Faculty Bibliography

OBJECTIVE: The purpose of this study was to compare a 3D T2-weighted imaging sequence with a conventional multiplanar 2D turbo spin-echo T2-weighted sequence in terms of tumor detection and staging of prostate cancer, as well as image quality. MATERIALS AND METHODS: Before prostatectomy, 38 men (mean age, 60 years) with prostate cancer underwent MRI of the prostate with multiplanar 2D turbo spin-echo T2-weighted sequences (total acquisition time, approximately 11 minutes 4 seconds) and a 3D T2-weighted sampling perfection with application optimized contrasts sequence with different flip angle evolutions (SPACE) (acquisition time, approximately 3 minutes 52 seconds). Two blinded observers in consensus reviewed 2D turbo spin-echo T2-weighted images and SPACE images for detection of peripheral zone cancer, extracapsular extension, and seminal vesicle invasion. The observers also assessed subjective image quality and measured the signal-to-noise ratio (SNR) of normal peripheral zone and tumor-to-peripheral zone contrast. Prostatectomy was used as the reference standard. The diagnostic accuracy of the two sequences was assessed with generalized estimating equations and McNemar tests. The agreement between sequences was assessed with kappa coefficients. A paired Wilcoxon signed rank test was used to compare the subjective image quality, SNR, and tumor-to-peripheral zone contrast of the two sequences. RESULTS: For tumor detection and diagnosis of extracapsular extension, there was substantial agreement between the two sequences (kappa = 0.79, kappa = 0.76) with no difference in sensitivity, specificity, positive predictive value, negative predictive value, accuracy (p = 0.25-1), or image quality (p = 0.937). Images obtained with the 2D turbo spin-echo sequence had a significantly higher SNR ratio for normal peripheral zone (p = 0.0010), but SPACE images had significantly greater tumor-to-peripheral zone contrast (p < 0.0001). CONCLUSION: In comparison with conventional multiplanar 2D turbo spin-echo MRI of the prostate, 3D T2-weighted SPACE MRI was associated with substantial time saving (nearly 8 minutes), had similar image quality and accuracy in the diagnosis of tumor and extracapsular extension, and had better tumor conspicuity

AIM: To compare the evaluation times and accuracy of unidirectional panoramic three-dimensional (3D) endoluminal interpretation to traditional two-dimensional (2D) and bidirectional 3D endoluminal techniques. MATERIALS AND METHODS: Sixty-nine patients underwent computed tomography colonography (CTC) after bowel cleansing. Forty-five had no polyps and 24 had at least one polyp > or = 6 mm. Patients underwent same-day colonoscopy with segmental unblinding. Three experienced abdominal radiologists evaluated the data using one of three primary interpretation techniques: (1) 2D; (2) bidirectional 3D; (3) panoramic 3D. Mixed model analysis of variance and logistic regression for correlated data were used to compare techniques with respect to time and sensitivity and specificity. RESULTS: Mean evaluation times were 8.6, 14.6, and 12.1 min, for 2D, 3D, and panoramic, respectively. 2D was faster than either 3D technique (p < 0.0001), and the panoramic technique was faster than bidirectional 3D (p = 0.0139). The overall sensitivity of each technique per polyp and per patient was 68.4 and 76.7% for 2D, 78.9 and 93.3% for 3D; and 78.9 and 86.7% for panoramic 3D. CONCLUSION: 2D interpretation was the fastest overall, the panoramic technique was significantly faster than the bidirectional with similar sensitivity and specificity. The sensitivity for a single reader was significantly lower using the 2D technique. Each reader should select the technique with which they are most successful

PURPOSE: To assess the diagnostic accuracy of image subtraction compared with nonsubtracted images obtained with contrast-enhanced T1-weighted imaging (CE T1WI) for the diagnosis of hepatocellular carcinoma (HCC) necrosis after transarterial chemoembolization (TACE), using liver explant as the reference standard. MATERIALS AND METHODS: Thirty-four patients who underwent TACE within 90 days of liver transplantation and CE MRI scans were assessed by two independent observers who determined the percentage of tumor necrosis using nonsubtracted and subtracted postcontrast phases. Histopathologic percentage of necrosis was retrospectively determined by an experienced pathologist. Spearman rank correlation test was used to correlate the percentages of necrosis from MR evaluation and from pathology. Receiver operating characteristics curve analysis was performed to determine the performance of subtracted versus nonsubtracted datasets for the diagnosis of complete tumor necrosis. RESULTS: There were 57 HCCs (mean size, 2.4 cm; range, 1.2-4.2 cm) diagnosed at explant and identified on MRI, including 16 completely necrotic HCCs. Subtraction demonstrated better interobserver agreement than nonsubtraction dataset for the diagnosis of tumor necrosis. There was a strong correlation between image subtraction and histopathologic assessment of necrosis (r = 0.80-0.86, depending on the phase, P < 0.0001). Subtraction demonstrated significantly higher sensitivity and accuracy for the diagnosis of complete tumor necrosis compared with nonsubtracted dataset. CONCLUSION: Image subtraction enables accurate assessment of necrosis of HCC after TACE with the best accuracy observed at the arterial phase

OBJECTIVE: The purpose of this study was to determine whether the conspicuity of malignant tumors of the pancreas at dual-source dual-energy CT is better with 80-kVp acquisition than with 120-kVp acquisition simulated with a weighted average. MATERIALS AND METHODS: Fifteen patients with pancreatic adenocarcinoma underwent contrast-enhanced dual-source dual-energy CT. The abdominal diameter of all patients was 35 cm or less. Data were reconstructed as a weighted average of the 140- and 80-kVp acquisitions, simulating 120 kVp, and as a pure 80-kVp data set. A region-of-interest cursor was placed within the tumor and the adjacent normal parenchyma, and attenuation differences and contrast-to-noise ratios were calculated for pancreatic tumors at 80 kVp and with the weighted-average acquisition. The 80-kVp and weighted-average images were subjectively compared in terms of lesion conspicuity, image quality, and duct visualization. An exact Wilcoxon's matched pairs signed rank test was used to test whether differences in attenuation, contrast-to-noise ratio, and subjective assessment were greater at 80 kVp. RESULTS: The mean difference in attenuation for each pancreatic tumor and adjacent portion of normal pancreas was 83.27+/-29.56 (SD) HU at 80 kVp and 49.40+/-23.00 HU at weighted-average 120 kVp. Adenocarcinoma attenuation differences were significantly greater at 80 kVp than at 120 kVp (p=0.00006). Contrast-to-noise ratio was significantly higher at 80 kVp than at 120 kVp (p=0.00147). Subjective analysis showed lesion conspicuity (p=0.001) and duct visualization (p=0.0156) were significantly better on the 80-kVp images. CONCLUSION: At portal venous phase dual-source dual-energy CT, the conspicuity of malignant tumors of the pancreas is greater at 80 kVp than with weighted-average acquisition

Background: Electrocardiographic (ECG) criteria for left ventricular (LV) hypertrophy have been shown to have modest predictive values when compared to LV hypertrophy measured by cardiac magnetic resonance (CMR). Prior studies have excluded patients with cardiomyopathies and have not evaluated regional wall thickness in addition to overall LV mass and wall thickness. Thus it remains unknown how well ECG criteria will predict both regional wall thickness and overall LV mass/wall thickness compared to CMR in this population. Objective: To determine if common criteria for LV hypertrophy on ECG are predictive of regional wall thickness and overall LV mass as determined by CMR in patients with cardiomyopathy. Methods: A total of 41 consecutive patients (34 male) greater than 40 years old who underwent CMR for evaluation of cardiomyopathy (both ischemic and non-ischemic) were evaluated. Recent ECG's (mean of 8 days from CMR) were blindly evaluated and patients with a QRS > 120 were excluded from analysis. LV mass and regional wall thickness (anterior, septal, inferior, lateral) were measured at end-diastole on CMR. ECG voltage was examined by two commonly used determinants of LV hypertrophy: 1) Sokolow (SV1+RV5 or V6) and 2) Cornell (SV3 +RaVL) criteria. Pearson r correlations were used to examine the relationship between the CMR and ECG parameters. Results: Mean LV mass was 154 +/- 55 grams, and LV mass index was 76 +/- 31 grams/meters². Sokolow ECG voltage showed good to high correlations with overall LV mass and regional wall thickness, with no significant differences between LV regions (Table 1). Cornell ECG voltage correlated less strongly with CMR parameters, and also showed no significant regional differences. Conclusion: Sokolow ECG voltage criteria for LV hypertrophy demonstrates good to high correlations with LV mass and (Table presented) regional LV wall thickness in patients with cardiomyopathy. Cornell criteria performed worse in this population. No significant differences existed between LV regional wall thickness for either criteria

Background: Fatigue is one of the most common and disabling symptoms in multiple sclerosis (MS), while its underlying mechanisms are still not clear. There is some evidence from MR-spectroscopy that neuronal damage measured by the decline of the amino acid N-acetyl-aspartate (NAA) is associated with increased fatigue in MS. However, other groups found that fatigue in MS can be caused by white matter lesions related disruption of cortico-subcortical pathways. The aim of the present study was to determine whether MR-markers of subcortical white matter disruption like T2w and T1w lesion burden or a measure of the diffuse global neuronal damage (NAA) correlate more closely with fatigue. Materials and Methods: Eighty - two MS patients (57 female) of mean age 49.4 (23-69) years, with CIS (1) RRMS (64) and SPMS (17) with an average disease duration of 17.7 (3-50) years and mean EDSS of 2.9 (0-6.5), were enrolled. There normalized whole brain NAA (WBNAA) amount was obtained with non localized proton MR spectroscopy. T2w and T1w lesion load were obtained from respective MR images by a semi-automated procedure. Fatigue was measured with the FSMC scale. In a multiple linear regression model, correlations between FSMC sum score and T2w lesion load, WBNAA and disease duration were analyzed. Additionally, t-tests between fatigued and non-fatigued patients for T2w and T1w lesion load, WBNAA, disease duration and EDSS were performed. Results: A significant positive correlation between fatigue measured by the FSMC sum score and T2w lesion load (p = 0.029), but not with WBNAA (p = 0.68) or disease duration (p = 0.07) was found. The t-test for T2w (p = 0.0095) and T1w (p = 0.0165) lesion load and EDSS (p= 0.0147) revealed significant differences between MS-patients with and without fatigue. No differences were found for WBNAA in the two groups. Discussion: In our cohort conventional MR-markers, namely T1w and T2w lesion load, and the EDSS correlated more closely with MS fatigue, as objective mesures of neuroaxonal loss. In our global approach diffuse neuronal damage as measured by WBNAA was not a contributor to MS fatigue. This may point to the importance of subcortical disconnection of functional networks as a mechanism contributing to fatigue in MS

We compared image quality and diagnostic accuracy of a noncontrast 3-dimensional magnetic resonance angiography (NC-MRA) technique (balanced steady-state free-precession sequence) to contrast-enhanced MRA (CE-MRA) for evaluation of thoracic aortic disease.The CE-MRA provides 3-dimensional high-resolution images of the thoracic aorta that are important in the evaluation of patients with aortic disease. However, recent concerns with the potential nephrotoxic effects of gadolinium contrast medium limit the application of CE-MRA for patients who have significant renal insufficiency.Twenty-one patients (mean age, 51 yr; 18 men) who underwent NC-MRA and CE-MRA for evaluation of thoracic aortic disease were retrospectively identified. Data sets were reviewed by 2 readers who were blinded to the patients' information. The thoracic aorta was divided into 5 segments. Image quality and reader confidence for diagnosis of aortic pathology were rated on 5-point scales. The Wilcoxon matched-pairs signed rank test and the Student t test were used for comparisons.The NC-MRA identified all pathologic findings with 100% diagnostic accuracy and similar reader confidence, when compared with CE-MRA. Although overall image quality was not significantly different, superior image quality was observed at the aortic root (4.4 +/- 0.8 vs 3.2 +/- 0.9, P <0.0005) and ascending aorta (4.1 +/- 1 vs 3.7 +/- 0.9, P=0.05) respectively.In conclusion, NC-MRA is a useful alternative for evaluation and follow-up of thoracic aortic disease, especially for patients with poor intravenous access or contraindications to gadolinium use

Background: The possible role of immune system dysregulation in Tourette's disorder (TD) has been increasingly recognized. Studies implicate cytokine imbalances in TD, including tumor necrosis factor (TNF)-alpha, interleukin (IL)-2, and IL-12. Omega-3 Fatty Acids (omega-3FA) are widely used as an alternative treatment for TD and are known to have anti-inflammatory properties. The present study is the first double-blind, placebo-controlled trial examining the therapeutic efficacy and cytokine-specific effects of omega-3FA and olive oil (placebo) in children and adolescents with TD. We hypothesized that: (1) improvement of tics and obsessive compulsive disorder (OCD) symptoms would be positively associated with cytokine plasma concentrations in both treatment groups; (2) these associations would be more pronounced in the omega-3FA group. Methods: Thirty-three children and adolescents with TD (28 males), ages six to 18, were enrolled in a 20-week, double-blind, placebo-controlled trial; 17 were randomly assigned to omega-3FA and 16 to olive oil treatment. Clinician-rated measures included the (Table presented) Yale Global Tic Severity Scale (YGTSS) and the Children's Yale- Brown Obsessive Compulsive Scale (CY-BOCS). Blood samples were collected at 8-9 am after a 12-hour fast at baseline, midpoint, and endpoint weeks and analyzed using enzyme-linked immunosorbent assays. Generalized estimating equations (GEE) based on a binary logistic regression model was used to assess cytokine predictability of OCD and Tic symptom improvement (i.e., CY-BOCS and YGTSS tic score), accounting for age and gender. Spearman correlations characterized associations between cytokines and severity scores. Results: Table 1 and Table 2 show GEE predictabilities and Spearman correlations. Conclusions: Findings suggest that IL-6 and TNF-alpha may play a role in TD treatment response, possibly affected by omega-3FA

Purpose: To determine the frequency of intraductal papillary mucinous neoplasm (IPMN) in patients with and without invasive ductal adenocarcinoma (IDAC). Methods: 82 patients underwent pancreatectomy for pancreas adenocarcinoma. 68/82 subjects underwent at least one preoperative imaging study including CT (n = 43), MRI (n = 25), or both (n = 12). Imaging studies were retrospectively evaluated to determine if IPMN was present in the gland at a location distant from IDAC. In 183 different adult patients undergoing MRI for renal mass, images were evaluated to determine the frequency of IPMN. Fisher's exact test was used to test whether the prevalence of IPMN was greater among patients with pancreas cancer than those without. Results: Five of 68 (7.3%) patients who underwent pancreatic resection for IDAC had IPMN at a site distant from the cancer. Two of 182 (1.1%) patients undergoing MRI for renal cancer had imaging evidence of IPMN. There was a significant difference (p = 0.017) in the prevalence of IPMN between patients with and without IDAC. The odds ratio for IPMN as a predictor of pancreas cancer was estimated as 7.18. Conclusion: IPMN occurs with increased frequency in patients with pancreas cancer as opposed to those without pancreas cancer. and IAP