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Purpose: To report the initial experience and diagnostic performance applying a novel flow-dependent non-contrast-enhanced MR angiography (NCE-MRA) method, in patients with suspected peripheral vascular disease, in comparison with established contrast-enhanced MRA (CE-MRA)., Methods: The lower legs of 34 patients were imaged at 1.5 T with both NCE-MRA and CE-MRA. The NCE-MRA method consisted of a cardiac-gated balanced-SSFP sequence with controllable flow-suppression preparation. Flow-suppressed and unsuppressed datasets were subtracted to obtain angiograms. Two experienced radiologists assessed both NCE-MRA and CE-MRA images, first independently and then in consensus to resolve significant disagreements. Signal loss, vessel conspicuity, vascular disease, venous contamination, artifacts, and diagnostic confidence were assessed., Results: Using the CE-MRA as the "gold standard," the per-segment sensitivity and specificity for detection of significant disease were 81.7% and 90.9%, respectively. Mean diagnostic confidence (scale 0-4) was 3.4 for NCE-MRA and 3.9 for CE-MRA. Most vessel segments were well visualized but the popliteal arteries often suffered some technique-related signal loss., Conclusions: The NCE-MRA method was able to visualize most vessel segments with good or excellent confidence, few artifacts, and excellent background suppression, giving moderate agreement with CE-MRA. However, some segments were poorly visualized, probably due to flow profile distortion in these patients., (Copyright © 2012 Wiley Periodicals, Inc.)

Objectives: The current gold standard for diagnosing vesicoureteric reflux in unsedated infants is the X-ray-based Micturating CystoUrethroGram (MCUG). The aim of this study was to assess the diagnostic performance of interactive MRI for voiding cysto-urethrography (iMRVC)., Methods: 25 infants underwent conventional MCUG followed by iMRVC. In iMRVC, patients were examined using a real-time MR technique, which allows interactive control of image contrast and imaging plane location, before, during and after micturition. Images were assessed for presence and grade of VUR. Parental feedback on both procedures was evaluated., Results: iMRVC gave a sensitivity of 100%, specificity of 90.5% (95% CI: 81.6-99.4%), PPV of 66.7% and NPV of 100% in this population. There was 88% concordance (44/50 renal units) according to the presence of VUR between the two methods, with iMRVC up-grading VUR in 6 units (12%). There was very good agreement regarding VUR grade: Kappa=0.66±0.11 (95% CI 0.43-0.88). 60% of parents preferred the MRI, but did not score the two tests differently., Conclusion: Interactive MRI allows dynamic imaging of the whole urinary tract without ionising radiation exposure. iMRVC gives comparable results to the MCUG, and is acceptable to parents., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Objective: The purpose of this article is to establish the range of normal splenic stiffness in healthy volunteers using MR elastography (MRE) and to investigate any correlation with physiologic parameters and driver position., Subjects and Methods: Sixteen volunteers (mean [+/- SD] age, 37 +/- 9 years) with no history of gastrointestinal, hepatobiliary, or cardiovascular disease were recruited. The MRI protocol included T2-weighted axial and gradient-echo MRE sequences using steady-state 60-Hz excitation. Two MRE acquisitions were performed, one with the driver placed on the right side of the abdomen and the other with the driver placed on the left side. Volunteers' body mass index (BMI), arterial mean blood pressure, age, spleen volume, and liver stiffness were also determined. Two radiologists independently measured the spleen stiffness on the MRE inversion images. The correlations between spleen stiffness and BMI, arterial mean blood pressure, age, spleen volume, and liver stiffness were quantified., Results: Sixteen volunteers underwent MRE. With the driver placed on the right side of the abdomen, the mean splenic stiffness was 3,565 +/- 586 Pa (range, 2,353-4,442 Pa); with the driver on the left side of the abdomen, the mean splenic stiffness was significantly (p < 0.004) different (4,255 +/- 625 Pa; range, 3,194-5,581 Pa). No significant correlation was found between spleen stiffness and BMI, arterial mean blood pressure, age, spleen volume, and liver stiffness (all p > 0.05), Conclusion: These preliminary results in a small number of healthy volunteers show that spleen stiffness is not significantly correlated with BMI, arterial mean blood pressure, spleen volume, or liver stiffness. A significant difference was observed using different driver positions.

This prospective study aims to evaluate the feasibility of DWI at 3 Tesla in patients with advanced ovarian cancer and investigate the differences in vascular signal fraction (VSF) and apparent diffusion coefficient (ADC) values between primary ovarian mass and metastatic disease. Twenty patients with suspected advanced ovarian carcinoma were enrolled in the study. High-resolution T2W FRFSE images were used to confirm the position of three marker lesions: primary ovarian mass, omental cake and peritoneal deposit. Multislice DWI was acquired in a single breath-hold using multiple b-values. The three marker lesions were outlined by an experienced radiologist on ADC and VSF maps. Ovarian lesions showed the highest ADC values. The mean ADC value for peritoneal deposits was significantly lower than for both ovarian lesions (p = 0.03) and omental cake (p = 0.03). The VSF for omental cake was significantly higher than for ovarian lesions (p = 0.01) and peritoneal deposits (p = 0.04). There was a significant positive correlation between ADC and VSF for peritoneal deposits (p = 0.04). DWI in advanced ovarian cancer is feasible at 3 T. There are significant differences in baseline ADC and VSF values between ovarian cancer, omental cake and peritoneal deposits that may explain the mixed treatment response that occurs at different disease sites.