lesions, tumors, and lymph nodes. This article reviews the properties of ferumoxytol relevant to MRI as well as many of the uses for the agent currently under investigation.

Authors
Bashir, MR; Bhatti, L; Marin, D; Nelson, RC
MLA Citation
Bashir, MR, Bhatti, L, Marin, D, and Nelson, RC. "Emerging applications for ferumoxytol as a contrast agent in MRI." Journal of Magnetic Resonance Imaging 41.4 (2015): 884-898.
Source
scival
Published In
Journal of Magnetic Resonance Imaging
Volume
41
Issue
4
Publish Date
2015
Start Page
884
End Page
898
DOI
10.1002/jmri.24691

Iodine quantification to distinguish clear cell from papillary renal cell carcinoma at dual-energy multidetector CT: a multireader diagnostic performance study.

PURPOSE: To investigate whether dual-energy multidetector row computed tomographic (CT) imaging with iodine quantification is able to distinguish between clear cell and papillary renal cell carcinoma ( RCC renal cell carcinoma ) subtypes. MATERIALS AND METHODS: In this retrospective, HIPAA-compliant, institutional review board-approved study, 88 patients (57 men, 31 women) with diagnosis of either clear cell or papillary RCC renal cell carcinoma at pathologic analysis, who underwent contrast material-enhanced dual-energy nephrographic phase study between December 2007 and June 2013, were included. Five readers, blinded to pathologic diagnosis, independently evaluated all cases by determining the lesion iodine concentration on color-coded iodine maps. The receiving operating characteristic curve analysis was adopted to estimate the optimal threshold for discriminating between clear cell and papillary RCC renal cell carcinoma , and results were validated by using a leave-one-out cross-validation. Interobserver agreement was assessed by using an intraclass correlation coefficient. The correlation between tumor iodine concentration and tumor grade was investigated. RESULTS: A tumor iodine concentration of 0.9 mg/mL represented the optimal threshold to discriminate between clear cell and papillary RCC renal cell carcinoma , and it yielded the following: sensitivity, 98.2% (987 of 1005 [95% confidence interval: 97.7%, 98.7%]); specificity, 86.3% (272 of 315 [95% confidence interval: 85.0%, 87.7%]); positive predictive value, 95.8% (987 of 1030 [95% confidence interval: 95.0%, 96.6%]); negative predictive value, 93.7% (272 of 290 [95% confidence interval: 92.8%, 94.7%]); overall accuracy of 95.3% (1259 of 1320 [95% confidence interval: 94.6%, 96.2%]), with an area under the curve of 0.923 (95% confidence interval: 0.913, 0.933). An excellent agreement was found among the five readers in measured tumor iodine concentration (intraclass correlation coefficient, 0.9990 [95% confidence interval: 0. 9987, 0.9993). A significant correlation was found between tumor iodine concentration and tumor grade for both clear cell (τ = 0.85; P < .001) and papillary RCC renal cell carcinoma (τ = 0.53; P < .001). CONCLUSION: Dual-energy multidetector CT with iodine quantification can be used to distinguish between clear cell and papillary RCC renal cell carcinoma , and it provides insights regarding the tumor grade.

Authors
Mileto, A; Marin, D; Alfaro-Cordoba, M; Ramirez-Giraldo, JC; Eusemann, CD; Scribano, E; Blandino, A; Mazziotti, S; Ascenti, G
MLA Citation
Mileto, A, Marin, D, Alfaro-Cordoba, M, Ramirez-Giraldo, JC, Eusemann, CD, Scribano, E, Blandino, A, Mazziotti, S, and Ascenti, G. "Iodine quantification to distinguish clear cell from papillary renal cell carcinoma at dual-energy multidetector CT: a multireader diagnostic performance study." Radiology 273.3 (December 2014): 813-820.
PMID
25162309
Source
epmc
Published In
Radiology
Volume
273
Issue
3
Publish Date
2014
Start Page
813
End Page
820
DOI
10.1148/radiol.14140171

Dual-energy MDCT in hypervascular liver tumors: effect of body size on selection of the optimal monochromatic energy level.

OBJECTIVE: The purpose of this article is to investigate the effect of body size on the selection of optimal monochromatic energy level for maximizing the conspicuity of hypervascular liver tumors during late hepatic arterial phase using dual-energy MDCT. MATERIALS AND METHODS: An anthropomorphic liver phantom in three body sizes and iodine-containing inserts simulating low- and high-contrast hypervascular lesions was imaged with dual- and single-energy MDCT at various energy levels (80, 100, 120, and 140 kVp). Dual-energy MDCT was also performed in 48 patients with 114 hypervascular liver tumors; virtual monochromatic images were reconstructed at energy levels from 40 to 140 keV. The effect of body size and lesion iodine concentration on noise and tumor-to-liver contrast-to-noise ratio was compared among different datasets for phantoms and patients. RESULTS: The highest tumor-to-liver contrast-to-noise ratio was noted at 80 kVp for all phantom sizes. On virtual monochromatic images, the minimum noise was noted at 70 keV for small and medium phantoms and at 80 keV for the large phantom. Tumor-to-liver contrast-to-noise ratio was highest at 50 keV for small and medium phantoms and at 60 keV for the large phantom (p<0.0001). Compared with 80-kVp images, an optimal monochromatic energy level yielded a significantly higher (p<0.0001) tumor-to-liver contrast-to-noise ratio for high-contrast lesions in the large body size and for low-contrast lesions in all phantom sizes. In patients, the optimal monochromatic energy level for tumor-to-liver contrast-to-noise ratio increased proportionally along with body size (p<0.0001). CONCLUSION: Selection of the optimal monochromatic energy level for maximizing the conspicuity of hypervascular liver tumors is significantly affected by patient's body size.

Authors
Mileto, A; Nelson, RC; Samei, E; Choudhury, KR; Jaffe, TA; Wilson, JM; Marin, D
MLA Citation
Mileto, A, Nelson, RC, Samei, E, Choudhury, KR, Jaffe, TA, Wilson, JM, and Marin, D. "Dual-energy MDCT in hypervascular liver tumors: effect of body size on selection of the optimal monochromatic energy level." AJR. American journal of roentgenology 203.6 (December 2014): 1257-1264.
PMID
25415703
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
203
Issue
6
Publish Date
2014
Start Page
1257
End Page
1264
DOI
10.2214/ajr.13.12229

Image-guided percutaneous drainage vs. surgical repair of gastrointestinal anastomotic leaks: is there a difference in hospital course or hospitalization cost?

© 2014, Springer Science+Business Media New York.Purpose: To identify differences in hospital course and hospitalization cost when comparing image-guided percutaneous drainage with surgical repair for gastrointestinal anastomotic leaks. Materials and methods: A retrospective IRB-approved search using key words “leak” and/or “anastomotic” was performed on all adult CT reports from 2002 to 2011. CT examinations were reviewed for evidence of a postoperative gastrointestinal leak and assigned a confidence score of 1–5 (1 = no leak, 5 = definite leak). Patients with an average confidence score <4 were excluded. Type of surgery, patient data, method of leak management, number of hospital admissions, length of hospital stay, discharge disposition, number of CT examinations, number of drains, and hospitalization costs were collected. Results: One hundred thirty-nine patients had radiographic evidence of a gastrointestinal anastomotic leak (esophageal, gastric, small bowel or colonic). Nine patients were excluded due to low confidence scores. Twenty-seven patients underwent surgical repair (Group A) and 103 were managed entirely with percutaneous image-guided drainage (Group B). There was no significant difference in patient demographics or number of hospital admissions. Patients in Group A had longer median hospital stays compared to Group B (48 vs. 32 days, p = 0.007). The median total hospitalization cost for Group A was more than twice that for Group B ($99,995 vs. $47,838, p = 0.001). Differences in hospital disposition, number of CT examinations, number of drains, and time between original surgery and first CT examination were statistically significant. Conclusion: Gastrointestinal anastomotic leaks managed by percutaneous drainage are associated with lower hospital cost and shorter hospital stays compared with surgical management.

Authors
Burke, LMB; Bashir, MR; Gardner, CS; Parsee, AA; Marin, D; Vermess, D; Bhattacharya, SD; Thacker, JK; Jaffe, TA
MLA Citation
Burke, LMB, Bashir, MR, Gardner, CS, Parsee, AA, Marin, D, Vermess, D, Bhattacharya, SD, Thacker, JK, and Jaffe, TA. "Image-guided percutaneous drainage vs. surgical repair of gastrointestinal anastomotic leaks: is there a difference in hospital course or hospitalization cost?." Abdominal Imaging 40.5 (October 8, 2014): 1279-1284.
Source
scopus
Published In
Abdominal Imaging
Volume
40
Issue
5
Publish Date
2014
Start Page
1279
End Page
1284
DOI
10.1007/s00261-014-0265-z

Nonlinear image blending for dual-energy MDCT of the abdomen: can image quality be preserved if the contrast medium dose is reduced?

OBJECTIVE: The objective of this study was to compare the image quality of a dual-energy nonlinear image blending technique at reduced load of contrast medium with a simulated 120-kVp linear blending technique at a full dose during portal venous phase MDCT of the abdomen. SUBJECTS AND METHODS: Forty-five patients (25 men, 20 women; mean age, 65.6 ± 9.7 [SD] years; mean body weight, 74.9 ± 12.4 kg) underwent contrast-enhanced single-phase dual-energy CT of the abdomen by a random assignment to one of three different contrast medium (iomeprol 400) dose injection protocols: 1.3, 1.0, or 0.65 mL/kg of body weight. The contrast-to-noise ratio (CNR) and noise at the portal vein, liver, aorta, and kidney were compared among the different datasets using the ANOVA. Three readers qualitatively assessed all datasets in a blinded and independent fashion. RESULTS: Nonlinear blended images at a 25% reduced dose allowed a significant improvement in CNR (p < 0.05 for all comparisons), compared with simulated 120-kVp linear blended images at a full dose. No statistically significant difference existed in CNR and noise between the nonlinear blended images at a 50% reduced dose and the simulated 120-kVp linear blended images at a full dose. Nonlinear blended images at a 50% reduced dose were considered in all cases to have acceptable image quality. CONCLUSION: The dual-energy nonlinear image blending technique allows reducing the dose of contrast medium up to 50% during portal venous phase imaging of the abdomen while preserving image quality.

Authors
Mileto, A; Ramirez-Giraldo, JC; Marin, D; Alfaro-Cordoba, M; Eusemann, CD; Scribano, E; Blandino, A; Mazziotti, S; Ascenti, G
MLA Citation
Mileto, A, Ramirez-Giraldo, JC, Marin, D, Alfaro-Cordoba, M, Eusemann, CD, Scribano, E, Blandino, A, Mazziotti, S, and Ascenti, G. "Nonlinear image blending for dual-energy MDCT of the abdomen: can image quality be preserved if the contrast medium dose is reduced?." AJR. American journal of roentgenology 203.4 (October 2014): 838-845.
PMID
25247950
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
203
Issue
4
Publish Date
2014
Start Page
838
End Page
845
DOI
10.2214/ajr.13.12179

Dual-energy multi-detector row CT with virtual monochromatic imaging for improving patient-to-patient uniformity of aortic enhancement during CT angiography: an in vitro and in vivo study.

PURPOSE: To determine whether virtual monochromatic imaging from a dual-energy acquisition can improve patient-to-patient uniformity of aortic enhancement during multi-detector row computed tomographic (CT) angiography. MATERIALS AND METHODS: This retrospective single-center HIPAA-compliant study was approved by the institutional review board, with a waiver of informed consent. A proprietary tapered hollow phantom that contained a bone-mimicking insert and a hollow tube insert that mimicked the aorta was used. The aortic insert was filled with different iodine dilutions to mimic various degrees of enhancement. The phantom was imaged with both dual-energy and single-energy multi-detector row CT at four energy levels (80, 100, 120, and 140 kVp). Dual-energy multi-detector row CT was also performed in 62 patients (38 men; mean age, 60 years ± 12.7 [standard deviation]). For both the phantom and the patients, virtual monochromatic images were reconstructed from 40 to 140 keV, at 20-keV increments. The relationship between aortic attenuation and effective diameter was assessed by using a statistical model. RESULTS: For all polychromatic data sets, the mean aortic attenuation decreased proportionally to the effective diameter of the phantom (slope, ≥3.0 HU/cm). For virtual monochromatic data sets ranging from 80 to 140 keV, the regression slopes of aortic attenuation as a function of the phantom's effective diameter were negligible (slope, <1.0 HU/cm) for all iodine-to-water dilutions. In patients, the slope of the regression lines was also negligible (-0.69 < slope < 0.16) for virtual monochromatic data sets ranging from 100 to 140 keV. CONCLUSION: Within an energy range of 100-140 keV, virtual monochromatic images improve patient-to-patient uniformity of aortic enhancement compared with conventional polychromatic acquisitions.

Authors
Marin, D; Fananapazir, G; Mileto, A; Choudhury, KR; Wilson, JM; Nelson, RC
MLA Citation
Marin, D, Fananapazir, G, Mileto, A, Choudhury, KR, Wilson, JM, and Nelson, RC. "Dual-energy multi-detector row CT with virtual monochromatic imaging for improving patient-to-patient uniformity of aortic enhancement during CT angiography: an in vitro and in vivo study." Radiology 272.3 (September 2014): 895-902.
PMID
24814182
Source
epmc
Published In
Radiology
Volume
272
Issue
3
Publish Date
2014
Start Page
895
End Page
902
DOI
10.1148/radiol.14132857

Impact of dual-energy multi-detector row CT with virtual monochromatic imaging on renal cyst pseudoenhancement: in vitro and in vivo study.

PURPOSE: To investigate whether dual-energy multi-detector row computed tomography (CT) with virtual monochromatic imaging can overcome renal cyst pseudoenhancement in a phantom experiment and a clinical study. MATERIALS AND METHODS: This retrospective single-center HIPAA-compliant study was approved by the institutional review board, with waiver of informed consent. Four renal compartments inserted into torso phantoms were filled with saline to simulate the unenhanced state and with iodinated solutions to simulate the three levels of renal parenchyma enhancement (140, 180, and 240 HU). Saline-filled spheres simulating renal cysts (15 and 18 mm in diameter) were serially suspended in the renal compartments and imaged with dual-energy and single-energy multi-detector row CT at four different energy levels (80, 100, 120, and 140 kVp). In addition, 28 patients (mean age, 66 years ± 10; mean body mass index, 31.3 kg/m(2) ± 6.2) with 34 intrarenal cysts were included. Virtual monochromatic images were reconstructed in 10-keV increments at energy levels ranging from 40 to 140 keV. Phantom and clinical data were analyzed by using multivariate regression analysis. RESULTS: In the phantom experiment, all polychromatic image data sets showed pseudoenhancement (postcontrast attenuation increase >10 HU) in all investigated conditions, with a significant effect on cyst size (P <.001), location (P <.001), and renal background attenuation level (P <.001). Virtual monochromatic images at energy levels ranging from 80 to 140 keV did not show pseudoenhancement, with the minimum attenuation increase (mean, 6.1 HU ± 1.6; range, 1.6-7.7 HU) on 80-keV images. In patients, pseudoenhancement never occurred on virtual monochromatic images at energy levels ranging from 90 to 140 keV. Patient body size had a significant effect (P = .007) on selection of the optimal monochromatic energy level. CONCLUSION: Dual-energy multi-detector row CT with reconstruction of virtual monochromatic images at an optimal energy level can overcome renal cyst pseudoenhancement.

Authors
Mileto, A; Nelson, RC; Samei, E; Jaffe, TA; Paulson, EK; Barina, A; Choudhury, KR; Wilson, JM; Marin, D
MLA Citation
Mileto, A, Nelson, RC, Samei, E, Jaffe, TA, Paulson, EK, Barina, A, Choudhury, KR, Wilson, JM, and Marin, D. "Impact of dual-energy multi-detector row CT with virtual monochromatic imaging on renal cyst pseudoenhancement: in vitro and in vivo study." Radiology 272.3 (September 2014): 767-776.
PMID
24844472
Source
epmc
Published In
Radiology
Volume
272
Issue
3
Publish Date
2014
Start Page
767
End Page
776
DOI
10.1148/radiol.14132856

Vascular artifact mimicking thrombosis on MR imaging using ferumoxytol as a contrast agent in abdominal vascular assessment.

PURPOSE: To describe an artifact that mimics thrombosis when assessing abdominal vasculature on magnetic resonance (MR) imaging using ferumoxytol in patients with contraindications to gadolinium-based contrast agents and to evaluate factors that may contribute to this artifact. MATERIALS AND METHODS: Three radiologists in consensus retrospectively evaluated 61 abdominal MR imaging examinations using ferumoxytol as an intravenous contrast agent for the presence of an observed artifact that can mimic thrombosis. Patient demographics and contrast agent bolus concentrations were compared with an unpaired Wilcoxon signed rank test. RESULTS: An artifact mimicking thrombosis was observed in 30 of 61 examinations, all on the arterial phase sequences. In examinations with this artifact, the average concentration of administered ferumoxytol was greater than in examinations where the artifact was not observed (P < .01). Several additional vascular findings were observed, including portal vein thrombosis (n = 2) and aneurysm (n = 1), renal vein thrombosis (n = 2), abdominal aortic aneurysm (n = 1), abdominal and iliac artery dissection (n = 3), and sequelae of portal hypertension (n = 8). CONCLUSIONS: Although MR imaging using ferumoxytol as an intravenous contrast agent can be useful in detecting abdominal vascular abnormalities, an artifact mimicking vascular thrombosis was observed in nearly half of the examinations.

Authors
Fananapazir, G; Marin, D; Suhocki, PV; Kim, CY; Bashir, MR
MLA Citation
Fananapazir, G, Marin, D, Suhocki, PV, Kim, CY, and Bashir, MR. "Vascular artifact mimicking thrombosis on MR imaging using ferumoxytol as a contrast agent in abdominal vascular assessment." Journal of vascular and interventional radiology : JVIR 25.6 (June 2014): 969-976.
PMID
24630749
Source
epmc
Published In
JVIR: Journal of Vascular and Interventional Radiology
Volume
25
Issue
6
Publish Date
2014
Start Page
969
End Page
976
DOI
10.1016/j.jvir.2013.12.019

Adrenal glands

© Springer-Verlag Italia 2014. All rights reserved.The adrenal glands can develop a myriad of abnormalities, which can be fundamentally differentiated into benign or malignant lesions having either hyperfunction or non-hyperfunction (i.e., non-function) [1, 2]. Functioning lesions typically secrete hormonal metabolites and include a variety of tumors, some of which are very rare. These tumors can produce cortisol, aldosterone, and sex hormones as well as adrenergic hormones in the case of pheochromocytomas [1-3]. Non-functioning tumors are far more common and include both benign and malignant lesions. Benign masses include cortical adenomas, myelolipomas, cysts and less commonly ganglioneuromas, hemangioendotheliomas, hemorrhage, and granulomatous disease. Malignant lesions include metastases, lymphoma, neuroblastoma, adrenocortical carcinoma, and some forms of pheochromocytomas [1-3].

Authors
Mileto, A; Marin, D; Ho, LM; Nelson, RC
MLA Citation
Mileto, A, Marin, D, Ho, LM, and Nelson, RC. "Adrenal glands." CT of the Retroperitoneum: From Conventional to Multi-energy Imaging. May 1, 2014. 69-81.
Source
scopus
Volume
9788847054691
Publish Date
2014
Start Page
69
End Page
81
DOI
10.1007/978-88-470-5469-1-6

Respiratory motion artifact affecting hepatic arterial phase imaging with gadoxetate disodium: examination recovery with a multiple arterial phase acquisition.

PURPOSE: To determine whether the use of a multiple arterial phase imaging technique provides adequate image quality in patients experiencing transient severe motion (TSM) in the arterial phase on abdominal magnetic resonance (MR) images obtained with gadoxetate disodium. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board and was compliant with HIPAA. The requirement to obtain informed consent was waived. Five hundred forty-nine consecutive MR examinations were evaluated, 345 performed with gadoxetate disodium and 204 performed with gadobenate dimeglumine. All examinations included single-breath-hold triple arterial phase acquisition. Five radiologists blinded to the contrast material rated motion on a scale of 1 (no motion) to 5 (nondiagnostic images) for the precontrast phase, the three arterial phases, the portal venous phase, and the late dynamic phase. Adequacy of late hepatic arterial timing was also rated for the each of the three arterial phases. Mean motion scores were compared by using the Wilcoxon signed rank test. The number of patients with TSM, as well as the number of those with "adequate" arterial phases, was compared with the χ(2) or Fisher exact test, as appropriate. RESULTS: Mean motion scores in all three arterial phases in the gadoxetate disodium cohort were significantly worse than those in the gadobenate dimeglumine cohort (P < .005). TSM occurred at a higher rate with gadoxetate disodium than with gadobenate dimeglumine (10.7% [37 of 345 examinations] vs 0.5% [one of 204 examinations], P < .001). However, 30 of 37 examinations affected by TSM had at least one well-timed arterial phase with a mean motion score of 3 or less and were thus considered adequate. CONCLUSION: Use of single-breath-hold multiple arterial phase acquisition in abdominal MR imaging with gadoxetate disodium recovers most arterial phases that would otherwise have been compromised by transient motion.

Authors
Pietryga, JA; Burke, LMB; Marin, D; Jaffe, TA; Bashir, MR
MLA Citation
Pietryga, JA, Burke, LMB, Marin, D, Jaffe, TA, and Bashir, MR. "Respiratory motion artifact affecting hepatic arterial phase imaging with gadoxetate disodium: examination recovery with a multiple arterial phase acquisition." Radiology 271.2 (May 2014): 426-434.
PMID
24475864
Source
epmc
Published In
Radiology
Volume
271
Issue
2
Publish Date
2014
Start Page
426
End Page
434
DOI
10.1148/radiol.13131988

State of the art: dual-energy CT of the abdomen.

Recent technologic advances in computed tomography (CT)--enabling the nearly simultaneous acquisition of clinical images using two different x-ray energy spectra--have sparked renewed interest in dual-energy CT. By interrogating the unique characteristics of different materials at different x-ray energies, dual-energy CT can be used to provide quantitative information about tissue composition, overcoming the limitations of attenuation-based conventional single-energy CT imaging. In the past few years, intensive research efforts have been devoted to exploiting the unique and powerful opportunities of dual-energy CT for a variety of clinical applications. This has led to CT protocol modifications for radiation dose reduction, improved diagnostic performance for detection and characterization of diseases, as well as image quality optimization. In this review, the authors discuss the basic principles, instrumentation and design, examples of current clinical applications in the abdomen and pelvis, and future opportunities of dual-energy CT.

Authors
Marin, D; Boll, DT; Mileto, A; Nelson, RC
MLA Citation
Marin, D, Boll, DT, Mileto, A, and Nelson, RC. "State of the art: dual-energy CT of the abdomen." Radiology 271.2 (May 2014): 327-342.
PMID
24761954
Source
epmc
Published In
Radiology
Volume
271
Issue
2
Publish Date
2014
Start Page
327
End Page
342
DOI
10.1148/radiol.14131480

Accuracy of contrast-enhanced dual-energy MDCT for the assessment of iodine uptake in renal lesions.

OBJECTIVE: The objective of our study was to assess the accuracy of iodine-related attenuation and iodine quantification as imaging biomarkers of iodine uptake in renal lesions on a single-phase nephrographic image with dual-energy MDCT. MATERIALS AND METHODS: Fifty-nine patients (41 men, 18 women; age range, 28-84 years) with 80 renal lesions underwent contrast-enhanced dual-energy CT during the nephrographic phase of enhancement. Renal lesions were characterized as enhancing or nonenhancing on color-coded iodine overlay maps using iodine-related attenuation (in Hounsfield units) and iodine quantification (in milligrams per milliliter). For iodine-related attenuation the iodine uptake thresholds of 15 and 20 HU were tested; a threshold of 0.5 mg/mL was used for iodine quantification. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of iodine-related attenuation and iodine quantification were calculated from chi-square tests of contingency with histopathology or imaging follow-up as the reference standard. The 95% CIs were calculated from binomial expression. Differences in sensitivity and specificity were assessed by means of McNemar analysis. RESULTS: A significant difference in sensitivity and specificity was found between iodine-related attenuation with the thresholds of 15 HU (sensitivity, 91.4%; specificity, 93.3%; PPV, 91.4%; NPV, 93.3%) and 20 HU (sensitivity, 77.1%; specificity, 100%; PPV, 100%; NPV, 84.9%) (p = 0.008) and between iodine quantification (sensitivity, 100%; specificity, 97.7%; PPV, 97.2%; NPV, 100%) and iodine-related attenuation with a threshold of 20 HU (p = 0.004). No significant difference in sensitivity and specificity was found between iodine quantification and iodine-related attenuation with a threshold of 15 HU. CONCLUSION: Contrast-enhanced dual-energy MDCT with iodine-related attenuation and iodine quantification allows accurate evaluation of iodine uptake in renal lesions on a single-phase nephrographic image.

Authors
Mileto, A; Marin, D; Ramirez-Giraldo, JC; Scribano, E; Krauss, B; Mazziotti, S; Ascenti, G
MLA Citation
Mileto, A, Marin, D, Ramirez-Giraldo, JC, Scribano, E, Krauss, B, Mazziotti, S, and Ascenti, G. "Accuracy of contrast-enhanced dual-energy MDCT for the assessment of iodine uptake in renal lesions." AJR. American journal of roentgenology 202.5 (May 2014): W466-W474.
PMID
24758682
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
202
Issue
5
Publish Date
2014
Start Page
W466
End Page
W474
DOI
10.2214/ajr.13.11450

Focal lesions in cirrhotic liver: what else beyond hepatocellular carcinoma?

Detection and characterization of focal lesions in the cirrhotic liver may pose a diagnostic dilemma. Several benign and malignant lesions may be found in a cirrhotic liver along with hepatocellular carcinoma (HCC), and may exhibit typical or atypical imaging features. In this pictorial essay, we illustrate computed tomography and magnetic resonance imaging findings of lesions such as simple bile duct cysts, hemangioma, focal nodular hyperplasia-like nodules, peribiliary cysts, intrahepatic cholangiocarcinoma, lymphoma, and metastases, all of which occur in cirrhotic livers with varying prevalences. Pseudolesions, such as perfusion anomalies, focal confluent fibrosis, and segmental hyperplasia, will also be discussed. Imaging characterization of non-HCC lesions in cirrhosis is important in formulating an accurate diagnosis and triaging the patient towards the most appropriate management.

Authors
Galia, M; Taibbi, A; Marin, D; Furlan, A; Dioguardi Burgio, M; Agnello, F; Cabibbo, G; Van Beers, BE; Bartolotta, TV; Midiri, M; Lagalla, R; Brancatelli, G
MLA Citation
Galia, M, Taibbi, A, Marin, D, Furlan, A, Dioguardi Burgio, M, Agnello, F, Cabibbo, G, Van Beers, BE, Bartolotta, TV, Midiri, M, Lagalla, R, and Brancatelli, G. "Focal lesions in cirrhotic liver: what else beyond hepatocellular carcinoma?." Diagnostic and interventional radiology (Ankara, Turkey) 20.3 (May 2014): 222-228.
PMID
24509186
Source
epmc
Published In
Diagnostic and interventional radiology (Ankara, Turkey)
Volume
20
Issue
3
Publish Date
2014
Start Page
222
End Page
228
DOI
10.5152/dir.2014.13184

Dual energy MDCT assessment of renal lesions: an overview.

With the expansion of cross-sectional imaging, the number of renal lesions that are incidentally discovered has increased. Multidetector CT (MDCT) is the investigation of choice for characterising and staging renal lesions. Although a definitive diagnosis can be confidently posed for most of them, a number of renal lesions remain indeterminate following MDCT. Further imaging tests are therefore needed, with subsequent increase of healthcare costs, radiation exposure, and patient anxiety. By addressing most of the issues with conventional MDCT imaging, dual-energy MDCT can improve the diagnosis of renal lesions and, potentially, may represent a paradigm shift from a merely attenuation-based to a material-specific spectral imaging investigation. The purpose of this review is to provide an overview of current clinical applications of dual-energy CT in the evaluation of renal lesions. Key Points • As MDCT expands, an increasing number of renal lesions are serendipitously discovered. • With conventional MDCT, technical issues affect the diagnosis of renal lesions. • Dual-energy CT addresses some of the drawbacks of conventional MDCT. • Dual-energy CT may represent a paradigm shift for renal lesions imaging.

Authors
Mileto, A; Marin, D; Nelson, RC; Ascenti, G; Boll, DT
MLA Citation
Mileto, A, Marin, D, Nelson, RC, Ascenti, G, and Boll, DT. "Dual energy MDCT assessment of renal lesions: an overview." Eur Radiol 24.2 (February 2014): 353-362. (Review)
PMID
24092045
Source
pubmed
Published In
European Radiology
Volume
24
Issue
2
Publish Date
2014
Start Page
353
End Page
362
DOI
10.1007/s00330-013-3030-8

Hepatocellular carcinoma enhancement on contrast-enhanced CT and MR imaging: Response assessment after treatment with sorafenib: Preliminary results

Purpose: This study was undertaken to compare response evaluation criteria in solid tumours (RECIST) 1.1 and modified RECIST (mRECIST) in patients with unresectable hepatocellular carcinoma (HCC) on sorafenib, and to describe HCC enhancement changes before and after sorafenib treatment. Methods and materials: Seventeen patients (12 men, 5 women; mean age 69 years; age range 58-79 years) were included. Tumour response was assessed according to RECIST and mRECIST. Two readers placed a region of interest (ROI) within each target lesion, on the portion showing enhancement during the arterial phase. The lesion attenuation values measured within the ROIs on computed tomography or the signal intensity measured on magnetic resonance imaging, during the unenhanced phase, hepatic arterial phase and venous phase were recorded. Changes in arterial and venous contrast enhancement before and after treatment were compared among the mRECIST groups using Mann-Whitney U test. Results: Agreement between mRECIST and RECIST was good (Cohen's k coefficient, 0.791). Patients with partial response had a greater decrease in arterial enhancement (-79.8 %) than did patients with stable disease (SD) (-24.8 %; p = 0.011) or progressive disease (PD) (-32.9 %; p = 0.034). No statistically significant difference in arterial enhancement variation was found among patients with SD and PD. No statistically significant difference in venous enhancement was found among the mRECIST groups. Conclusions: mRECIST showed a more favourable response compared to RECIST 1.1 in patients with unresectable HCC receiving sorafenib. © 2013 Italian Society of Medical Radiology.

Authors
Salvaggio, G; Furlan, A; Agnello, F; Cabibbo, G; Marin, D; Giannitrapani, L; Genco, C; Midiri, M; Lagalla, R; Brancatelli, G
MLA Citation
Salvaggio, G, Furlan, A, Agnello, F, Cabibbo, G, Marin, D, Giannitrapani, L, Genco, C, Midiri, M, Lagalla, R, and Brancatelli, G. "Hepatocellular carcinoma enhancement on contrast-enhanced CT and MR imaging: Response assessment after treatment with sorafenib: Preliminary results." Radiologia Medica 119.4 (January 1, 2014): 215-221.
Source
scopus
Published In
La Radiologia Medica
Volume
119
Issue
4
Publish Date
2014
Start Page
215
End Page
221
DOI
10.1007/s11547-013-0332-5

Vascular artifact mimicking thrombosis on mr imaging using ferumoxytol as a contrast agent in abdominal vascular assessment

Purpose To describe an artifact that mimics thrombosis when assessing abdominal vasculature on magnetic resonance (MR) imaging using ferumoxytol in patients with contraindications to gadolinium-based contrast agents and to evaluate factors that may contribute to this artifact. Materials and Methods Three radiologists in consensus retrospectively evaluated 61 abdominal MR imaging examinations using ferumoxytol as an intravenous contrast agent for the presence of an observed artifact that can mimic thrombosis. Patient demographics and contrast agent bolus concentrations were compared with an unpaired Wilcoxon signed rank test. Results An artifact mimicking thrombosis was observed in 30 of 61 examinations, all on the arterial phase sequences. In examinations with this artifact, the average concentration of administered ferumoxytol was greater than in examinations where the artifact was not observed (P <.01). Several additional vascular findings were observed, including portal vein thrombosis (n = 2) and aneurysm (n = 1), renal vein thrombosis (n = 2), abdominal aortic aneurysm (n = 1), abdominal and iliac artery dissection (n = 3), and sequelae of portal hypertension (n = 8). Conclusions Although MR imaging using ferumoxytol as an intravenous contrast agent can be useful in detecting abdominal vascular abnormalities, an artifact mimicking vascular thrombosis was observed in nearly half of the examinations. © 2014 SIR.

Authors
Fananapazir, G; Marin, D; Suhocki, PV; Kim, CY; Bashir, MR
MLA Citation
Fananapazir, G, Marin, D, Suhocki, PV, Kim, CY, and Bashir, MR. "Vascular artifact mimicking thrombosis on mr imaging using ferumoxytol as a contrast agent in abdominal vascular assessment." Journal of Vascular and Interventional Radiology 25.6 (January 1, 2014): 969-976.
Source
scopus
Published In
JVIR: Journal of Vascular and Interventional Radiology
Volume
25
Issue
6
Publish Date
2014
Start Page
969
End Page
976
DOI
10.1016/j.jvir.2013.12.019

Interdependencies of acquisition, detection, and reconstruction techniques on the accuracy of iodine quantification in varying patient sizes employing dual-energy CT

© 2014, European Society of Radiology.Purpose: To assess the impact of patient habitus, acquisition parameters, detector efficiencies, and reconstruction techniques on the accuracy of iodine quantification using dual-source dual-energy CT (DECT). Materials and methods: Two phantoms simulating small and large patients contained 20 iodine solutions mimicking vascular and parenchymal enhancement from saline isodensity to 400 HU and 30 iodine solutions simulating enhancement of the urinary collecting system from 400 to 2,000 HU. DECT acquisition (80/140 kVp and 100/140 kVp) was performed using two DECT systems equipped with standard and integrated electronics detector technologies. DECT raw datasets were reconstructed using filtered backprojection (FBP), and iterative reconstruction (SAFIRE I/V). Results: Accuracy for iodine quantification was significantly higher for the small compared to the large phantoms (9.2 % ± 7.5 vs. 24.3 % ± 26.1, P = 0.0001), the integrated compared to the conventional detectors (14.8 % ± 20.6 vs. 18.8 % ± 20.4, respectively; P = 0.006), and SAFIRE V compared to SAFIRE I and FBP reconstructions (15.2 % ± 18.1 vs. 16.1 % ± 17.6 and 18.9 % ± 20.4, respectively; P ≤ 0.003). A significant synergism was observed when the most effective detector and reconstruction techniques were combined with habitus-adapted dual-energy pairs. Conclusion: In a second-generation dual-source DECT system, the accuracy of iodine quantification can be substantially improved by an optimal choice and combination of acquisition parameters, detector, and reconstruction techniques. Key Points: • Iodine quantification techniques are not immune to error • Systematic deviations between the measured and true iodine concentrations exist • Acquisition parameters, detector efficiencies, and reconstruction techniques impact accuracy of iodine quantification.

Authors
Marin, D; Pratts-Emanuelli, JJ; Mileto, A; Husarik, DB; Bashir, MR; Nelson, RC; Boll, DT
MLA Citation
Marin, D, Pratts-Emanuelli, JJ, Mileto, A, Husarik, DB, Bashir, MR, Nelson, RC, and Boll, DT. "Interdependencies of acquisition, detection, and reconstruction techniques on the accuracy of iodine quantification in varying patient sizes employing dual-energy CT." European Radiology 25.3 (January 1, 2014): 679-686.
Source
scopus
Published In
European Radiology
Volume
25
Issue
3
Publish Date
2014
Start Page
679
End Page
686
DOI
10.1007/s00330-014-3447-8

Multimodality approach to detection and characterization of hepatic hemangiomas

© Springer Science+Business Media New York 2014.Hemangiomas are the most common benign hepatic tumor and represent a common incidental finding on routine imaging examinations of the liver. The majority of hemangiomas demonstrate classical imaging findings on grayscale ultrasound (US), multidetector-row computed tomography (MDCT), and magnetic resonance imaging (MRI). The classic appearance on contrast-enhanced cross-sectional imaging is that of centripetal nodular enhancement with progressive fill-in of the lesion over time with conventional extracellular CT and MR contrast agents. With the advent of new gadolinium-based MR contrast agents such as hepatocyte-specific contrast agents and blood pool contrast agents, some different appearances of hemangiomas are possible and familiarity with these appearances is critical in making the correct diagnosis. There are also variants of the typical hemangioma, including the flash-filling hemangioma, giant hemangioma, sclerosed or hyalinized hemangioma, as well as hemangiomas occurring on a background of hepatic steatosis and cirrhosis. Again, knowledge of these variant types of hemangiomas can prevent against misdiagnosis of these lesions in the clinical setting.

Authors
Gupta, RT; Marin, D
MLA Citation
Gupta, RT, and Marin, D. "Multimodality approach to detection and characterization of hepatic hemangiomas." Abdomen and Thoracic Imaging: An Engineering and Clinical Perspective. January 1, 2014. 123-144.
Source
scopus
Publish Date
2014
Start Page
123
End Page
144
DOI
10.1007/978-1-4614-8498-1_5

Computer-aided liver volumetry: performance of a fully-automated, prototype post-processing solution for whole-organ and lobar segmentation based on MDCT imaging

© 2014, Springer Science+Business Media New York.Purpose: To evaluate the performance of a prototype, fully-automated post-processing solution for whole-liver and lobar segmentation based on MDCT datasets. Materials and methods: A polymer liver phantom was used to assess accuracy of post-processing applications comparing phantom volumes determined via Archimedes’ principle with MDCT segmented datasets. For the IRB-approved, HIPAA-compliant study, 25 patients were enrolled. Volumetry performance compared the manual approach with the automated prototype, assessing intraobserver variability, and interclass correlation for whole-organ and lobar segmentation using ANOVA comparison. Fidelity of segmentation was evaluated qualitatively. Results: Phantom volume was 1581.0 ± 44.7 mL, manually segmented datasets estimated 1628.0 ± 47.8 mL, representing a mean overestimation of 3.0%, automatically segmented datasets estimated 1601.9 ± 0 mL, representing a mean overestimation of 1.3%. Whole-liver and segmental volumetry demonstrated no significant intraobserver variability for neither manual nor automated measurements. For whole-liver volumetry, automated measurement repetitions resulted in identical values; reproducible whole-organ volumetry was also achieved with manual segmentation, p<inf>ANOVA</inf> 0.98. For lobar volumetry, automated segmentation improved reproducibility over manual approach, without significant measurement differences for either methodology, p<inf>ANOVA</inf> 0.95–0.99. Whole-organ and lobar segmentation results from manual and automated segmentation showed no significant differences, p<inf>ANOVA</inf> 0.96–1.00. Assessment of segmentation fidelity found that segments I–IV/VI showed greater segmentation inaccuracies compared to the remaining right hepatic lobe segments. Conclusion: Automated whole-liver segmentation showed non-inferiority of fully-automated whole-liver segmentation compared to manual approaches with improved reproducibility and post-processing duration; automated dual-seed lobar segmentation showed slight tendencies for underestimating the right hepatic lobe volume and greater variability in edge detection for the left hepatic lobe compared to manual segmentation.

Authors
Fananapazir, G; Bashir, MR; Marin, D; Boll, DT
MLA Citation
Fananapazir, G, Bashir, MR, Marin, D, and Boll, DT. "Computer-aided liver volumetry: performance of a fully-automated, prototype post-processing solution for whole-organ and lobar segmentation based on MDCT imaging." Abdominal Imaging 40.5 (2014): 1203-1212.
Source
scival
Published In
Abdominal Imaging
Volume
40
Issue
5
Publish Date
2014
Start Page
1203
End Page
1212
DOI
10.1007/s00261-014-0276-9

Clinical impact of an adaptive statistical iterative reconstruction algorithm for detection of hypervascular liver tumours using a low tube voltage, high tube current MDCT technique

Objectives: To investigate the impact of an adaptive statistical iterative reconstruction (ASiR) algorithm on diagnostic accuracy and confidence for the diagnosis of hypervascular liver tumours, as well as the reader's perception of image quality, using a low tube voltage (80 kVp), high tube current computed tomography (CT) technique. Methods: Forty patients (29 men, 11 women) with 65 hypervascular liver tumours underwent dual energy CT. The 80 kV set of the dual energy acquisition was reconstructed with standard filtered backprojection (FBP) and ASiR at different blending levels. Lesion contrast-to-noise ratio (CNR), reader's confidence for lesion detection and characterisation, and reader's evaluation of image quality were recorded. Results: ASiR yielded significantly higher CNR values compared with FBP (P < 0.0001 for all comparisons). Reader's perception of lesion conspicuity and confidence in the diagnosis of malignancy were also higher with 60 % and 80 % ASiR, compared with FBP (P = 0.01 and < 0.001, respectively). Compared with FBP, ASiR yielded nearly significantly lower specificity for lesion detection and a substantial decrease in the reader's perception of image quality. Conclusions: Compared with the standard FBP algorithm, ASiR significantly improves conspicuity of hypervascular liver lesions. This improvement may come at the cost of decreased specificity and reader's perception of image quality. Key Points: • Adaptive statistical iterative reconstruction algorithms (ASiRs) offer increasing potential in multidetector CT. • An ASiR algorithm significantly improves conspicuity of hypervascular liver lesions at MDCT. • Improved lesion conspicuity translates into increased reader's confidence for diagnosis of malignancy. • False positive findings may increase with ASiR, leading to potentially lower specificity. © 2013 European Society of Radiology.

Authors
Marin, D; Choudhury, KR; Gupta, RT; Ho, LM; Allen, BC; Schindera, ST; Colsher, JG; Samei, E; Nelson, RC
MLA Citation
Marin, D, Choudhury, KR, Gupta, RT, Ho, LM, Allen, BC, Schindera, ST, Colsher, JG, Samei, E, and Nelson, RC. "Clinical impact of an adaptive statistical iterative reconstruction algorithm for detection of hypervascular liver tumours using a low tube voltage, high tube current MDCT technique." European Radiology 23.12 (December 1, 2013): 3325-3335.
Source
scopus
Published In
European Radiology
Volume
23
Issue
12
Publish Date
2013
Start Page
3325
End Page
3335
DOI
10.1007/s00330-013-2964-1

Clinical impact of an adaptive statistical iterative reconstruction algorithm for detection of hypervascular liver tumours using a low tube voltage, high tube current MDCT technique.

OBJECTIVES: To investigate the impact of an adaptive statistical iterative reconstruction (ASiR) algorithm on diagnostic accuracy and confidence for the diagnosis of hypervascular liver tumours, as well as the reader's perception of image quality, using a low tube voltage (80 kVp), high tube current computed tomography (CT) technique. METHODS: Forty patients (29 men, 11 women) with 65 hypervascular liver tumours underwent dual energy CT. The 80 kV set of the dual energy acquisition was reconstructed with standard filtered backprojection (FBP) and ASiR at different blending levels. Lesion contrast-to-noise ratio (CNR), reader's confidence for lesion detection and characterisation, and reader's evaluation of image quality were recorded. RESULTS: ASiR yielded significantly higher CNR values compared with FBP (P < 0.0001 for all comparisons). Reader's perception of lesion conspicuity and confidence in the diagnosis of malignancy were also higher with 60 % and 80 % ASiR, compared with FBP (P = 0.01 and < 0.001, respectively). Compared with FBP, ASiR yielded nearly significantly lower specificity for lesion detection and a substantial decrease in the reader's perception of image quality. CONCLUSIONS: Compared with the standard FBP algorithm, ASiR significantly improves conspicuity of hypervascular liver lesions. This improvement may come at the cost of decreased specificity and reader's perception of image quality.

Authors
Marin, D; Choudhury, KR; Gupta, RT; Ho, LM; Allen, BC; Schindera, ST; Colsher, JG; Samei, E; Nelson, RC
MLA Citation
Marin, D, Choudhury, KR, Gupta, RT, Ho, LM, Allen, BC, Schindera, ST, Colsher, JG, Samei, E, and Nelson, RC. "Clinical impact of an adaptive statistical iterative reconstruction algorithm for detection of hypervascular liver tumours using a low tube voltage, high tube current MDCT technique." Eur Radiol 23.12 (December 2013): 3325-3335.
PMID
23832320
Source
pubmed
Published In
European Radiology
Volume
23
Issue
12
Publish Date
2013
Start Page
3325
End Page
3335
DOI
10.1007/s00330-013-2964-1

Cirrhosis

© 2013 Springer-Verlag Berlin Heidelberg. All rights are reserved.Cirrhosis is a pathologic and clinical entity that occurs following repeated hepatocyte damage and is characterized by extensive fibrosis and innumerable regenerative nodules replacing the normal liver parenchyma. Ultimately, the process can lead to liver failure.

Authors
Marin, D; Nelson, R
MLA Citation
Marin, D, and Nelson, R. "Cirrhosis." Abdominal Imaging. November 1, 2013. 1013-1026.
Source
scopus
Publish Date
2013
Start Page
1013
End Page
1026
DOI
10.1007/978-3-642-13327-5_78

FDG-PET/CT characterization of adrenal nodules: diagnostic accuracy and interreader agreement using quantitative and qualitative methods.

PURPOSE: To determine interreader agreement and diagnostic accuracy across varying levels of reader experience using qualitative and quantitative methods of evaluating adrenal nodules using ((18)F)-fluorodeoxyglucose-positron emission tomography/computed tomography. METHODS: 132 adrenal nodules (96 adenomas, 36 metastases) were retrospectively identified in 105 patients (49 men and 56 women, mean age 66 years, age range 45-85 years) with a history of lung cancer who underwent ((18)F)-fluorodeoxyglucose-positron emission tomography/computed tomography. For each nodule, three readers independently performed one qualitative and two quantitative measurements: visual assessment, standardized uptake value (SUVmax), and standard uptake ratio (SUVratio). Interreader agreement was calculated using percent agreement with κ statistic for qualitative analysis and intraclass correlation coefficient (ICC) for quantitative analysis. Accuracy, sensitivity, and specificity for distinguishing benign from malignant adrenal nodules were calculated for each method. RESULTS: Percent agreement between readers for visual (qualitative) assessment was 92% to 96% and κ statistic was 0.79 to 0.90 (95% confidence limits 0.66-0.99). ICC for SUVmax was 92% to 99% (95% CL 0.8-1.0), and ICC for SUVratio was 89% to 99% (95% CL 0.74-0.99). For diagnosis of malignancy, mean sensitivity and specificity for visual assessment were 80% and 97%, respectively. Mean sensitivity and specificity for SUVmax were 91% and 81%, respectively; for SUVratio, 90% and 80%. Mean diagnostic accuracy was 93%, 83%, and 84% for visual assessment, SUVmax, and SUVratio, respectively. CONCLUSION: Excellent interreader agreement is seen for quantitative and qualitative methods of distinguishing benign from malignant adrenal nodules. Qualitative analysis demonstrated higher accuracy but lower sensitivity compared with quantitative analysis.

Authors
Evans, PD; Miller, CM; Marin, D; Stinnett, SS; Wong, TZ; Paulson, EK; Ho, LM
MLA Citation
Evans, PD, Miller, CM, Marin, D, Stinnett, SS, Wong, TZ, Paulson, EK, and Ho, LM. "FDG-PET/CT characterization of adrenal nodules: diagnostic accuracy and interreader agreement using quantitative and qualitative methods." Acad Radiol 20.8 (August 2013): 923-929.
PMID
23830599
Source
pubmed
Published In
Academic Radiology
Volume
20
Issue
8
Publish Date
2013
Start Page
923
End Page
929
DOI
10.1016/j.acra.2013.02.010

Pancreas

© Springer-Verlag Italia 2014. All rights reserved.Imaging of the pancreas is challenging because of its anatomic location in the retroperitoneum and its intricate relationship with major blood vessels and bowel [1]. In the United States, acute pancreatitis, chronic pancreatitis, and pancreatic cancer are the most common pancreatic disorders [2]. Gallstone disease, which is strongly associated with obesity and the excessive consumption of alcohol, is the major risk factor for benign pancreatic disease, whereas smoking is the most important risk factor for pancreatic cancer [2].

Authors
Mileto, A; Marin, D; Nelson, RC
MLA Citation
Mileto, A, Marin, D, and Nelson, RC. "Pancreas." CT of the Retroperitoneum: From Conventional to Multi-energy Imaging. May 1, 2013. 83-100.
Source
scopus
Publish Date
2013
Start Page
83
End Page
100
DOI
10.1007/978-88-470-5469-1-7

Precision of iodine quantification in hepatic CT: effects of iterative reconstruction with various imaging parameters.

OBJECTIVE: The objective of this study was to evaluate the feasibility of using iterative reconstructions in hepatic CT to improve the precision of Hounsfield unit quantification, which is the degree to which repeated measurements under unchanged conditions provide consistent results. MATERIALS AND METHODS: An anthropomorphic liver phantom with iodinated lesions designed to simulate the enhancement of hypervascular tumors during the late hepatic arterial phase was imaged, and images were reconstructed with both filtered back projection (FBP) and iterative reconstructions, such as adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR). This protocol was further expanded into various dose levels, tube voltages, and slice thicknesses to investigate the effect of iterative reconstructions under all these conditions. The iodine concentrations of the lesions were quantified, with their precision calculated in terms of repeatability coefficient. RESULTS: ASIR reduced image noise by approximately 35%, and improved the quantitative precision by approximately 5%, compared with FBP. MBIR reduced noise by more than 65% and improved the precision by approximately 25% compared with the routine protocol. MBIR consistently showed better precision across a thinner slice thickness, lower tube voltage, and larger patient, achieving the target precision level at a dose lower (≥ 40%) than that of FBP. CONCLUSION: ASIR blended with 50% of FBP indicated a moderate gain in quantitative precision compared with FBP but could achieve more with a higher percentage. A higher gain was achieved by MBIR. These findings may be used to reduce the dose required for reliable quantification and may further serve as a basis for protocol optimization in terms of iodine quantification.

Authors
Chen, B; Marin, D; Richard, S; Husarik, D; Nelson, R; Samei, E
MLA Citation
Chen, B, Marin, D, Richard, S, Husarik, D, Nelson, R, and Samei, E. "Precision of iodine quantification in hepatic CT: effects of iterative reconstruction with various imaging parameters." AJR. American journal of roentgenology 200.5 (May 2013): W475-W482.
PMID
23617515
Source
epmc
Published In
AJR. American journal of roentgenology
Volume
200
Issue
5
Publish Date
2013
Start Page
W475
End Page
W482
DOI
10.2214/ajr.12.9658

Adrenal lesions: spectrum of imaging findings with emphasis on multi-detector computed tomography and magnetic resonance imaging.

The adrenal gland is a common site of a large spectrum of abnormalities like primary tumors, hemorrhage, metastases, and enlargement of the gland from external hormonal stimulation. Most of these lesions represent nonfunctioning adrenal adenomas and thus warrant a conservative management. Multi-detector computed tomography (CT) and magnetic resonance (MR) imaging are still considered highly specific and complementary techniques for the detection and characterization of adrenal abnormalities. Radiologist can establish a definitive diagnosis for most adrenal masses (i.e., carcinoma, hemorrhage) based on imaging alone. Imaging therefore can differentiate malignant lesions from those benign and avoid unnecessary aggressive management of benign lesions. The article gives an overview of the adrenal lesions and their imaging characteristics seen on CT and MR imaging.

Authors
Guerrisi, A; Marin, D; Baski, M; Guerrisi, P; Capozza, F; Catalano, C
MLA Citation
Guerrisi, A, Marin, D, Baski, M, Guerrisi, P, Capozza, F, and Catalano, C. "Adrenal lesions: spectrum of imaging findings with emphasis on multi-detector computed tomography and magnetic resonance imaging." Journal of clinical imaging science 3 (January 2013): 61-.
PMID
24605256
Source
epmc
Published In
Journal of Clinical Imaging Science
Volume
3
Publish Date
2013
Start Page
61
DOI
10.4103/2156-7514.124088

Hepatocellular carcinoma enhancement on contrast-enhanced CT and MR imaging: response assessment after treatment with sorafenib: preliminary results

Authors
Salvaggio, G; Furlan, A; Agnello, F; Cabibbo, G; Marin, D; Giannitrapani, L; Genco, C; Midiri, M; Lagalla, R; Brancatelli, G
MLA Citation
Salvaggio, G, Furlan, A, Agnello, F, Cabibbo, G, Marin, D, Giannitrapani, L, Genco, C, Midiri, M, Lagalla, R, and Brancatelli, G. "Hepatocellular carcinoma enhancement on contrast-enhanced CT and MR imaging: response assessment after treatment with sorafenib: preliminary results." Radiologia Medica (2013): 1-7.
PMID
24297581
Source
scopus
Published In
La Radiologia Medica
Publish Date
2013
Start Page
1
End Page
7

Dual-energy CT applications in the abdomen.

OBJECTIVE: The purpose of this article is to give a brief overview of the technical background of dual-energy CT (DECT) imaging and to review various DECT applications in the abdomen that are currently available for clinical practice. In a review of the recent literature, specific DECT applications available for abdominal organs, liver, pancreas, kidneys including renal stones, and adrenal glands, will be discussed in light of reliability and clinical usefulness in replacing true unenhanced imaging, increased lesion conspicuity, iodine extraction, and improved tissue/material characterization (e.g., renal stone composition). Radiation dose considerations will be addressed in comparison with standard abdominal imaging protocols. CONCLUSION: Modern DECT applications for the abdomen expand the use of CT and enable advanced quantitative methods in the clinical routine on the basis of differences in material attenuation observed by imaging at two different distinct photon energies.

Authors
Heye, T; Nelson, RC; Ho, LM; Marin, D; Boll, DT
MLA Citation
Heye, T, Nelson, RC, Ho, LM, Marin, D, and Boll, DT. "Dual-energy CT applications in the abdomen." AJR Am J Roentgenol 199.5 Suppl (November 2012): S64-S70. (Review)
PMID
23097169
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
199
Issue
5 Suppl
Publish Date
2012
Start Page
S64
End Page
S70
DOI
10.2214/AJR.12.9196

Hepatic hemangiomas: difference in enhancement pattern on 3T MR imaging with gadobenate dimeglumine versus gadoxetate disodium.

PURPOSE: To compare intraindividual differences in enhancement pattern of hepatic hemangiomas between gadobenate dimeglumine (Gd-BOPTA) and gadoxetate disodium (Gd-EOB-DTPA)-enhanced 3T MR imaging. MATERIALS AND METHODS: This is a HIPAA-compliant, IRB-approved retrospective study with waiver for informed consent granted. From 10/07 to 5/09, 10 patients (2 males, 8 females; mean age, 57.3 years) with 15 hepatic hemangiomas (mean diameter, 4.4 ± 5.6 cm) underwent both Gd-BOPTA- and Gd-EOB-DTPA-enhanced 3T MR imaging (mean interval, 266 days; range, 38-462 days). Diagnosis of hemangioma was based on strict imaging criteria. MR imaging was obtained during three arterial, portal venous, and up to four delayed phases. During each phase, hemangioma-to-liver contrast-to-noise ratio (CNR) was measured for each lesion on both examinations. Statistical analysis was performed using paired Student's t-test. RESULTS: Hemangioma-to-liver CNR peaked during the portal venous phase (Gd-BOPTA: 48.9 ± 65.8, Gd-EOB-DTPA: 0.7 ± 3.8). During all imaging phases except the first arterial phase, hemangioma-to-liver CNR was significantly lower on Gd-EOB-DTPA-enhanced compared to Gd-BOPTA-enhanced MR images (p<0.05). Notably, Gd-EOB-DTPA yielded negative hemangioma-to-liver CNR (-2.5 ± 2.4) compared to Gd-BOPTA (40.7 ± 56.4) during the first delayed phase (7-8 min after contrast administration), remaining negative for the rest of the delayed phases (up to 26 min after contrast administration). CONCLUSION: The enhancement patterns of hepatic hemangiomas differs significantly between Gd-BOPTA and Gd-EOB-DTPA-enhanced 3T MR imaging. The smaller dose, shorter plasma half-life, and increased hepatobiliary uptake of Gd-EOB-DTPA leads to a negative CNR of hemangioma-to-liver on delayed phases and could create an imaging pitfall with this agent.

Authors
Gupta, RT; Marin, D; Boll, DT; Husarik, DB; Davis, DE; Feuerlein, S; Merkle, EM
MLA Citation
Gupta, RT, Marin, D, Boll, DT, Husarik, DB, Davis, DE, Feuerlein, S, and Merkle, EM. "Hepatic hemangiomas: difference in enhancement pattern on 3T MR imaging with gadobenate dimeglumine versus gadoxetate disodium." Eur J Radiol 81.10 (October 2012): 2457-2462.
PMID
22138122
Source
pubmed
Published In
European Journal of Radiology
Volume
81
Issue
10
Publish Date
2012
Start Page
2457
End Page
2462
DOI
10.1016/j.ejrad.2011.10.014

Radiation dose reduction in abdominal computed tomography during the late hepatic arterial phase using a model-based iterative reconstruction algorithm: how low can we go?

OBJECTIVE: The aim of this study was to compare the image quality of abdominal computed tomography scans in an anthropomorphic phantom acquired at different radiation dose levels where each raw data set is reconstructed with both a standard convolution filtered back projection (FBP) and a full model-based iterative reconstruction (MBIR) algorithm. MATERIALS AND METHODS: An anthropomorphic phantom in 3 sizes was used with a custom-built liver insert simulating late hepatic arterial enhancement and containing hypervascular liver lesions of various sizes. Imaging was performed on a 64-section multidetector-row computed tomography scanner (Discovery CT750 HD; GE Healthcare, Waukesha, WI) at 3 different tube voltages for each patient size and 5 incrementally decreasing tube current-time products for each tube voltage. Quantitative analysis consisted of contrast-to-noise ratio calculations and image noise assessment. Qualitative image analysis was performed by 3 independent radiologists rating subjective image quality and lesion conspicuity. RESULTS: Contrast-to-noise ratio was significantly higher and mean image noise was significantly lower on MBIR images than on FBP images in all patient sizes, at all tube voltage settings, and all radiation dose levels (P < 0.05). Overall image quality and lesion conspicuity were rated higher for MBIR images compared with FBP images at all radiation dose levels. Image quality and lesion conspicuity on 25% to 50% dose MBIR images were rated equal to full-dose FBP images. CONCLUSION: This phantom study suggests that depending on patient size, clinically acceptable image quality of the liver in the late hepatic arterial phase can be achieved with MBIR at approximately 50% lower radiation dose compared with FBP.

Authors
Husarik, DB; Marin, D; Samei, E; Richard, S; Chen, B; Jaffe, TA; Bashir, MR; Nelson, RC
MLA Citation
Husarik, DB, Marin, D, Samei, E, Richard, S, Chen, B, Jaffe, TA, Bashir, MR, and Nelson, RC. "Radiation dose reduction in abdominal computed tomography during the late hepatic arterial phase using a model-based iterative reconstruction algorithm: how low can we go?." Invest Radiol 47.8 (August 2012): 468-474.
PMID
22717881
Source
pubmed
Published In
Investigative Radiology
Volume
47
Issue
8
Publish Date
2012
Start Page
468
End Page
474
DOI
10.1097/RLI.0b013e318251eafd

Characterization of adrenal nodules with dual-energy CT: can virtual unenhanced attenuation values replace true unenhanced attenuation values?

OBJECTIVE: The purpose of our study was to investigate whether virtual unenhanced adrenal nodule attenuation values can replace true noncontrast attenuation values. MATERIALS AND METHODS: Twenty-three incidentally discovered adrenal nodules (19 adenomas and four metastases) were identified in 19 patients (11 men and eight women; mean age, 65 years; age range, 38-84 years) who underwent unenhanced single-energy CT followed by contrast-enhanced dual-energy CT on the same scanner. A virtual unenhanced imaging dataset was generated from each dual-energy CT dataset. CT attenuation of each adrenal nodule was measured at the same location on virtual unenhanced images and true unenhanced images by three radiologists and mean values compared using the Student t test. Correlation between virtual unenhanced and true unenhanced values was determined using linear regression analysis. The mean difference and percentage of diagnostic agreement were also determined. Interreader variability was assessed using the intraclass correlation coefficient (ICC). RESULTS: The mean ± SD attenuation values for virtual unenhanced images and true unenhanced images were 14.7 ± 15.1 HU and 12.9 ± 13.4 HU, respectively (p = 0.2). Strong positive correlation was observed between virtual unenhanced images and true unenhanced images (R = 0.83-0.87). The mean difference between virtual unenhanced images and true unenhanced images was 1.8 ± 1.7 HU. Diagnostic agreement between virtual unenhanced images and true unenhanced images was 83-91% for three radiologists. No malignant nodules were misclassified as benign on virtual unenhanced images. The ICC was 0.88 and 0.96 for virtual unenhanced images and true unenhanced images, respectively, indicating high interreader agreement. CONCLUSION: Virtual unenhanced and true unenhanced attenuation measurements of adrenal nodules were not significantly different and showed strongly positive linear correlation. This finding resulted in substantial diagnostic agreement between virtual unenhanced images and true unenhanced images for distinguishing benign from malignant nodules.

Authors
Ho, LM; Marin, D; Neville, AM; Barnhart, HX; Gupta, RT; Paulson, EK; Boll, DT
MLA Citation
Ho, LM, Marin, D, Neville, AM, Barnhart, HX, Gupta, RT, Paulson, EK, and Boll, DT. "Characterization of adrenal nodules with dual-energy CT: can virtual unenhanced attenuation values replace true unenhanced attenuation values?." AJR Am J Roentgenol 198.4 (April 2012): 840-845.
PMID
22451549
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
198
Issue
4
Publish Date
2012
Start Page
840
End Page
845
DOI
10.2214/AJR.11.7316

Gastrointestinal imaging

Authors
Nelson, RC; Low, VHS; Hough, DM; Paulson, EK; Seabourn, JT; Freed, KS; Kerner, ML; Keogan, MT; Marin, D; Suhocki, PV
MLA Citation
Nelson, RC, Low, VHS, Hough, DM, Paulson, EK, Seabourn, JT, Freed, KS, Kerner, ML, Keogan, MT, Marin, D, and Suhocki, PV. "Gastrointestinal imaging." Duke Radiology Case Review: Imaging, Differential Diagnosis, and Discussion: 2nd Edition. January 19, 2012. 111-.
Source
scopus
Publish Date
2012
Start Page
111

Effectiveness of a three-dimensional dual gradient echo two-point Dixon technique for the characterization of adrenal lesions at 3 Tesla.

OBJECTIVE: To compare the sensitivity, specificity, and diagnostic accuracy of fat-only datasets reconstructed using a two-point Dixon technique, with corresponding opposed-phase (OP) and in-phase (IP) datasets for characterization of adrenal lesions at 3 Tesla (T). METHODS: Fifty-nine patients (21 male, 38 female) with 66 adrenal lesions (49 adenomas, 17 nonadenomas) underwent 3D dual gradient-echo 3-T adrenal MR imaging with reconstruction of OP/IP and fat/water datasets. Sensitivity, specificity, and diagnostic accuracy were compared between OP/IP datasets, using the signal intensity index (SII), and fat/water datasets, using the fat fraction and fat ratio. Four radiologists qualitatively assessed OP/IP and fat-only datasets for reader confidence in lesion characterization and image quality. RESULTS: There were significant differences between adenomas and nonadenomas with regard to mean SII, fat fraction, and fat ratio (P < 0.001). There was no significant difference in mean diagnostic accuracy among different evaluation methods using OP/IP and fat/water datasets. Mean readers' scores for lesion characterization were significantly higher for adenomas than for nonadenomas using OP/IP and fat-only datasets. There was no significant difference between the two datasets regarding mean readers' scores for image quality. CONCLUSION: Fat-only images can readily differentiate adrenal adenomas from nonadenomas, with diagnostic accuracy comparable to OP/IP images.

Authors
Marin, D; Dale, BM; Bashir, MR; Ziemlewicz, TJ; Ringe, KI; Boll, DT; Merkle, EM
MLA Citation
Marin, D, Dale, BM, Bashir, MR, Ziemlewicz, TJ, Ringe, KI, Boll, DT, and Merkle, EM. "Effectiveness of a three-dimensional dual gradient echo two-point Dixon technique for the characterization of adrenal lesions at 3 Tesla." Eur Radiol 22.1 (January 2012): 259-268.
PMID
21874570
Source
pubmed
Published In
European Radiology
Volume
22
Issue
1
Publish Date
2012
Start Page
259
End Page
268
DOI
10.1007/s00330-011-2244-x

Enhancement pattern of small hepatocellular carcinoma (HCC) at contrast-enhanced US (CEUS), MDCT, and MRI: Intermodality agreement and comparison of diagnostic sensitivity between 2005 and 2010 American Association for the Study of Liver Diseases (AASLD) guidelines

Objective: To evaluate agreement between contrast-enhanced ultrasound (CEUS), multi-detector row computed tomography (MDCT) and magnetic resonance imaging (MRI) for the assessment of typical and atypical enhancement patterns of small hepatocellular carcinoma (HCC); and to compare diagnostic sensitivity of 2005 and 2010 American Association for the Study of Liver Diseases (AASLD) guidelines. Materials and methods: Between January 2008 and December 2009, we included cirrhotic patients with newly diagnosed 10-20 mm HCC imaged at two contrast-enhanced imaging techniques among CEUS, MDCT, and MRI. Dynamic studies were reviewed by two radiologists to assess enhancement pattern. Percentage of cases with concordant findings and Cohen coefficient (k) were calculated. McNemar's test was used to compare sensitivity between 2005 and 2010 AASLD guidelines. Results: There were 91 patients (69 M; 22 F; mean age, 68 years) with 96 HCCs, studied with a combination of CEUS and MDCT (n = 59), CEUS and MRI (n = 26), or MDCT and MRI (n = 11). Intermodality agreement for assessment of tumor enhancement pattern was 67% (k = 0.294, P = 0.001). Typical enhancement pattern was detected coincidentally at two imaging modalities in 50 (52%) HCCs. Sensitivity for the diagnosis of HCC increased significantly using the 2010 AASLD (81/96 (84%) vs. 50/96 (52%), P < 0.001). Conclusions: Agreement between two imaging modalities for the detection of typical tumor enhancement pattern was reached in 52% of cases. The 2010 AASLD guidelines significantly increased the sensitivity for the diagnosis of HCC. © 2011 Elsevier Ireland Ltd.

Authors
Furlan, A; Marin, D; Cabassa, P; Taibbi, A; Brunelli, E; Agnello, F; Lagalla, R; Brancatelli, G
MLA Citation
Furlan, A, Marin, D, Cabassa, P, Taibbi, A, Brunelli, E, Agnello, F, Lagalla, R, and Brancatelli, G. "Enhancement pattern of small hepatocellular carcinoma (HCC) at contrast-enhanced US (CEUS), MDCT, and MRI: Intermodality agreement and comparison of diagnostic sensitivity between 2005 and 2010 American Association for the Study of Liver Diseases (AASLD) guidelines." European Journal of Radiology 81.9 (2012): 2099-2105.
PMID
21906896
Source
scival
Published In
European Journal of Radiology
Volume
81
Issue
9
Publish Date
2012
Start Page
2099
End Page
2105
DOI
10.1016/j.ejrad.2011.07.010

Effect of tumor size and tumor-to-liver contrast of hypovascular liver tumors on the diagnostic performance of hepatic CT imaging.

To assess the effect of tumor size and tumor-to-liver contrast of simulated hypovascular liver tumors on the diagnostic accuracy of hepatic computed tomography (CT). This retrospective study was approved by the institutional review board, and informed consent was waived. A total of 153 simulated hypovascular liver tumors were embedded in 70 hepatic CT data sets that were acquired during the portal venous phase. The simulated tumors had 3 different diameters (6, 10, and 14 mm) and 3 different tumor-to-liver contrast values (20, 35, and 50 HU). There were also 30 hepatic CT data sets without liver tumors. Three radiologists independently performed tumor detection on the randomized 100 hepatic CT data sets. The lowest sensitivity was obtained for the 6-mm tumors with a tumor-to-liver contrast of 20 HU (4.1%), and the highest sensitivity was obtained for the 10- and 14-mm tumors with a tumor-to-liver contrast of 50 HU (100%). Increasing the contrast from 20 to 35 to 50 HU in the 6-mm tumors yielded a significant increase in sensitivity (4.1%, 48.8%, and 92.4%, respectively; P < 0.0001). The sensitivity for the 10- and 14-mm tumors also increased significantly as the tumor-to-liver contrast value increased from 20 to 35 HU (P < 0.01). However, no significant increase in sensitivity was seen for the 10- and 14-mm tumors as the tumor-to-liver contrast values increased from 35 to 50 HU (P = 0.733 and P = 1.0, respectively). Increasing the tumor-to-liver contrast from 20 to 35 HU results in a significant increase in the detection of hypovascular liver tumors ranging from 6 to 14 mm in diameter. Optimization of the tumor-to-liver contrast is necessary for improved detection of hypovascular liver tumors.

Authors
Schindera, ST; Hareter, LF; Raible, S; Torrente, JC; Rusch, O; Rosskopf, AB; Marin, D; Vock, P; Szucs-Farkas, Z
MLA Citation
Schindera, ST, Hareter, LF, Raible, S, Torrente, JC, Rusch, O, Rosskopf, AB, Marin, D, Vock, P, and Szucs-Farkas, Z. "Effect of tumor size and tumor-to-liver contrast of hypovascular liver tumors on the diagnostic performance of hepatic CT imaging." Investigative radiology 47.3 (2012): 197-201.
PMID
22233758
Source
scival
Published In
Investigative Radiology
Volume
47
Issue
3
Publish Date
2012
Start Page
197
End Page
201
DOI
10.1097/RLI.0b013e3182361dbe

Imaging findings of liver resection using a bipolar radiofrequency electrosurgical device - Initial observations

Objective: To assess contrast-enhanced US (CEUS), computed tomography (CT) and magnetic resonance (MR) imaging findings and serial changes of the treated area at follow-up in patients who underwent liver resection using a bipolar radiofrequency electrosurgical device. Methods: Imaging findings of 27 patients with resected hepatocellular carcinomas (HCCs) (n = 24) and metastases (n = 3) (mean size: 2.6 cm), were retrospectively evaluated. Two readers assessed: the (a) presence, (b) thickness, (c) shape and (d) echogenicity (CEUS)/attenuation (CT)/signal intensity (MR imaging) at coagulated site and the (e) presence of residual tumor of the bipolar radiofrequency electrosurgical device resection margin. Results: Follow-up was performed with either CT (n = 20) or MR imaging (n = 7) and repeated in 16 patients with CT (n = 7), MR imaging (n = 4), or both techniques (n = 5). Four patients also had a single CEUS examination. At first imaging follow-up a peripheral halo was depicted at resection site (100%). A fluid collection within the surgical area was found in 67% of patients. During the following imaging examinations a progressive involution of both findings was observed, respectively, in 81% and 62% of patients. Viable tissue was detected in three patients (11%). Conclusions: After liver resection with bipolar radiofrequency electrosurgical device successfully ablated tumor is demonstrated at imaging by an unenhancing partial linear peripheral halo, in most cases, surrounding a fluid collection reducing in size during follow-up. © 2011 Elsevier Ireland Ltd. All rights reserved.

Authors
Taibbi, A; Furlan, A; Sandonato, L; Bova, V; Galia, M; Marin, D; Cabibbo, G; Soresi, M; Bartolotta, TV; Midiri, M; Lagalla, R; Brancatelli, G
MLA Citation
Taibbi, A, Furlan, A, Sandonato, L, Bova, V, Galia, M, Marin, D, Cabibbo, G, Soresi, M, Bartolotta, TV, Midiri, M, Lagalla, R, and Brancatelli, G. "Imaging findings of liver resection using a bipolar radiofrequency electrosurgical device - Initial observations." European Journal of Radiology 81.4 (2012): 663-670.
PMID
21306849
Source
scival
Published In
European Journal of Radiology
Volume
81
Issue
4
Publish Date
2012
Start Page
663
End Page
670
DOI
10.1016/j.ejrad.2011.01.015

Effect of tumor size and tumor-to-liver contrast of hypovascular liver tumors on the diagnostic performance of hepatic CT imaging

OBJECTIVE: To assess the effect of tumor size and tumor-to-liver contrast of simulated hypovascular liver tumors on the diagnostic accuracy of hepatic computed tomography (CT). MATERIALS AND METHODS: This retrospective study was approved by the institutional review board, and informed consent was waived. A total of 153 simulated hypovascular liver tumors were embedded in 70 hepatic CT data sets that were acquired during the portal venous phase. The simulated tumors had 3 different diameters (6, 10, and 14 mm) and 3 different tumor-to-liver contrast values (20, 35, and 50 HU). There were also 30 hepatic CT data sets without liver tumors. Three radiologists independently performed tumor detection on the randomized 100 hepatic CT data sets. RESULTS: The lowest sensitivity was obtained for the 6-mm tumors with a tumor-to-liver contrast of 20 HU (4.1%), and the highest sensitivity was obtained for the 10- and 14-mm tumors with a tumor-to-liver contrast of 50 HU (100%). Increasing the contrast from 20 to 35 to 50 HU in the 6-mm tumors yielded a significant increase in sensitivity (4.1%, 48.8%, and 92.4%, respectively; P < 0.0001). The sensitivity for the 10- and 14-mm tumors also increased significantly as the tumor-to-liver contrast value increased from 20 to 35 HU (P < 0.01). However, no significant increase in sensitivity was seen for the 10- and 14-mm tumors as the tumor-to-liver contrast values increased from 35 to 50 HU (P = 0.733 and P = 1.0, respectively). CONCLUSIONS: Increasing the tumor-to-liver contrast from 20 to 35 HU results in a significant increase in the detection of hypovascular liver tumors ranging from 6 to 14 mm in diameter. Optimization of the tumor-to-liver contrast is necessary for improved detection of hypovascular liver tumors.

Authors
Schindera, ST; Hareter, LF; Raible, S; Torrente, JC; Rusch, O; Rosskopf, AB; Marin, D; Vock, P; Szucs-Farkas, Z
MLA Citation
Schindera, ST, Hareter, LF, Raible, S, Torrente, JC, Rusch, O, Rosskopf, AB, Marin, D, Vock, P, and Szucs-Farkas, Z. "Effect of tumor size and tumor-to-liver contrast of hypovascular liver tumors on the diagnostic performance of hepatic CT imaging." Investigative Radiology (2012).
Source
scival
Published In
Investigative Radiology
Publish Date
2012
DOI
10.1097/RLI.0b013e3182361dbe

Hepatocellular carcinoma presenting at contrast-enhanced multi-detector-row computed tomography or gadolinium-enhanced magnetic resonance imaging as a small (≤2 cm), indeterminate nodule: Growth rate and optimal interval time for imaging follow-up

OBJECTIVE: The objective of the study was to measure growth rate and to determine the optimal interval time for imaging follow-up of hepatocellular carcinomas (HCCs) presenting at multi-detector-row computed tomography (MDCT) or magnetic resonance imaging (MRI) as small, indeterminate lesions. METHODS: We included patients with cirrhosis with HCC initially presenting as indeterminate lesion of 2 cm or less at MDCT or MRI August 2005 to August 2009 and with available imaging follow-up. Measures of tumor growth included tumor volume doubling time (TVDT), tumor percentual diameter increase, and tumor percentual volume increase. RESULTS: We examined 48 patients (mean age, 64 years) with 69 HCCs. At index examination, mean (SD) maximum transverse diameter and volume of lesions were 1.2 (SD, 0.3) cm and 0.6 (SD, 0.7) cm, respectively. Median TVDT was 210 days. Tumors with follow-up longer than 365 days had significant increase in tumor percentual diameter increase and tumor percentual volume increase. CONCLUSIONS: Median TVDT of 210 days suggests extended follow-up of 6 months for small, indeterminate liver nodules detected at MDCT or MRI. Copyright © 2012 by Lippincott Williams & Wilkins.

Authors
Furlan, A; Marin, D; Agnello, F; Martino, MD; Marco, VD; Lagalla, R; Catalano, C; Brancatelli, G
MLA Citation
Furlan, A, Marin, D, Agnello, F, Martino, MD, Marco, VD, Lagalla, R, Catalano, C, and Brancatelli, G. "Hepatocellular carcinoma presenting at contrast-enhanced multi-detector-row computed tomography or gadolinium-enhanced magnetic resonance imaging as a small (≤2 cm), indeterminate nodule: Growth rate and optimal interval time for imaging follow-up." Journal of Computer Assisted Tomography 36.1 (2012): 20-25.
PMID
22261766
Source
scival
Published In
Journal of Computer Assisted Tomography
Volume
36
Issue
1
Publish Date
2012
Start Page
20
End Page
25
DOI
10.1097/RCT.0b013e31823ed462

Focal nodular hyperplasia-like lesions in patients with cavernous transformation of the portal vein: prevalence, MR findings and natural history.

PURPOSE: To retrospectively investigate the prevalence, MR findings, natural history, and association with other hepatic lesions of focal nodular hyperplasia (FNH)-like lesions in a cohort of consecutive patients with cavernous transformation of the portal vein (CTPV). MATERIALS AND METHODS: This retrospective IRB-approved study comprised 58 patients (32 men, 26 women; average age, 50 years) with CTPV who underwent liver MR imaging between 2000 and 2008. MR images were assessed by two radiologists in consensus for the presence of (a) FNH-like lesions and other liver lesions, and (b) other imaging findings. Patients were assigned to a stable or progressive clinical course based on lesion characteristics at follow-up. RESULTS: Twelve of 58 patients (21%) had 38 FNH-like lesions (average size, 1.3 cm). Common findings of FNH-like lesions were isointensity on T2-weighted images (82%), intense and homogeneous enhancement during the arterial phase, and lack of washout during the hepatic venous and interstitial phases (100%). FNH-like lesions were found with other benign liver lesions (1 hemangioma, 1 adenoma) in two patients. Three (25%) patients with FNH-like lesions showed a progressive clinical course. CONCLUSION: FNH-like lesions are commonly detected in patients with CTPV. Most lesions demonstrate benign imaging findings and stable clinical course.

Authors
Marin, D; Galluzzo, A; Plessier, A; Brancatelli, G; Valla, D; Vilgrain, V
MLA Citation
Marin, D, Galluzzo, A, Plessier, A, Brancatelli, G, Valla, D, and Vilgrain, V. "Focal nodular hyperplasia-like lesions in patients with cavernous transformation of the portal vein: prevalence, MR findings and natural history." Eur Radiol 21.10 (October 2011): 2074-2082.
PMID
21710271
Source
pubmed
Published In
European Radiology
Volume
21
Issue
10
Publish Date
2011
Start Page
2074
End Page
2082
DOI
10.1007/s00330-011-2161-z

64-section multidetector CT of the upper abdomen: optimization of a saline chaser injection protocol for improved vascular and parenchymal contrast enhancement.

OBJECTIVES: To prospectively investigate the effect of varying the injection flow rates of a saline chaser on vascular and parenchymal contrast enhancement during abdominal MDCT. METHODS: 100 consecutive patients were randomly assigned to four injection protocols. A fixed dose of contrast medium was administered followed by no saline (Protocol A) or 50 mL of saline at 2, 4, or 8 mL/s (Protocols B, C, and D). Peak, time-to-peak, and duration of 90% peak enhancement were determined for aorta, pancreas, and liver. RESULTS: Aortic peak enhancement was significantly higher for Protocol D (369.5 HU) compared with Protocols A and B (332.9 HU and 326.0 HU, respectively; P < 0.05). Pancreatic peak enhancement was significantly higher for Protocols C and D (110.6 HU and 110.9 HU, respectively) compared to Protocol A (92.5 HU; P < 0.05). Aortic and pancreatic time-to-peak enhancement occurred significantly later for Protocol D compared with Protocol A (42.8 s vs. 36.1 s [P < 0.001] and 49.7 s vs. 45.3 s [P = 0.003]). CONCLUSIONS: Injecting a saline chaser at high flow rates yields significantly higher peak aortic and pancreatic enhancement, with a slight longer time-to-peak enhancement.

Authors
Marin, D; Nelson, RC; Guerrisi, A; Barnhart, H; Schindera, ST; Passariello, R; Catalano, C
MLA Citation
Marin, D, Nelson, RC, Guerrisi, A, Barnhart, H, Schindera, ST, Passariello, R, and Catalano, C. "64-section multidetector CT of the upper abdomen: optimization of a saline chaser injection protocol for improved vascular and parenchymal contrast enhancement." Eur Radiol 21.9 (September 2011): 1938-1947.
PMID
21556911
Source
pubmed
Published In
European Radiology
Volume
21
Issue
9
Publish Date
2011
Start Page
1938
End Page
1947
DOI
10.1007/s00330-011-2139-x

Iterative reconstruction algorithm for abdominal multidetector CT at different tube voltages: assessment of diagnostic accuracy, image quality, and radiation dose in a phantom study.

PURPOSE: To assess the diagnostic accuracy, image quality, and radiation dose of an iterative reconstruction algorithm compared with a filtered back projection (FBP) algorithm for abdominal computed tomography (CT) at different tube voltages. MATERIALS AND METHODS: A custom liver phantom with 45 simulated hypovascular liver tumors (diameters of 5, 10, and 15 mm; tumor-to-liver contrast of 10, 25, and 50 HU) was placed in a cylindrical water container that mimicked an intermediate-sized patient. The phantom was scanned at 120, 100, and 80 kVp. The CT data sets were reconstructed with FBP and iterative reconstruction. The image noise was measured, and the contrast-to-noise ratio (CNR) of the tumors was calculated. The radiation dose was assessed with the volume CT dose index. Tumor detection was independently performed by three radiologists. Statistical analysis included analysis of variance. RESULTS: Compared with the FBP data set at 120 kVp, the iterative reconstruction data set collected at 100 kVp demonstrated significantly lower mean image noise (20.9 and 16.7 HU, respectively; P < .001) and greater mean CNRs for the simulated tumors (P < .001). The iterative reconstruction data set collected at 120 kVp yielded the highest sensitivity for tumor detection, while the FBP data set at 80 kVp yielded the lowest. The sensitivity for the iterative reconstruction data set at 100 kVp was comparable with that for the FBP data set at 120 kVp (79.3% and 74.9%, respectively; P > .99). The volume CT dose index decreased by 39.8% between the 120-kVp protocol and the 100-kVp protocol and by 70.3% between the 120-kVp protocol and the 80-kVp protocol. CONCLUSION: Results of this phantom study suggest that a 100-kVp abdominal CT protocol with an iterative reconstruction algorithm for simulated intermediate-sized patients increases the image quality and maintains the diagnostic accuracy at a reduced radiation dose when compared with a 120-kVp protocol with an FBP algorithm.

Authors
Schindera, ST; Diedrichsen, L; Müller, HC; Rusch, O; Marin, D; Schmidt, B; Raupach, R; Vock, P; Szucs-Farkas, Z
MLA Citation
Schindera, ST, Diedrichsen, L, Müller, HC, Rusch, O, Marin, D, Schmidt, B, Raupach, R, Vock, P, and Szucs-Farkas, Z. "Iterative reconstruction algorithm for abdominal multidetector CT at different tube voltages: assessment of diagnostic accuracy, image quality, and radiation dose in a phantom study." Radiology 260.2 (August 2011): 454-462.
PMID
21493795
Source
pubmed
Published In
Radiology
Volume
260
Issue
2
Publish Date
2011
Start Page
454
End Page
462
DOI
10.1148/radiol.11102217

Body CT: technical advances for improving safety.

OBJECTIVE: In this review, we attempt to address many of the issues that are related to ensuring patient benefit in body CT, balancing the use of ionizing radiation and iodinated contrast media. We attempt to not only summarize the literature but also make recommendations relevant to CT protocols, including the technical parameters of both the scanner and the associated contrast media. CONCLUSION: Although CT is a powerful tool that has transformed the practice of medicine, the benefits are accompanied by important risks. Radiologists must understand these risks and the strategies available to minimize them as well as the risks associated with contrast medium delivery in abdominal CT.

Authors
Marin, D; Nelson, RC; Rubin, GD; Schindera, ST
MLA Citation
Marin, D, Nelson, RC, Rubin, GD, and Schindera, ST. "Body CT: technical advances for improving safety." AJR Am J Roentgenol 197.1 (July 2011): 33-41. (Review)
PMID
21701008
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
197
Issue
1
Publish Date
2011
Start Page
33
End Page
41
DOI
10.2214/AJR.11.6755

Decreased detection of hypovascular liver tumors with MDCT in obese patients: a phantom study.

OBJECTIVE: The purpose of this article is to assess the impact of large patient size on the detection of hypovascular liver tumors with MDCT and the effect of a noise filter on image quality and lesion detection in obese patients. MATERIALS AND METHODS: A liver phantom with 45 hypovascular tumors (diameters of 5, 10, and 15 mm) was placed into two water containers mimicking intermediate and large patients. The containers were scanned with a 64-MDCT scanner. The CT dataset from the large phantom was postprocessed using a noise filter. The image noise was measured and the contrast-to-noise ratio (CNR) of the tumors was calculated. Tumor detection was independently performed by three radiologists in a blinded fashion. RESULTS: The application of the noise filter in the large phantom yielded a reduction of image noise by 42% (p < 0.0001). The CNR values of the tumors in the nonfiltered and filtered large phantom were lower than that in the intermediate phantom (p < 0.05). In the non-filtered and filtered large phantom, 25% and 19% fewer tumors, respectively, were detected on average compared with the intermediate phantom (p < 0.01). CONCLUSION: The risk of missing hypovascular liver tumors with CT is substantially increased in large patients. A noise filter improves image quality in obese patients.

Authors
Schindera, ST; Torrente, JC; Ruder, TD; Hoppe, H; Marin, D; Nelson, RC; Szucs-Farkas, Z
MLA Citation
Schindera, ST, Torrente, JC, Ruder, TD, Hoppe, H, Marin, D, Nelson, RC, and Szucs-Farkas, Z. "Decreased detection of hypovascular liver tumors with MDCT in obese patients: a phantom study." AJR Am J Roentgenol 196.6 (June 2011): W772-W776.
PMID
21606267
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
196
Issue
6
Publish Date
2011
Start Page
W772
End Page
W776
DOI
10.2214/AJR.10.5351

MR imaging of the adrenal glands

© Cambridge University Press 2011.An adrenal “incidentaloma” is an adrenal mass, 1 cm or more in diameter, which is incidentally discovered during a radiologic examination performed for indications other than an evaluation for adrenal disease. With the widespread use of abdominal ultrasonography, multi-detector row computed tomography (MDCT), magnetic resonance (MR) imaging, and positron emission tomography (PET) the incidence of adrenal incidentalomas has substantially increased. According to recent studies, the overall frequency of adrenal masses is approximately 4% at abdominal MDCT [1], which compares favorably with the 6% prevalence rate reported in a large autopsy study [2]. Although the majority of adrenal incidentalomas are clinically benign adenomas, other frequently reported diagnoses include metastases, pheochromocytomas, and adrenocortical carcinomas. The differential diagnosis between benign and malignant adrenal masses has become a common dilemma, which is compounded in patients with known or suspected of having an extra-adrenal malignancy, where approximately 50% of incidentally detected adrenal lesions are metastatic disease [3].

Authors
Marin, D; Merkle, EM
MLA Citation
Marin, D, and Merkle, EM. "MR imaging of the adrenal glands." Body MR Imaging at 3 Tesla. January 1, 2011. 111-122.
Source
scopus
Publish Date
2011
Start Page
111
End Page
122
DOI
10.1017/CBO9780511978968.010

Gadoxetate disodium-enhanced hepatic MRI: dose-dependent contrast dynamics of hepatic parenchyma and portal vein.

OBJECTIVE: The purpose of this study was to investigate the relative enhancement characteristics of the hepatic parenchyma and portal vein during gadoxetate disodium-enhanced abdominal MRI and to assess whether contrast between the portal vein and the hepatic parenchyma can be improved with higher doses of gadoxetate disodium. MATERIALS AND METHODS: A total of 102 patients (61 women, 41 men) underwent gadoxetate disodium-enhanced abdominal MRI. They received a weight-independent dose of 10 mL of gadoxetate disodium, corresponding to a dose spectrum of 0.02-0.06 mmol/kg body weight. The patients were assigned to one of three dose groups: recommended dose (0.02-0.03 mmol/kg), intermediate dose (0.03-0.045 mmol/kg), or high dose (0.045-0.06 mmol/kg). The signal-to-noise ratios for the portal vein, liver, and the portal vein-to-liver contrast-to-noise ratio were calculated for three consecutive arterial phases, one portal venous phase, and four delayed imaging phases. RESULTS: The delayed phase images of the liver showed statistically significant dose dependency and greater enhancement in the intermediate- and high-dose groups (p < 0.01). Analogously, the portal vein also exhibited greater enhancement in the two higher-dose groups, but the difference was not statistically significant (p > 0.05). Regarding portal vein-to-liver contrast, all three groups had a dose-independent fast parallel increase from baseline toward maximum contrast followed by a steady decline in contrast with no statistically significant differences between dose groups (p > 0.05). CONCLUSION: Portal vein-to-liver contrast during gadoxetate disodium-enhanced hepatic MRI cannot be improved within a dose spectrum of 0.025-0.06 mmol/kg body weight.

Authors
Feuerlein, S; Boll, DT; Gupta, RT; Ringe, KI; Marin, D; Merkle, EM
MLA Citation
Feuerlein, S, Boll, DT, Gupta, RT, Ringe, KI, Marin, D, and Merkle, EM. "Gadoxetate disodium-enhanced hepatic MRI: dose-dependent contrast dynamics of hepatic parenchyma and portal vein." AJR Am J Roentgenol 196.1 (January 2011): W18-W24.
PMID
21178026
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
196
Issue
1
Publish Date
2011
Start Page
W18
End Page
W24
DOI
10.2214/AJR.10.4387

Effect of varying contrast material iodine concentration and injection technique on the conspicuity of hepatocellular carcinoma during 64-section MDCT of patients with cirrhosis

Objectives: The aim of this study was to compare the intraindividual effects of contrast material with two different iodine concentrations on the conspicuity of hepatocellular carcinoma (HCC) and vascular and hepatic contrast enhancement during multiphasic, 64-section multidetector row CT (MDCT) in patients with cirrhosis using two contrast medium injection techniques. Methods: Patients were randomly assigned to one of two groups with an equal iodine dose but different contrast material injection techniques: scheme A, fixed injection duration (25 s), and scheme B, fixed injection flow rate (4 ml s -1). For each group, patients were randomised to receive both moderate-concentration contrast medium (MCCM) and high-concentration contrast medium (HCCM) during two CT examinations within 3 months. Enhancement of the aorta, liver and portal vein and the tumour-to-liver contrast-to-noise ratio (CNR) were compared between MCCM and HCCM. Results: 30 patients (mean age 59 years; range 45-80 years; 16 patients in scheme A and 14 in scheme B)with a total of 31 confirmed HCC noduleswere prospectively enrolled. For scheme B, the mean contrast enhancement of the aorta and tumour-to-liver CNR were significantly higher with HCCM than with MCCM during the hepatic arterial phase (+350.5 HU vs +301.1 HU, p50.001, and +7.5 HU vs +5.5 HU, p50.004). For both groups, there was no significant difference between MCCM and HCCMfor all other comparisons. Conclusion: For a constant injection flow rate, HCCM significantly improves the conspicuity of HCC lesions and aortic enhancement during the hepatic arterial phase on 64-section MDCT in patients with cirrhosis. © 2011 The British Institute of Radiology.

Authors
Guerrisi, A; Marin, D; Nelson, RC; Filippis, GD; Martino, MD; Barnhart, H; Masciangelo, R; Guerrisi, I; Passariello, R; Catalano, C
MLA Citation
Guerrisi, A, Marin, D, Nelson, RC, Filippis, GD, Martino, MD, Barnhart, H, Masciangelo, R, Guerrisi, I, Passariello, R, and Catalano, C. "Effect of varying contrast material iodine concentration and injection technique on the conspicuity of hepatocellular carcinoma during 64-section MDCT of patients with cirrhosis." British Journal of Radiology 84.1004 (2011): 698-708.
PMID
21750137
Source
scival
Published In
British Journal of Radiology
Volume
84
Issue
1004
Publish Date
2011
Start Page
698
End Page
708
DOI
10.1259/bjr/21539234

Precision of iodine quantification in hepatic CT: Effects of reconstruction (FBP and MBIR) and imaging parameters

In hepatic CT imaging, the lesion enhancement after the injection of contrast media is of quantitative interest. However, the precision of this quantitative measurement may be dependent on the imaging techniques such as dose and reconstruction algorithm. To determine the impact of different techniques, we scanned an iodinated liver phantom with acquisition protocols of different dose levels, and reconstructed images with different algorithms (FBP and MBIR) and slice thicknesses. The contrast of lesions was quantified from the images, and its precision was calculated for each protocol separately. Results showed that precision was improved by increasing dose, increasing slice thickness, and using MBIR reconstruction. When using MBIR instead of FBP, the same precision can be achieved at 50% less dose. To our knowledge, this is the first investigation of the quantification precision in hepatic CT imaging using iterative reconstructions. © 2011 SPIE.

Authors
Chen, B; Samei, E; Colsher, J; Barnhart, H; Marin, D; Nelson, R
MLA Citation
Chen, B, Samei, E, Colsher, J, Barnhart, H, Marin, D, and Nelson, R. "Precision of iodine quantification in hepatic CT: Effects of reconstruction (FBP and MBIR) and imaging parameters." Progress in Biomedical Optics and Imaging - Proceedings of SPIE 7961 (2011).
Source
scival
Published In
Proceedings of SPIE
Volume
7961
Publish Date
2011
DOI
10.1117/12.878833

Response

Authors
Martino, MD; Marin, D; Catalano, C
MLA Citation
Martino, MD, Marin, D, and Catalano, C. "Response." Radiology 260.2 (2011): 607-608.
Source
scival
Published In
Radiology
Volume
260
Issue
2
Publish Date
2011
Start Page
607
End Page
608
DOI
10.1148/radiol.11110345

Hepatocellular carcinoma in cirrhotic patients at multidetector CT: Hepatic venous phase versus delayed phase for the detection of tumour washout

Objectives: Our aim was to compare retrospectively hepatic venous and delayed phase images for the detection of tumour washout during multiphasic multidetector row CT (MDCT) of the liver in patients with hepatocellular carcinoma (HCC). Methods: 30 cirrhotic patients underwent multiphasic MDCT in the 90 days before liver transplantation. MDCT was performed before contrast medium administration and during hepatic arterial hepatic venous and delayed phases, images were obtained at 12, 55 and 120 s after trigger threshold. Two radiologists qualitatively evaluated images for lesion attenuation. Tumour washout was evaluated subjectively and objectively. Tumour-to-liver contrast (TLC) was measured for all pathologically proven HCCs. Results: 48 HCCs were detected at MDCT. 46 of the 48 tumours (96%) appeared as either hyper- or isoattenuating during the hepatic arterial phase subjective washout was present in 15 HCCs (33%) during the hepatic venous phase and in 35 (76%) during the delayed phase (p<0.001, McNemar's test). Objective washout was present in 30 of the 46 HCCs (65%) during the hepatic venous phase and in 42 of the HCCs (91%) during the delayed phase (p=0.001). The delayed phase yielded significantly higher mean TLC absolute values compared with the hepatic venous phase (-16.1±10.8 HU vs -10.5±10.2 HU; p<0.001). Conclusions: The delayed phase is superior to the hepatic venous phase for detection of tumour washout of pathologically proven HCC in cirrhotic patients. © 2011 The British Institute of Radiology.

Authors
Furlan, A; Marin, D; Vanzulli, A; Patera, GP; Ronzoni, A; Midiri, M; Bazzocchi, M; Lagalla, R; Brancatelli, G
MLA Citation
Furlan, A, Marin, D, Vanzulli, A, Patera, GP, Ronzoni, A, Midiri, M, Bazzocchi, M, Lagalla, R, and Brancatelli, G. "Hepatocellular carcinoma in cirrhotic patients at multidetector CT: Hepatic venous phase versus delayed phase for the detection of tumour washout." British Journal of Radiology 84.1001 (2011): 403-412.
PMID
21081569
Source
scival
Published In
British Journal of Radiology
Volume
84
Issue
1001
Publish Date
2011
Start Page
403
End Page
412
DOI
10.1259/bjr/18329080

A new iodinated liver phantom for the quantitative evaluation of advanced CT acquisition and reconstruction techniques

An iodinated liver phantom is needed for liver CT related studies, such as the quantification of lesion contrast. Prior studies simulated iodinated hepatic lesions with tubes of iodine solution, which involved complications associated with the setup, differences from actual lesion morphology, and susceptibility to iodine sediments. To develop a dedicated liver phantom with anthropomorphic structures and solid lesions, we designed a phantom with iodinated liver inserts and lesions of different sizes and contrasts. The concentration of iodine in liver parenchyma was determined according to the HU measured from clinical images. The concentrations in high and low contrast lesions were selected so as to provide challenging but reasonable detection tasks. The application of the liver phantom was initially validated at different doses and reconstruction settings. © 2011 SPIE.

Authors
Chen, B; Marin, D; Samei, E
MLA Citation
Chen, B, Marin, D, and Samei, E. "A new iodinated liver phantom for the quantitative evaluation of advanced CT acquisition and reconstruction techniques." Progress in Biomedical Optics and Imaging - Proceedings of SPIE 7961 (2011).
Source
scival
Published In
Proceedings of SPIE
Volume
7961
Publish Date
2011
DOI
10.1117/12.878916

64-Section multi-detector row CT in the preoperative diagnosis of peritoneal carcinomatosis: correlation with histopathological findings.

BACKGROUND: To prospectively investigate the diagnostic accuracy of a 64-section multi-detector row computed tomography (CT) for the detection of peritoneal metastases, with the use of surgery and histopathological findings as the reference standard. METHODS: The study cohort comprised 18 patients with peritoneal carcinomatosis who underwent multiphasic CT with a 64-section CT, 0-119 days before cytoreductive surgery. Transverse CT images along with isotropic reformatted coronal and sagittal images were prospectively and independently evaluated by one of the five staff radiologists in an unblinded fashion. RESULTS: The overall sensitivity, specificity, positive, and negative predictive values of CT for the detection of peritoneal metastases were, respectively, 75% (93 of 124 lesions; confidence interval [CI] 68-84), 92% (118 of 128; CI 85-96), 90% (93 of 103; CI 83-95), and 79% (118 of 149; CI 72-86). For lesions 0.5 cm in diameter or larger, CT yielded a mean sensitivity of 89% (77 of 87; CI 75-97), although sensitivity decreased to only 43% (16 of 37; CI 28-56) for lesions <0.5 cm in diameter. CONCLUSIONS: 64-Section CT with the addition of isotropic reformatted coronal and sagittal images is a very effective technique in the detection of peritoneal metastases of 0.5 cm in diameter or larger, although sensitivity decreases remarkably for lesions <0.5 cm in diameter.

Authors
Marin, D; Catalano, C; Baski, M; Di Martino, M; Geiger, D; Di Giorgio, A; Sibio, S; Passariello, R
MLA Citation
Marin, D, Catalano, C, Baski, M, Di Martino, M, Geiger, D, Di Giorgio, A, Sibio, S, and Passariello, R. "64-Section multi-detector row CT in the preoperative diagnosis of peritoneal carcinomatosis: correlation with histopathological findings." Abdom Imaging 35.6 (December 2010): 694-700.
PMID
19455272
Source
pubmed
Published In
Abdominal Imaging
Volume
35
Issue
6
Publish Date
2010
Start Page
694
End Page
700
DOI
10.1007/s00261-008-9464-9

Detection of hepatic metastases from colorectal cancer: prospective evaluation of gray scale US versus SonoVue® low mechanical index real time-enhanced US as compared with multidetector-CT or Gd-BOPTA-MRI.

PURPOSE: To compare ultrasound (US), low-mechanical index contrast enhanced US (CEUS) and multidetector-CT (MDCT) for the detection of hepatic metastases from colorectal cancer. METHODS AND MATERIALS: From January to June 2006, 110 patients (65 males, 45 females; mean age 62 years; range 39-78) with suspected hepatic lesions from colorectal cancer were prospectively evaluated with US, CEUS and MDCT by two independent readers. Intraoperative ultrasonography (IOUS, n = 45) or a follow-up up for at least 6 months by using MDCT or Gd-BOPTA-enhanced MRI was considered the gold standard. McNemar test was employed. RESULTS: Reference standards revealed 430 metastases in 110 patients. On a patient-by-patients analysis, CEUS improved US sensitivity from 67.4-71.6% to 93.4-95.8% (p < 0.05). On a lesion-by-lesion analysis, CEUS improved the sensitivity of US from 60.9-64.9% to 85.3-92.8% (p < 0.001). The specificity increased from 50-60% to 76.7-83.3%. No significant differences in sensitivity or specificity between CEUS and MDCT were found. Contrast-enhanced US was significantly more sensitive than baseline US in the detection of metastases smaller than 1 cm (p < 0.001) with an increase in sensitivity from 29.1-35% to 63.3-76.6% no significant statistical difference was identified when compared with MDCT (sensitivity of 73.3-75.8%). CONCLUSIONS: CEUS is significantly more accurate than US and highly comparable with MDCT in the detection of liver metastases from colorectal cancer. Therefore, in the evaluation of patients with suspected hepatic metastases from colorectal tumour, US examination must be performed after contrast administration.

Authors
Cantisani, V; Ricci, P; Erturk, M; Pagliara, E; Drudi, F; Calliada, F; Mortele, K; D'Ambrosio, U; Marigliano, C; Catalano, C; Marin, D; Di Seri, M; Longo, F; Passariello, R
MLA Citation
Cantisani, V, Ricci, P, Erturk, M, Pagliara, E, Drudi, F, Calliada, F, Mortele, K, D'Ambrosio, U, Marigliano, C, Catalano, C, Marin, D, Di Seri, M, Longo, F, and Passariello, R. "Detection of hepatic metastases from colorectal cancer: prospective evaluation of gray scale US versus SonoVue® low mechanical index real time-enhanced US as compared with multidetector-CT or Gd-BOPTA-MRI." Ultraschall Med 31.5 (October 2010): 500-505.
PMID
20408122
Source
pubmed
Published In
Ultraschall in der Medizin - European Journal of Ultrasound
Volume
31
Issue
5
Publish Date
2010
Start Page
500
End Page
505
DOI
10.1055/s-0028-1109751

Intraindividual comparison of gadoxetate disodium-enhanced MR imaging and 64-section multidetector CT in the Detection of hepatocellular carcinoma in patients with cirrhosis.

PURPOSE: To prospectively compare gadoxetate disodium-enhanced magnetic resonance (MR) imaging with multiphasic 64-section multidetector computed tomography (CT) in the detection of hepatocellular carcinoma (HCC) in patients with cirrhosis. MATERIALS AND METHODS: Institutional review board approval and informed patient consent were obtained for this prospective study. Fifty-eight patients (39 men, 19 women; mean age, 63 years; age range, 35-84 years) underwent gadoxetate disodium-enhanced MR imaging and multiphasic 64-section multidetector CT. The imaging examinations were performed within 30 days of each other. The two sets of images were qualitatively analyzed in random order by three independent readers in a blinded and retrospective fashion. Using strict diagnostic criteria for HCC, readers classified all detected lesions with use of a four-point confidence scale. The reference standard was a combination of pathologic proof, conclusive imaging findings, and substantial tumor growth at follow-up CT or MR imaging (range of follow-up, 90-370 days). The diagnostic accuracy, sensitivity, and positive predictive value were compared between the two image sets. Interreader variability was assessed. The accuracy of each imaging method was determined by using an adjusted modified chi(2) test. RESULTS: Eighty-seven HCCs (mean size +/- standard deviation, 1.8 cm +/- 1.5; range, 0.3-7.0 cm) were confirmed in 42 of the 58 patients. Regardless of lesion size, the average diagnostic accuracy and sensitivity for all readers were significantly greater with gadoxetate disodium-enhanced MR imaging (average diagnostic accuracy: 0.88, 95% confidence interval [CI]: 0.80, 0.97; average sensitivity: 0.85, 95% CI: 0.74, 0.96) than with multidetector CT (average diagnostic accuracy: 0.74, 95% CI: 0.65, 0.82; average sensitivity: 0.69, 95% CI: 0.59, 0.79) (P < .001 for each). No significant difference in positive predictive value was observed between the two image sets for each reader. Interreader agreement was good to excellent. CONCLUSION: Compared with multiphasic 64-section multidetector CT, gadoxetate disodium-enhanced MR imaging yields significantly higher diagnostic accuracy and sensitivity in the detection of HCC in patients with cirrhosis.

Authors
Di Martino, M; Marin, D; Guerrisi, A; Baski, M; Galati, F; Rossi, M; Brozzetti, S; Masciangelo, R; Passariello, R; Catalano, C
MLA Citation
Di Martino, M, Marin, D, Guerrisi, A, Baski, M, Galati, F, Rossi, M, Brozzetti, S, Masciangelo, R, Passariello, R, and Catalano, C. "Intraindividual comparison of gadoxetate disodium-enhanced MR imaging and 64-section multidetector CT in the Detection of hepatocellular carcinoma in patients with cirrhosis." Radiology 256.3 (September 2010): 806-816.
PMID
20720069
Source
pubmed
Published In
Radiology
Volume
256
Issue
3
Publish Date
2010
Start Page
806
End Page
816
DOI
10.1148/radiol.10091334

Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: A feasibility study

Purpose: The aim of this study was to assess the accuracy of translucency rendering (TR) in computed tomographic (CT) colonography without cathartic preparation using primary 3D reading. Materials and methods: From 350 patients with 482 endoscopically verified polyps, 50 pathologically proven polyps and 50 pseudopolyps were retrospectively examined. For faecal tagging, all patients ingested 140 ml of orally administered iodinated contrast agent (diatrizoate meglumine and diatrizoate sodium) at meals 48 h prior to CT colonography examination and two h prior to scanning. CT colonography was performed using a 64-section CT scanner. Colonoscopy with segmental unblinding was performed within 2 weeks after CT. Three independent radiologists retrospectively evaluated TRCT clonographic images using a dedicated software package (V3D-Colon System). To enable size-dependent statistical analysis, lesions were stratified into the following size categories: small (≤5 mm), intermediate (6-9 mm), and large (≥10 mm). Results: Overall average TR sensitivity for polyp characterisation was 96.6%, and overall average specificity for pseudopolyp characterisation was 91.3%. Overall average diagnostic accuracy (area under the curve) of TR for characterising colonic lesions was 0.97. Conclusions: TR is an accurate tool that facilitates interpretation of images obtained with a primary 3D analysis, thus enabling easy differentiation of polyps from pseudopolyps. © 2010 Springer-Verlag Italia.

Authors
Guerrisi, A; Marin, D; Laghi, A; Di Martino, M; Iafrate, F; Iannaccone, R; Catalano, C; Passariello, R
MLA Citation
Guerrisi, A, Marin, D, Laghi, A, Di Martino, M, Iafrate, F, Iannaccone, R, Catalano, C, and Passariello, R. "Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: A feasibility study." Radiologia Medica 115.5 (August 1, 2010): 758-770.
Source
scopus
Published In
La Radiologia Medica
Volume
115
Issue
5
Publish Date
2010
Start Page
758
End Page
770
DOI
10.1007/s11547-010-0538-8

Detection of pancreatic tumors, image quality, and radiation dose during the pancreatic parenchymal phase: effect of a low-tube-voltage, high-tube-current CT technique--preliminary results.

PURPOSE: To intraindividually compare a low-tube-voltage (80 kVp), high-tube-current (675 mA) computed tomographic (CT) technique with a high-tube-voltage (140 kVp) CT protocol for the detection of pancreatic tumors, image quality, and radiation dose during the pancreatic parenchymal phase. MATERIALS AND METHODS: This prospective, single-center, HIPAA-compliant study was approved by the institutional review board, and written informed consent was obtained. Twenty-seven patients (nine men, 18 women; mean age, 64 years) with 23 solitary pancreatic tumors underwent dual-energy CT. Two imaging protocols were used: 140 kVp and 385 mA (protocol A) and 80 kVp and 675 mA (protocol B). For both protocols, the following variables were compared during the pancreatic parenchymal phase: contrast enhancement for the aorta, the pancreas, and the portal vein; pancreas-to-tumor contrast-to-noise ratio (CNR); noise; and effective dose. Two blinded, independent readers qualitatively scored the two data sets for tumor detection and image quality. Random-effect analysis of variance tests were used to compare differences between the two protocols. RESULTS: Compared with protocol A, protocol B yielded significantly higher contrast enhancement for the aorta (508.6 HU vs 221.5 HU, respectively), pancreas (151.2 HU vs 67.0 HU), and portal vein (189.7 HU vs 87.3 HU), along with a greater pancreas-to-tumor CNR (8.1 vs 5.9) (P < .001 for all comparisons). No statistically significant difference in tumor detection was observed between the two protocols. Although standard deviation of image noise increased with protocol B (11.5 HU vs 18.6 HU), this protocol significantly reduced the effective dose (from 18.5 to 5.1 mSv; P < .001). CONCLUSION: A low-tube-voltage, high-tube-current CT technique has the potential to improve the enhancement of the pancreas and peripancreatic vasculature, improve tumor conspicuity, and reduce patient radiation dose during the pancreatic parenchymal phase.

Authors
Marin, D; Nelson, RC; Barnhart, H; Schindera, ST; Ho, LM; Jaffe, TA; Yoshizumi, TT; Youngblood, R; Samei, E
MLA Citation
Marin, D, Nelson, RC, Barnhart, H, Schindera, ST, Ho, LM, Jaffe, TA, Yoshizumi, TT, Youngblood, R, and Samei, E. "Detection of pancreatic tumors, image quality, and radiation dose during the pancreatic parenchymal phase: effect of a low-tube-voltage, high-tube-current CT technique--preliminary results." Radiology 256.2 (August 2010): 450-459.
PMID
20656835
Source
pubmed
Published In
Radiology
Volume
256
Issue
2
Publish Date
2010
Start Page
450
End Page
459
DOI
10.1148/radiol.10091819

Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: a feasibility study.

PURPOSE: The aim of this study was to assess the accuracy of translucency rendering (TR) in computed tomographic (CT) colonography without cathartic preparation using primary 3D reading. MATERIALS AND METHODS: From 350 patients with 482 endoscopically verified polyps, 50 pathologically proven polyps and 50 pseudopolyps were retrospectively examined. For faecal tagging, all patients ingested 140 ml of orally administered iodinated contrast agent (diatrizoate meglumine and diatrizoate sodium) at meals 48 h prior to CT colonography examination and two h prior to scanning. CT colonography was performed using a 64-section CT scanner. Colonoscopy with segmental unblinding was performed within 2 weeks after CT. Three independent radiologists retrospectively evaluated TRCT clonographic images using a dedicated software package (V3D-Colon System). To enable size-dependent statistical analysis, lesions were stratified into the following size categories: small (< or =5 mm), intermediate (6-9 mm), and large (> or =10 mm). RESULTS: Overall average TR sensitivity for polyp characterisation was 96.6%, and overall average specificity for pseudopolyp characterisation was 91.3%. Overall average diagnostic accuracy (area under the curve) of TR for characterising colonic lesions was 0.97. CONCLUSIONS: TR is an accurate tool that facilitates interpretation of images obtained with a primary 3D analysis, thus enabling easy differentiation of polyps from pseudopolyps.

Authors
Guerrisi, A; Marin, D; Laghi, A; Di Martino, M; Iafrate, F; Iannaccone, R; Catalano, C; Passariello, R
MLA Citation
Guerrisi, A, Marin, D, Laghi, A, Di Martino, M, Iafrate, F, Iannaccone, R, Catalano, C, and Passariello, R. "Diagnostic accuracy of translucency rendering to differentiate polyps from pseudopolyps at 3D endoluminal CT colonography: a feasibility study." Radiol Med 115.5 (August 2010): 758-770.
PMID
20174880
Source
pubmed
Published In
La Radiologia Medica
Volume
115
Issue
5
Publish Date
2010
Start Page
758
End Page
770
DOI
10.1007/s11547-010-0538-8

Effect of beam hardening on arterial enhancement in thoracoabdominal CT angiography with increasing patient size: an in vitro and in vivo study.

PURPOSE: To assess the effect of beam hardening on arterial enhancement in thoracoabdominal computed tomographic (CT) angiography in various body sizes in a phantom and in a clinical study. MATERIALS AND METHODS: An abdominal aortic phantom was placed in three cylindrical water containers simulating a small, an intermediate, and a large patient (diameters of 22, 30, and 40 cm, respectively). CT scanning was performed at 80, 100, and 120 kVp, and aortic attenuation was assessed. In a HIPAA-compliant institutional review board-approved study with waiver of informed consent, thoracoabdominal aortic attenuation was assessed in 100 consecutive patients (75 men, 25 women; mean body weight (BW), 79 kg) undergoing thoracoabdominal 64-section CT angiography at 80 kVp. Overall aortic attenuation in patients grouped according to BW (small patients [n = 26], <70 kg; intermediate patients [n = 41], 70-85 kg; large patients [n = 33], >85 kg) was compared. Overall aortic attenuation was correlated with BW, height, body mass index (BMI), body surface area (BSA), and lateral diameter by using linear regression. RESULTS: Comparison of the intermediate- and large-phantom groups relative to the small-phantom group indicated that mean aortic attenuation decreased by 9.7% and 13.4% at 80 kVp, 9.8% and 15.1% at 100 kVp, and 13.8% and 23.8% at 120 kVp, respectively (P < .001). In the clinical study, the overall aortic attenuation decreased by 11.3% and 20.0% in the intermediate- and large-patient groups relative to the small-patient group, respectively (P < .05). Overall aortic attenuation correlated well with BSA (R = -0.454), height (R = -0.421), and BW (R = -0.414), followed by lateral diameter (R = -0.291) and BMI (R = -0.211). CONCLUSION: Beam hardening may substantially contribute to reduced arterial enhancement in larger patients undergoing thoracoabdominal CT angiography. The beam-hardening effect on arterial enhancement is more pronounced at higher tube voltages.

Authors
Schindera, ST; Tock, I; Marin, D; Nelson, RC; Raupach, R; Hagemeister, M; von Allmen, G; Vock, P; Szucs-Farkas, Z
MLA Citation
Schindera, ST, Tock, I, Marin, D, Nelson, RC, Raupach, R, Hagemeister, M, von Allmen, G, Vock, P, and Szucs-Farkas, Z. "Effect of beam hardening on arterial enhancement in thoracoabdominal CT angiography with increasing patient size: an in vitro and in vivo study." Radiology 256.2 (August 2010): 528-535.
PMID
20656839
Source
pubmed
Published In
Radiology
Volume
256
Issue
2
Publish Date
2010
Start Page
528
End Page
535
DOI
10.1148/radiol.10092086

Dual-energy multidetector CT: how does it work, what can it tell us, and when can we use it in abdominopelvic imaging?

Dual-energy CT provides information about how substances behave at different energies, the ability to generate virtual unenhanced datasets, and improved detection of iodine-containing substances on low-energy images. Knowing how a substance behaves at two different energies can provide information about tissue composition beyond that obtainable with single-energy techniques. The term K edge refers to the spike in attenuation that occurs at energy levels just greater than that of the K-shell binding because of the increased photoelectric absorption at these energy levels. K-edge values vary for each element, and they increase as the atomic number increases. The energy dependence of the photoelectric effect and the variability of K edges form the basis of dual-energy techniques, which may be used to detect substances such as iodine, calcium, and uric acid crystals. The closer the energy level used in imaging is to the K edge of a substance such as iodine, the more the substance attenuates. In the abdomen and pelvis, dual-energy CT may be used in the liver to increase conspicuity of hypervascular lesions; in the kidneys, to distinguish hyperattenuating cysts from enhancing renal masses and to characterize renal stone composition; in the adrenal glands, to characterize adrenal nodules; and in the pancreas, to differentiate between normal and abnormal parenchyma.

Authors
Coursey, CA; Nelson, RC; Boll, DT; Paulson, EK; Ho, LM; Neville, AM; Marin, D; Gupta, RT; Schindera, ST
MLA Citation
Coursey, CA, Nelson, RC, Boll, DT, Paulson, EK, Ho, LM, Neville, AM, Marin, D, Gupta, RT, and Schindera, ST. "Dual-energy multidetector CT: how does it work, what can it tell us, and when can we use it in abdominopelvic imaging?." Radiographics 30.4 (July 2010): 1037-1055.
PMID
20631367
Source
pubmed
Published In
Radiographics : a review publication of the Radiological Society of North America, Inc
Volume
30
Issue
4
Publish Date
2010
Start Page
1037
End Page
1055
DOI
10.1148/rg.304095175

Abdominal magnetic resonance imaging at 3 T: oncological applications.

The gain in signal-to-noise ratio at 3 T magnetic resonance (MR) imaging produces many benefits for abdominal imaging applications, including the capability to reduce acquisition times and/or improve spatial resolution for a variety of pulse sequences, the potential for broader application of parallel imaging techniques, and an increased sensitivity to gadolinium-based contrast media. These advances have the potential of improving the accuracy of MR imaging in the detection, staging, treatment planning, and follow-up of patients with abdominal tumors. At the same time, because certain high-field-strength-related drawbacks could not be compensated for, abdominal 3 T MR imaging should be clinically implemented with caution in some patients (eg, patients with massive ascites).

Authors
Marin, D; Husarik, DB; Boll, DT; Merkle, EM
MLA Citation
Marin, D, Husarik, DB, Boll, DT, and Merkle, EM. "Abdominal magnetic resonance imaging at 3 T: oncological applications." Top Magn Reson Imaging 21.3 (June 2010): 149-156. (Review)
PMID
21847034
Source
pubmed
Published In
Topics in Magnetic Resonance Imaging
Volume
21
Issue
3
Publish Date
2010
Start Page
149
End Page
156
DOI
10.1097/RMR.0b013e3181e8fb7a

Dual-energy CT for characterization of adrenal nodules: initial experience.

OBJECTIVE: The purpose of this study was to determine whether use of dual-energy technique can improve the diagnostic performance of CT in the differential diagnosis of adrenal adenomas and metastatic lesions. SUBJECTS AND METHODS: Thirty-one adrenal nodules were prospectively identified in 17 patients who underwent dual-energy CT at 140 and 80 kVp. Attenuation measurements were performed for each nodule at both tube voltages. The mean attenuation change (increase or decrease) between 140 kVp and 80 kVp was determined for each adrenal nodule. RESULTS: Twenty-six adrenal nodules were benign adenomas (attenuation less than +10 HU or stability for at least 1 year). Five adrenal nodules were classified as metastatic (rapid growth in 1 year and history of extraadrenal malignancy). The mean attenuation change between 140 kVp and 80 kVp was 0.4 +/- 7.1 HU for adenomas and 9.2 +/- 4.3 HU for metastatic lesions (p < 0.003). Fifty percent of adenomas had an attenuation decrease at 80 kVp. All metastatic lesions had an attenuation increase at 80 kVp. With a decrease in attenuation at 80 kVp as an indicator of intracellular lipid within an adenoma, dual-energy CT has 50% sensitivity, 100% specificity, 100% positive predictive value, and 28% negative predictive value in the diagnosis of adenoma. CONCLUSION: A decrease in attenuation of an adrenal lesion between 140 kVp and 80 kVp is a highly specific sign of adrenal adenoma. However, because an increase in attenuation at 80 kVp is seen with metastatic lesions and some adenomas, the sensitivity of this test is low. These data suggest that dual-energy CT can be used to help differentiate some lipid-poor adrenal adenomas from metastatic lesions.

Authors
Gupta, RT; Ho, LM; Marin, D; Boll, DT; Barnhart, HX; Nelson, RC
MLA Citation
Gupta, RT, Ho, LM, Marin, D, Boll, DT, Barnhart, HX, and Nelson, RC. "Dual-energy CT for characterization of adrenal nodules: initial experience." AJR Am J Roentgenol 194.6 (June 2010): 1479-1483.
PMID
20489086
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
194
Issue
6
Publish Date
2010
Start Page
1479
End Page
1483
DOI
10.2214/AJR.09.3476

Pilot study assessing differentiation of steatosis hepatis, hepatic iron overload, and combined disease using two-point dixon MRI at 3 T: in vitro and in vivo results of a 2D decomposition technique.

OBJECTIVE: The purpose of our study was to evaluate whether two-point Dixon MRI using a 2D decomposition technique facilitates metabolite differentiation between lipids and iron in standardized in vitro liver phantoms with in vivo patient validation and allows semiquantitative in vitro assessment of metabolites associated with steatosis, iron overload, and combined disease. MATERIALS AND METHODS: The acrylamide-based phantoms were made to reproduce the T1- and T2-weighted MRI appearances of physiologic hepatic parenchyma and hepatic steatosis-iron overload by the admixture of triglycerides and ferumoxides. Combined disease was simulated using joint admixtures of triglycerides and ferumoxides at various concentrations. For phantom validation, 30 patients were included, of whom 10 had steatosis, 10 had iron overload, and 10 had no liver disease. For MRI an in-phase/opposed-phase T1-weighted sequence with TR/TE(opposed-phase)/TE(in-phase) of 4.19/1.25/2.46 was used. Fat/water series were obtained by Dixon-based algorithms. In-phase and opposed-phase and fat/water ratios were calculated. Statistical cluster analysis assessed ratio pairs of physiologic liver, steatosis, iron overload, and combined disease in 2D metabolite discrimination plots. RESULTS: Statistical assessment proved that metabolite decomposition in phantoms simulating steatosis (1.77|0.22; in-phase/opposed-phase|fat/water ratios), iron overload (0.75|0.21), and healthy control subjects (1.09|0.05) formed three clusters with distinct ratio pairs. Patient validation for hepatic steatosis (3.29|0.51), iron overload (0.56|0.41), and normal control subjects (0.99|0.05) confirmed this clustering (p < 0.001). One-dimensional analysis assessing in vitro combined disease only with in-phase/opposed-phase ratios would have failed to characterize metabolites. The 2D analysis plotting in-phase/opposed-phase and fat/water ratios (2.16|0.59) provided accurate semiquantitative metabolite decomposition (p < 0.001). CONCLUSION: MR Dixon imaging facilitates metabolite decomposition of intrahepatic lipids and iron using in vitro phantoms with in vivo patient validation. The proposed decomposition technique identified distinct in-phase/opposed-phase and fat/water ratios for in vitro steatosis, iron overload, and combined disease.

Authors
Boll, DT; Marin, D; Redmon, GM; Zink, SI; Merkle, EM
MLA Citation
Boll, DT, Marin, D, Redmon, GM, Zink, SI, and Merkle, EM. "Pilot study assessing differentiation of steatosis hepatis, hepatic iron overload, and combined disease using two-point dixon MRI at 3 T: in vitro and in vivo results of a 2D decomposition technique." AJR Am J Roentgenol 194.4 (April 2010): 964-971.
PMID
20308498
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
194
Issue
4
Publish Date
2010
Start Page
964
End Page
971
DOI
10.2214/AJR.09.3011

Gadoxetate disodium-enhanced magnetic resonance cholangiography for the noninvasive detection of an active bile duct leak after laparoscopic cholecystectomy.

We report a case of an endoscopically confirmed biliary leak of the common hepatic duct after laparoscopic cholecystectomy that was prospectively diagnosed on gadoxetate disodium-enhanced magnetic resonance cholangiography. Whereas dynamic contrast-enhanced magnetic resonance images during the early vascular phases helped to rule out the causes of possible complications such as seroma, hematoma, or abdominal abscess, delayed hepatobiliary phase imaging was crucial for unequivocal diagnosis and location of the biliary leak. The diagnosis prompted therapeutic endoscopic retrograde cholangiography whereby a polytetrafluoroethylene-covered nitinol stent graft was successfully placed to repair the biliary injury.

Authors
Marin, D; Bova, V; Agnello, F; Youngblood, R; Midiri, M; Brancatelli, G
MLA Citation
Marin, D, Bova, V, Agnello, F, Youngblood, R, Midiri, M, and Brancatelli, G. "Gadoxetate disodium-enhanced magnetic resonance cholangiography for the noninvasive detection of an active bile duct leak after laparoscopic cholecystectomy." J Comput Assist Tomogr 34.2 (March 2010): 213-216.
PMID
20351507
Source
pubmed
Published In
Journal of Computer Assisted Tomography
Volume
34
Issue
2
Publish Date
2010
Start Page
213
End Page
216
DOI
10.1097/RCT.0b013e3181c1a72c

Percutaneous abscess drainage in patients with perforated acute appendicitis: effectiveness, safety, and prediction of outcome.

OBJECTIVE: The purposes of this study were to retrospectively investigate the effectiveness and safety of CT-guided percutaneous drainage in the treatment of patients with acute appendicitis complicated by perforation and to identify CT findings and procedure-related factors predictive of clinical and procedure outcome. MATERIALS AND METHODS: From March 2005 through December 2008, 41 consecutively registered patients (24 men, 17 women; age range, 18-75 years) underwent CT-guided percutaneous drainage for the management of acute appendicitis complicated by perforation and abscess. Three board-certified radiologists independently reviewed preprocedure CT images. Patients were assigned to one of three risk categories on the basis of the CT findings. Success and failure of percutaneous drainage were defined on a per-patient (i.e., clinical outcome) and per-procedure (i.e., technical outcome) basis. Immediate, periprocedure, and delayed complications were recorded. The association between candidate predictive variables, including demographic characteristics, preprocedure CT findings, and procedure-related factors and clinical or technical outcome was assessed with logistic regression models. RESULTS: Fifty-two CT-guided procedures were performed on 41 patients. Percutaneous drainage had clinical and technical success rates of 90% (37 of 41 patients, 47 of 52 procedures) with no procedure-related complications. In seven patients (19%) clinical success required repeated drainage procedures. A large, poorly defined periappendiceal abscess and an extraluminal appendicolith on preprocedure CT images were independent predictors of clinical failure of percutaneous drainage. CONCLUSION: CT-guided percutaneous drainage is both effective and safe in the treatment of patients with acute appendicitis complicated by perforation and abscess. The clinical and technical success rates are high.

Authors
Marin, D; Ho, LM; Barnhart, H; Neville, AM; White, RR; Paulson, EK
MLA Citation
Marin, D, Ho, LM, Barnhart, H, Neville, AM, White, RR, and Paulson, EK. "Percutaneous abscess drainage in patients with perforated acute appendicitis: effectiveness, safety, and prediction of outcome." AJR Am J Roentgenol 194.2 (February 2010): 422-429.
PMID
20093605
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
194
Issue
2
Publish Date
2010
Start Page
422
End Page
429
DOI
10.2214/AJR.09.3098

Low-tube-voltage, high-tube-current multidetector abdominal CT: improved image quality and decreased radiation dose with adaptive statistical iterative reconstruction algorithm--initial clinical experience.

PURPOSE: To investigate whether an adaptive statistical iterative reconstruction (ASIR) algorithm improves the image quality at low-tube-voltage (80-kVp), high-tube-current (675-mA) multidetector abdominal computed tomography (CT) during the late hepatic arterial phase. MATERIALS AND METHODS: This prospective, single-center HIPAA-compliant study was institutional review board approved. Informed patient consent was obtained. Ten patients (six men, four women; mean age, 63 years; age range, 51-77 years) known or suspected to have hypervascular liver tumors underwent dual-energy 64-section multidetector CT. High- and low-tube-voltage CT images were acquired sequentially during the late hepatic arterial phase of contrast enhancement. Standard convolution FBP was used to reconstruct 140-kVp (protocol A) and 80-kVp (protocol B) image sets, and ASIR (protocol C) was used to reconstruct 80-kVp image sets. The mean image noise; contrast-to-noise ratio (CNR) relative to muscle for the aorta, liver, and pancreas; and effective dose with each protocol were assessed. A figure of merit (FOM) was computed to normalize the image noise and CNR for each protocol to effective dose. Repeated-measures analysis of variance with Bonferroni adjustment for multiple comparisons was used to compare differences in mean CNR, image noise, and corresponding FOM among the three protocols. The noise power spectra generated from a custom phantom with each protocol were also compared. RESULTS: When image noise was normalized to effective dose, protocol C, as compared with protocols A (P = .0002) and B (P = .0001), yielded an approximately twofold reduction in noise. When the CNR was normalized to effective dose, protocol C yielded significantly higher CNRs for the aorta, liver, and pancreas than did protocol A (P = .0001 for all comparisons) and a significantly higher CNR for the liver than did protocol B (P = .003). Mean effective doses were 17.5 mSv +/- 0.6 (standard error) with protocol A and 5.1 mSv +/- 0.3 with protocols B and C. Compared with protocols A and B, protocol C yielded a small but quantifiable noise reduction across the entire spectrum of spatial frequencies. CONCLUSION: Compared with standard FBP reconstruction, an ASIR algorithm improves image quality and has the potential to decrease radiation dose at low-tube-voltage, high-tube-current multidetector abdominal CT during the late hepatic arterial phase.

Authors
Marin, D; Nelson, RC; Schindera, ST; Richard, S; Youngblood, RS; Yoshizumi, TT; Samei, E
MLA Citation
Marin, D, Nelson, RC, Schindera, ST, Richard, S, Youngblood, RS, Yoshizumi, TT, and Samei, E. "Low-tube-voltage, high-tube-current multidetector abdominal CT: improved image quality and decreased radiation dose with adaptive statistical iterative reconstruction algorithm--initial clinical experience." Radiology 254.1 (January 2010): 145-153.
PMID
20032149
Source
pubmed
Published In
Radiology
Volume
254
Issue
1
Publish Date
2010
Start Page
145
End Page
153
DOI
10.1148/radiol.09090094

Characterization of adrenal lesions: comparison of 2D and 3D dual gradient-echo MR imaging at 3 T--preliminary results.

PURPOSE: To retrospectively compare a two-dimensional (2D) and a three-dimensional (3D) technique for in-phase (IP) and opposed-phase (OP) single-breath-hold 3-T magnetic resonance (MR) imaging in the characterization of adrenal lesions, with histopathologic confirmation, computed tomographic findings, or imaging follow-up for a minimum of 6 months used as the reference standard. MATERIALS AND METHODS: This retrospective HIPAA-compliant study was approved by institutional review board, and a waiver of informed consent was obtained. Thirty-four patients (mean age, 57 years) with 37 adrenal lesions underwent 3-T adrenal MR imaging with both 2D and 3D single-breath-hold dual gradient-echo (GRE) MR sequences. Signal intensity (SI) index and adrenal-to-spleen, adrenal-to-liver, and adrenal-to-muscle SI ratios for each lesion were compared between the two techniques by using repeated-measures analysis of variance. The area under the receiver operating characteristic curve (AUC) for each evaluation method was determined, with retrospective selection of suggested thresholds. RESULTS: For the 2D and 3D techniques, the mean SI index and SI ratios were significantly different between adenomas and nonadenomas (P < .05), except for the adrenal-to-liver SI ratio with the 2D technique and the adrenal-to-muscle SI ratio with both techniques. For all evaluation methods, the AUCs were higher, although not statistically significant, for the 3D technique. The two techniques exploited different suggested thresholds for discriminating adenomas from nonadenomas. CONCLUSION: Adrenal adenomas can be readily differentiated from nonadenomas at 3-T MR imaging with either a 2D or 3D single-breath-hold dual GRE MR technique. Depending on the acquisition technique, different suggested thresholds need to be selected for various evaluation methods.

Authors
Marin, D; Soher, BJ; Dale, BM; Boll, DT; Youngblood, RS; Merkle, EM
MLA Citation
Marin, D, Soher, BJ, Dale, BM, Boll, DT, Youngblood, RS, and Merkle, EM. "Characterization of adrenal lesions: comparison of 2D and 3D dual gradient-echo MR imaging at 3 T--preliminary results." Radiology 254.1 (January 2010): 179-187.
PMID
20032151
Source
pubmed
Published In
Radiology
Volume
254
Issue
1
Publish Date
2010
Start Page
179
End Page
187
DOI
10.1148/radiol.09090486

Contrast material administration protocols for 64-MDCT angiography: altering volume and rate and use of a saline chaser to better match the imaging window--physiologic phantom study.

OBJECTIVE: The purpose of our study was to evaluate the effect of varying volumes and rates of contrast material, use of a saline chaser, and cardiac output on aortic enhancement characteristics in MDCT angiography (MDCTA) using a physiologic phantom. MATERIALS AND METHODS: Volumes of 75, 100, and 125 mL of iopamidol, 370 mg I/mL, were administered at rates of 4, 6, and 8 mL/s. The effect of a saline chaser (50 mL of normal saline, 8 mL/s) was evaluated for each volume and rate combination. Normal, reduced (33% and 50%), and increased (25%) cardiac outputs were simulated. Peak aortic enhancement and duration of peak aortic enhancement were recorded. Analysis of variance models were run with these effects, and the estimated mean levels for the sets of factor combinations were determined. RESULTS: Lowering the volume of contrast material resulted in reduced peak enhancement (example, -56.2 HU [p < 0.0001] with 75 vs 125 mL) and reduced duration of 75% peak enhancement (example, -9.0 seconds [p < 0.0001] with 75 vs 125 mL). Increasing the rate resulted in increased peak enhancement (example, 104.5 HU [p < 0.0001] with a rate of 8 vs 4 mL/s) and decreased duration of 75% peak enhancement (example, -13.0 seconds [p < 0.001]). Use of a saline chaser resulted in increased peak enhancement, and this increase was inversely proportional to contrast material volume. Peak enhancement increased when reduced cardiac output was simulated. Peak enhancement decreased when increased cardiac output was simulated. CONCLUSION: Reducing contrast material volume from 125 to 75 mL, increasing the rate to 6 or 8 mL/s, and use of a saline chaser result in an aortic enhancement profile that better matches the approximately 5-second imaging window possible with 64-MDCTA of the abdomen and pelvis. Even smaller volumes of contrast material may be adequate in patients with reduced cardiac output.

Authors
Coursey, CA; Nelson, RC; Weber, PW; Howle, LE; Nichols, EB; Marin, D; DeLong, D
MLA Citation
Coursey, CA, Nelson, RC, Weber, PW, Howle, LE, Nichols, EB, Marin, D, and DeLong, D. "Contrast material administration protocols for 64-MDCT angiography: altering volume and rate and use of a saline chaser to better match the imaging window--physiologic phantom study." AJR Am J Roentgenol 193.6 (December 2009): 1568-1575.
PMID
19933649
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
193
Issue
6
Publish Date
2009
Start Page
1568
End Page
1575
DOI
10.2214/AJR.09.2670

Dual energy versus single energy MDCT: measurement of radiation dose using adult abdominal imaging protocols.

RATIONALE AND OBJECTIVES: The aim of this study was to measure the radiation dose of dual-energy and single-energy multidetector computed tomographic (CT) imaging using adult liver, renal, and aortic imaging protocols. MATERIALS AND METHODS: Dual-energy CT (DECT) imaging was performed on a conventional 64-detector CT scanner using a software upgrade (Volume Dual Energy) at tube voltages of 140 and 80 kVp (with tube currents of 385 and 675 mA, respectively), with a 0.8-second gantry revolution time in axial mode. Parameters for single-energy CT (SECT) imaging were a tube voltage of 140 kVp, a tube current of 385 mA, a 0.5-second gantry revolution time, helical mode, and pitch of 1.375:1. The volume CT dose index (CTDI(vol)) value displayed on the console for each scan was recorded. Organ doses were measured using metal oxide semiconductor field-effect transistor technology. Effective dose was calculated as the sum of 20 organ doses multiplied by a weighting factor found in International Commission on Radiological Protection Publication 60. Radiation dose saving with virtual noncontrast imaging reconstruction was also determined. RESULTS: The CTDI(vol) values were 49.4 mGy for DECT imaging and 16.2 mGy for SECT imaging. Effective dose ranged from 22.5 to 36.4 mSv for DECT imaging and from 9.4 to 13.8 mSv for SECT imaging. Virtual noncontrast imaging reconstruction reduced the total effective dose of multiphase DECT imaging by 19% to 28%. CONCLUSION: Using the current Volume Dual Energy software, radiation doses with DECT imaging were higher than those with SECT imaging. Substantial radiation dose savings are possible with DECT imaging if virtual noncontrast imaging reconstruction replaces precontrast imaging.

Authors
Ho, LM; Yoshizumi, TT; Hurwitz, LM; Nelson, RC; Marin, D; Toncheva, G; Schindera, ST
MLA Citation
Ho, LM, Yoshizumi, TT, Hurwitz, LM, Nelson, RC, Marin, D, Toncheva, G, and Schindera, ST. "Dual energy versus single energy MDCT: measurement of radiation dose using adult abdominal imaging protocols." Acad Radiol 16.11 (November 2009): 1400-1407.
PMID
19596594
Source
pubmed
Published In
Academic Radiology
Volume
16
Issue
11
Publish Date
2009
Start Page
1400
End Page
1407
DOI
10.1016/j.acra.2009.05.002

Focal liver lesions hyperintense on T1-weighted magnetic resonance images.

This article reviews focal liver lesions hyperintense on T1-weighted magnetic resonance (MR) images and describes the underlying etiologies associated with their T1 signal intensity. Although focal liver lesions are commonly detected because of their iso- or hypointensity on T1-weighted images, lesions (benign or malignant) may present with T1 hyperintensity when they contain T1 shortening elements--such as fat, hemorrhage, copper, melanin, and highly concentrated proteins. Our discussion includes the description of state-of-the-art T1-weighted MR sequences and the imaging features of lesions on pre- and postcontrast MR images that are characteristic for lesion composition and useful for making accurate diagnosis.

Authors
Furlan, A; Marin, D; Bae, KT; Lagalla, R; Agnello, F; Bazzocchi, M; Brancatelli, G
MLA Citation
Furlan, A, Marin, D, Bae, KT, Lagalla, R, Agnello, F, Bazzocchi, M, and Brancatelli, G. "Focal liver lesions hyperintense on T1-weighted magnetic resonance images." Semin Ultrasound CT MR 30.5 (October 2009): 436-449. (Review)
PMID
19842568
Source
pubmed
Published In
Seminars in Ultrasound, CT and MRI
Volume
30
Issue
5
Publish Date
2009
Start Page
436
End Page
449

Hypervascular liver tumors: low tube voltage, high tube current multidetector CT during late hepatic arterial phase for detection--initial clinical experience.

PURPOSE: To intraindividually compare a low tube voltage (80 kVp), high tube current computed tomographic (CT) technique with a standard CT protocol (140 kVp) in terms of image quality, radiation dose, and detection of malignant hypervascular liver tumors during the late hepatic arterial phase. MATERIALS AND METHODS: This prospective single-center HIPAA-compliant study had institutional review board approval, and written informed consent was obtained. Forty-eight patients (31 men, 17 women; age range, 35-77 years) with 60 malignant hypervascular liver tumors (mean diameter, 20.1 mm +/- 16.4 [standard deviation]) were enrolled. Pathologic proof of focal lesions was obtained with histopathologic analysis for 33 nodules and imaging follow-up after a minimum of 12 months for 27 nodules. Patients underwent dual-energy 64-section multi-detector row CT. By using vendor-specific software, two imaging protocols-140 kVp and 385 mA (protocol A) and 80 kVp and 675 mA (protocol B)-were compared during the late hepatic arterial phase of contrast enhancement. Paired t tests were used to compare tumor-to-liver contrast-to-noise ratio (CNR) for each lesion, mean image noise, and effective dose between the two data sets. Three readers qualitatively assessed the two data sets in a blinded and independent fashion. Lesion detection and characterization and reader confidence were recorded, as well as readers' subjective evaluations of image quality. Wilcoxon-Mann-Whitney statistical analysis was performed on this assessment. RESULTS: Image noise increased from 5.7 to 11.4 HU as the tube voltage decreased from 140 to 80 kVp (P < .0001), resulting in a significantly lower image quality score (4.0 vs 3.0, respectively) with protocol B according to all readers (P < .001). At the same time, protocol B yielded significantly higher CNR (8.2 vs 6.4) and lesion conspicuity scores (4.6 vs 4.1) than protocol A, along with a lower effective dose (5.1 vs 17.5 mSv) (P < .001 for all). CONCLUSION: By substantially increasing the tumor-to-liver CNR, a low tube voltage, high tube current CT technique improves the conspicuity of malignant hypervascular liver tumors during the late hepatic arterial phase while significantly reducing patient radiation dose.

Authors
Marin, D; Nelson, RC; Samei, E; Paulson, EK; Ho, LM; Boll, DT; DeLong, DM; Yoshizumi, TT; Schindera, ST
MLA Citation
Marin, D, Nelson, RC, Samei, E, Paulson, EK, Ho, LM, Boll, DT, DeLong, DM, Yoshizumi, TT, and Schindera, ST. "Hypervascular liver tumors: low tube voltage, high tube current multidetector CT during late hepatic arterial phase for detection--initial clinical experience." Radiology 251.3 (June 2009): 771-779.
PMID
19346514
Source
pubmed
Published In
Radiology
Volume
251
Issue
3
Publish Date
2009
Start Page
771
End Page
779
DOI
10.1148/radiol.2513081330

Imaging approach for evaluation of focal liver lesions.

Focal liver lesions are common in the general population. Radiology (imaging) plays a pivotal role for the diagnosis, staging, treatment planning, and follow-up of focal liver lesions. To maximize lesion detection and characterization, imaging needs to be performed with appropriate equipment by using protocols carefully designed on the basis of the underlying clinical context. In addition, the decision of an imaging modality cannot be based on the diagnostic accuracy of an imaging test solely but must also consider patient safety and cost-effectiveness.

Authors
Marin, D; Furlan, A; Federle, MP; Midiri, M; Brancatelli, G
MLA Citation
Marin, D, Furlan, A, Federle, MP, Midiri, M, and Brancatelli, G. "Imaging approach for evaluation of focal liver lesions." Clin Gastroenterol Hepatol 7.6 (June 2009): 624-634. (Review)
PMID
19348962
Source
pubmed
Published In
Clinical Gastroenterology and Hepatology
Volume
7
Issue
6
Publish Date
2009
Start Page
624
End Page
634
DOI
10.1016/j.cgh.2009.03.024

Hepatocellular carcinoma in patients with cirrhosis: qualitative comparison of gadobenate dimeglumine-enhanced MR imaging and multiphasic 64-section CT.

PURPOSE: To prospectively investigate whether combined interpretation of dynamic and hepatobiliary phase magnetic resonance (MR) images can improve the accuracy of gadobenate dimeglumine-enhanced MR imaging in the detection of hepatocellular carcinoma (HCC) compared with either dynamic MR or multiphasic multidetector computed tomographic (CT) images alone. MATERIALS AND METHODS: Institutional review board approval and informed patient consent were obtained. Fifty-two patients (39 men, 13 women; mean age, 68 years; range, 38-81 years) suspected of having HCC underwent gadobenate dimeglumine-enhanced MR imaging and multiphasic 64-section multidetector CT. Images were qualitatively analyzed independently by three observers in three separate reading sessions. The alternating free-response receiver operating characteristic (AFROC) method was used to analyze the results. Differences in sensitivity and positive predictive values were calculated at a statistical significance of P < .05. RESULTS: A total of 67 HCCs were detected in 36 patients. The mean area under the AFROC curve (A(z)) was significantly higher for either the combined interpretation of dynamic and hepatobiliary phase MR images (A(z) = 0.95) or dynamic MR images alone (0.91) than for CT images (0.77) (P = .01 for both comparisons). The mean sensitivity of combined interpretation of MR images (0.72) was significantly higher than those of dynamic MR images alone (0.63) and multidetector CT images (0.61) (P = .008 and .001, respectively). The mean positive predictive value was not significantly different among the three imaging sets. CONCLUSION: The combined interpretation of dynamic and hepatobiliary phase MR images improves diagnostic accuracy of gadobenate dimeglumine-enhanced MR imaging for the detection of HCC compared with either dynamic MR or multiphasic multidetector CT images alone.

Authors
Marin, D; Di Martino, M; Guerrisi, A; De Filippis, G; Rossi, M; Ginanni Corradini, S; Masciangelo, R; Catalano, C; Passariello, R
MLA Citation
Marin, D, Di Martino, M, Guerrisi, A, De Filippis, G, Rossi, M, Ginanni Corradini, S, Masciangelo, R, Catalano, C, and Passariello, R. "Hepatocellular carcinoma in patients with cirrhosis: qualitative comparison of gadobenate dimeglumine-enhanced MR imaging and multiphasic 64-section CT." Radiology 251.1 (April 2009): 85-95.
PMID
19332848
Source
pubmed
Published In
Radiology
Volume
251
Issue
1
Publish Date
2009
Start Page
85
End Page
95
DOI
10.1148/radiol.2511080400

Detection of hepatocellular carcinoma in patients with cirrhosis: added value of coronal reformations from isotropic voxels with 64-MDCT.

OBJECTIVE: The purpose of our study was to prospectively assess the added value of isotropic coronal reformations of the liver when using 64-MDCT for the detection of hepatocellular carcinoma (HCC). SUBJECTS AND METHODS: Seventy-one consecutive patients (60 men, 11 women; mean age, 65 years) suspected of having HCC underwent 64-MDCT with coronal reformations. A multiphasic CT protocol that included unenhanced, hepatic arterial, portal venous, and equilibrium phases was performed. Three independent, blinded readers interpreted the transverse scan alone, the coronal scan alone, and the combined transverse and coronal scans for the presence of HCC. Sensitivity, positive predictive value, area under the receiver operating characteristic curve (A(z)), and interpretation time were calculated for each reading session. RESULTS: Seventy-six HCC nodules were confirmed in 48 patients using histopathologic analysis or follow-up with long-term CT, MRI, or both (mean follow-up time, 12 months; range, 12-15 months) as the reference standard. Mean sensitivity, positive predictive value, and A(z) value for HCC detection were, respectively, 84% (191/228 readings), 91% (191/210 readings), and 0.85 for the transverse scan alone; 83% (189/228 readings), 93% (189/203 readings), and 0.86 for the coronal scan alone; and 87% (198/228 readings), 93% (198/213 readings), and 0.87 for combined interpretation of transverse and coronal scans. No comparisons were statistically significant. Forty-eight false-positive interpretations were recorded (19 for the transverse, 14 for the coronal, and 15 for the combined interpretation sets). The reading session in which combined transverse and coronal scans were available for interpretation showed significantly superior reader confidence for HCC detection as well as longer interpretation times (p<0.05 for both comparisons). The average reading time for the combined interpretation of transverse and coronal image sets (mean, 12.1+/-0.8 minutes) was significantly longer than for the transverse image set (7.4+/-1.5 minutes) or the coronal image set (7.1+/-1.3 minutes) (p<0.01). CONCLUSION: With 64-MDCT, the addition of isotropic coronal reformations to transverse images significantly improved reader confidence for the detection of HCC, with no statistically significant improvement in sensitivity, positive predictive value, or diagnostic accuracy (as determined by the A(z) value). This improvement comes at the cost of a longer interpretation time.

Authors
Marin, D; Catalano, C; De Filippis, G; Di Martino, M; Guerrisi, A; Rossi, M; Passariello, R
MLA Citation
Marin, D, Catalano, C, De Filippis, G, Di Martino, M, Guerrisi, A, Rossi, M, and Passariello, R. "Detection of hepatocellular carcinoma in patients with cirrhosis: added value of coronal reformations from isotropic voxels with 64-MDCT." AJR Am J Roentgenol 192.1 (January 2009): 180-187.
PMID
19098199
Source
pubmed
Published In
AJR. American journal of roentgenology
Volume
192
Issue
1
Publish Date
2009
Start Page
180
End Page
187
DOI
10.2214/AJR.07.3652

Gadobenate dimeglumine-enhanced magnetic resonance imaging of primary leiomyoma of the liver.

We report a case of histologically proven primary leiomyoma of the liver that was evaluated with multiphasic 64-section computed tomography (CT) and gadobenate dimeglumine-enhanced magnetic resonance (MR) imaging. This lesion showed vivid enhancement during the arterial phase with sustained enhancement during the hepatic venous and equilibrium phases. During the liver-specific MR imaging phase (150 minutes after contrast injection), the same lesion demonstrated lack of contrast retention, thus appearing hypointense compared with the background liver. Because of this latter finding, the patient underwent partial resection of the liver. In primary hepatic leiomyoma, the absence of contrast uptake during the liver-specific phase of gadobenate dimeglumine-enhanced MR imaging may be inappropriately interpreted as a sign of malignancy, thus leading to unnecessary, aggressive management of such lesions.

Authors
Marin, D; Catalano, C; Rossi, M; Guerrisi, A; Di Martino, M; Berloco, P; Passariello, R
MLA Citation
Marin, D, Catalano, C, Rossi, M, Guerrisi, A, Di Martino, M, Berloco, P, and Passariello, R. "Gadobenate dimeglumine-enhanced magnetic resonance imaging of primary leiomyoma of the liver." J Magn Reson Imaging 28.3 (September 2008): 755-758.
PMID
18777536
Source
pubmed
Published In
Journal of Magnetic Resonance Imaging
Volume
28
Issue
3
Publish Date
2008
Start Page
755
End Page
758
DOI
10.1002/jmri.21519

Focal nodular hyperplasia: typical and atypical MRI findings with emphasis on the use of contrast media.

Focal nodular hyperplasia is a benign hypervascular hepatic tumour, frequently detected in asymptomatic patients undergoing imaging studies for unrelated reasons. Magnetic resonance imaging (MRI) generally allows a confident differential diagnosis with other hypervascular liver lesions, either benign or malignant. In addition, due to the recent development of hepatospecific MRI contrast agents, MRI concomitantly enables functional and morphological information to be obtained, thus providing important clues for the detection and characterization of focal nodular hyperplasia lesions.

Authors
Marin, D; Brancatelli, G; Federle, MP; Lagalla, R; Catalano, C; Passariello, R; Midiri, M; Vilgrain, V
MLA Citation
Marin, D, Brancatelli, G, Federle, MP, Lagalla, R, Catalano, C, Passariello, R, Midiri, M, and Vilgrain, V. "Focal nodular hyperplasia: typical and atypical MRI findings with emphasis on the use of contrast media." Clin Radiol 63.5 (May 2008): 577-585. (Review)
PMID
18374723
Source
pubmed
Published In
Clinical Radiology
Volume
63
Issue
5
Publish Date
2008
Start Page
577
End Page
585
DOI
10.1016/j.crad.2007.06.011

Focal nodular hyperplasia: intraindividual comparison of dynamic gadobenate dimeglumine- and ferucarbotran-enhanced magnetic resonance imaging.

PURPOSE: To intraindividually compare the enhancement pattern of focal nodular hyperplasia (FNH) after dynamic administration of two bolus-injectable liver-specific MR contrast agents, ferucarbotran and gadobenate dimeglumine. MATERIALS AND METHODS: A total of 19 patients with 24 FNHs underwent gadobenate dimeglumine- and ferucarbotran-enhanced MRI during the hepatic arterial-dominant phase (HAP; 25 seconds), the portal-venous phase (PVP; 60 seconds), and the equilibrium phase (EP; 180 seconds). Hepatospecific phases were acquired on T1-weighted images 120 minutes after gadobenate dimeglumine administration, and on T2-weighted images 10 minutes after ferucarbotran administration. Lesion enhancement was independently analyzed by two observers. The kappa statistic was determined to evaluate the agreement between the enhancement patterns of the lesions. RESULTS: On gadobenate dimeglumine-enhanced MR images during HAP, PVP, and EP, FNHs were: hyperintense (24/20/13); isointense (0/4/11); and hypointense (0/0/0). On ferucarbotran-enhanced MR images during HAP, PVP, and EP, FNHs were: hyperintense (2/0/0); isointense (16/9/14); and hypointense (6/15/10). Overall, poor agreement between both contrast agents was observed. During the hepatospecific phases, most (20/24; 83%) FNHs showed a typical enhancement pattern during the delayed hepatospecific phase. CONCLUSION: The dynamic enhancement pattern of FNHs is significantly different between gadobenate dimeglumine- and ferucarbotran-enhanced MRI. With respect to hepatospecific phase, the majority of FNHs showed a typical behavior on both contrast agents.

Authors
Marin, D; Iannaccone, R; Laghi, A; Catalano, C; Murakami, T; Hori, M; Kim, T; Passariello, R
MLA Citation
Marin, D, Iannaccone, R, Laghi, A, Catalano, C, Murakami, T, Hori, M, Kim, T, and Passariello, R. "Focal nodular hyperplasia: intraindividual comparison of dynamic gadobenate dimeglumine- and ferucarbotran-enhanced magnetic resonance imaging." J Magn Reson Imaging 25.4 (April 2007): 775-782.
PMID
17348002
Source
pubmed
Published In
Journal of Magnetic Resonance Imaging
Volume
25
Issue
4
Publish Date
2007
Start Page
775
End Page
782
DOI
10.1002/jmri.20885

Multinodular focal fatty infiltration of the liver: Atypical imaging findings on delayed T1-weighted Gd-BOPTA-enhanced liver-specific MR images

We report a case of pathologically confirmed multinodular focal fatty infiltration. MRI was performed after bolus injection of gadobenate dimeglumine (Gd-BOPTA, Multi-Hance®; Bracco, Milan, Italy), a liver-specific paramagnetic, gadolinium (Gd)-based MR contrast agent that concomitantly enables the acquisition of a standard dynamic phase with timing strategies similar to those used for other extracellular fluid contrast agents, followed by a delayed T1-weighted liver-specific phase (the so-called hepatobiliary phase). In the present case, multiple rounded areas of fatty infiltration, although confidently diagnosed using chemical shift sequences due to a significant signal intensity reduction on out-of-phase images, were unexpectedly hypointense during the delayed liver-specific phase of Gd-BOPTA. Reduced Gd-BOPTA concentration during the liver-specific phase is generally correlated with liver malignancy. Since such lesions can be prospectively mistaken for metastatic disease, we performed a hepatic biopsy to establish a definitive diagnosis. Our empirical observations suggest that Gd-BOPTA uptake may be impaired in fatty infiltrated liver tissue. Because at present there is no report evaluating the kinetics of Gd-BOPTA in fatty liver, further studies are needed to specifically investigate this issue. © 2006 Wiley-Liss, Inc.

Authors
Marin, D; Iannaccone, R; Catalano, C; Passariello, R
MLA Citation
Marin, D, Iannaccone, R, Catalano, C, and Passariello, R. "Multinodular focal fatty infiltration of the liver: Atypical imaging findings on delayed T1-weighted Gd-BOPTA-enhanced liver-specific MR images." Journal of Magnetic Resonance Imaging 24.3 (2006): 690-694.
PMID
16878304
Source
scival
Published In
Journal of Magnetic Resonance Imaging
Volume
24
Issue
3
Publish Date
2006
Start Page
690
End Page
694
DOI
10.1002/jmri.20660

Colorectal polyps: detection with low-dose multi-detector row helical CT colonography versus two sequential colonoscopies.

PURPOSE: To prospectively evaluate the diagnostic accuracy of low-radiation-dose computed tomographic (CT) colonography for detection of colorectal polyps by using two sequential colonoscopies, with the second colonoscopy as the reference standard. MATERIALS AND METHODS: The study was local ethics committee approved, and all patients gave written informed consent. Colonographic images were acquired by using a low-dose multi-detector row CT protocol (effective milliampere-second setting, 10 mAs). Three observers interpreted the CT colonographic data separately and independently by using a two-dimensional technique. Initial conventional colonoscopy was performed by an endoscopist unaware of the CT colonographic findings. Second colonoscopy performed within 2 weeks by a colonoscopist aware of both the CT colonographic and the initial colonoscopic findings served as the reference standard. The sensitivities of CT colonography and initial colonoscopy were calculated on a per-polyp and a per-patient basis. Specificities and positive and negative predictive values also were calculated on a per-patient basis. RESULTS: Eighty-eight patients underwent CT colonography and initial conventional colonoscopy on the same day. Per-polyp sensitivities were 62% and 83% for CT colonography and initial colonoscopy, respectively. Sensitivities for detection of polyps 6 mm in diameter or larger were 86% and 84% for CT colonography and initial colonoscopy, respectively. Initial colonoscopy failed to depict 16 polyps, six of which were correctly detected with CT colonography. For identification of patients with polyps 6 mm in diameter or larger, CT colonography and initial colonoscopy, respectively, had sensitivities of 84% and 90%, specificities of 82% and 100%, positive predictive values of 70% and 100%, and negative predictive values of 91% and 95%. CONCLUSION: Low-dose CT colonography compares favorably with colonoscopy for detection of colorectal polyps 6 mm in diameter or larger, with markedly decreased performance for detection of polyps 5 mm in diameter or smaller.

Authors
Iannaccone, R; Catalano, C; Mangiapane, F; Murakami, T; Lamazza, A; Fiori, E; Schillaci, A; Marin, D; Nofroni, I; Hori, M; Passariello, R
MLA Citation
Iannaccone, R, Catalano, C, Mangiapane, F, Murakami, T, Lamazza, A, Fiori, E, Schillaci, A, Marin, D, Nofroni, I, Hori, M, and Passariello, R. "Colorectal polyps: detection with low-dose multi-detector row helical CT colonography versus two sequential colonoscopies." Radiology 237.3 (December 2005): 927-937.
PMID
16304113
Source
pubmed
Published In
Radiology
Volume
237
Issue
3
Publish Date
2005
Start Page
927
End Page
937
DOI
10.1148/radiol.2373041747

Fibropolycystic liver disease: CT and MR imaging findings.

Fibropolycystic liver disease encompasses a spectrum of related lesions of the liver and biliary tract that are caused by abnormal embryologic development of the ductal plates. These lesions (congenital hepatic fibrosis, biliary hamartomas, autosomal dominant polycystic disease, Caroli disease, choledochal cysts) can be clinically silent or can cause signs and symptoms such as cholangitis, portal hypertension, gastrointestinal bleeding, infections, and space-occupying masses. The different types of fibropolycystic liver disease demonstrate characteristic findings at computed tomography (CT) and magnetic resonance (MR) imaging. Patients with congenital hepatic fibrosis typically have imaging evidence of liver morphologic abnormalities, varices, splenomegaly, renal lesions, and other associated ductal plate abnormalities. Biliary hamartomas usually manifest as multiple cysts that are nearly uniform in size and measure up to 15 mm in diameter. Autosomal dominant polycystic disease typically manifests as an enlarged and diffusely cystic liver. In Caroli disease, cystic or fusiform dilatation of the intrahepatic ducts is seen, as well as the "central dot sign," which corresponds to a portal vein branch protruding into the lumen of a dilated bile duct. Choledochal cyst manifests as a fusiform or cystic dilatation of the extrahepatic bile duct. Awareness of these CT and MR imaging features is essential in detecting and differentiating between various fibropolycystic liver diseases and can assist in proper management.

Authors
Brancatelli, G; Federle, MP; Vilgrain, V; Vullierme, M-P; Marin, D; Lagalla, R
MLA Citation
Brancatelli, G, Federle, MP, Vilgrain, V, Vullierme, M-P, Marin, D, and Lagalla, R. "Fibropolycystic liver disease: CT and MR imaging findings." Radiographics 25.3 (May 2005): 659-670. (Review)
PMID
15888616
Source
pubmed
Published In
Radiographics : a review publication of the Radiological Society of North America, Inc
Volume
25
Issue
3
Publish Date
2005
Start Page
659
End Page
670
DOI
10.1148/rg.253045114

Computed tomography colonography: colon examination or Pandora's box.

Authors
Iannaccone, R; Laghi, A; Catalano, C; Mangiapane, F; Marin, D; Passariello, R
MLA Citation
Iannaccone, R, Laghi, A, Catalano, C, Mangiapane, F, Marin, D, and Passariello, R. "Computed tomography colonography: colon examination or Pandora's box." Gut 53.6 (June 2004): 915-. (Letter)
PMID
15138227
Source
pubmed
Published In
Gut
Volume
53
Issue
6
Publish Date
2004
Start Page
915
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