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Purpose: To assess the value of 2D multibreath-hold susceptibility-weighted imaging (SWI) for visualizing intratumoral hemorrhage of hepatocellular carcinoma (HCC) and correlate with pathological results. Materials and Methods: Fifty-eight patients with 65 HCCs underwent T1-, T2-, T2*-weighted imaging and SWI. The ability to detect intratumoral hemorrhage for each imaging technique was evaluated. A radiologic-pathological correlation was performed. Results: The area under the receiver operator characteristic (ROC) curve (Az value) for SWI (Az = 0.941) was significantly greater than that for T1WI (Az = 0.748) and T2WI (Az = 0.700) (P = 0.000). When compared with T2*, SWI had slightly higher sensitivity and equal specificity, but the Az value was not significantly different (P = 0.768). The total number of hemorrhages detected by SWI was greatest by factors of 13.3, 6.7, and 2.2 compared to T1WI, T2WI, and T2*, respectively. SWI detected more microbleeds (585 in 25 HCCs) than T1WI (13 in 5 HCCs), T2WI (66 in 11 HCCs), and T2* (238 in 21 HCCs). Conclusion: SWI can accurately visualize internal hemorrhages and provide valuable information regarding the internal architecture of HCC. J. Magn. Reson. Imaging 2012;36:900–906. © 2012 Wiley Periodicals, Inc.

Purpose: To evaluate the role of abdominal susceptibility-weighted imaging (SWI) in the detection of siderotic nodules in cirrhotic liver. Materials and Methods: Forty patients with pathologically identified liver cirrhosis and 40 age/sex-matched normal controls underwent T1-, T2-, T2*-weighted imaging and SWI at 3T. Two radiologists prospectively analyzed all magnetic resonance imaging (MRI) studies. Siderotic nodules detected by each imaging technique were counted for comparison. The conspicuity of siderotic nodules was assessed using a scale from 1 to 3 (1, weak; 2, moderate; 3, prominent). Results: The number of siderotic nodules detected by SWI (3863) was significantly greater than that of T1-weighted imaging (262, P < 0.001), T2-weighted imaging (842, P < 0.001), and T2*-weighted imaging (2475, P < 0.001). No suspected siderotic nodules were detected in normal controls by any imaging technique. Conclusion: SWI appears to provide the most sensitive method to detect siderotic nodules in cirrhotic liver. J. Magn. Reson. Imaging 2011;. © 2011 Wiley-Liss, Inc.

Conventional approaches for fat and water discrimination based on chemical-shift fat suppression have reduced ability to characterize fatty infiltration due to poor contrast of microscopic fat. The multiecho Dixon approach to water and fat separation has advantages over chemical-shift fat suppression: 1) water and fat images can be acquired in a single breathhold, avoiding misregistration; 2) fat has positive contrast; 3) the method is compatible with precontrast and late-enhancement imaging, 4) less susceptible to partial-volume effects, and 5) robust in the presence of background field variation; and 6) for the bandwidth implemented, chemical-shift artifact is decreased. The proposed technique was applied successfully in all 28 patients studied. This included 10 studies with indication of coronary artery disease (CAD), of which four cases with chronic myocardial infarction (MI) exhibited fatty infiltration; 13 studies to rule out arrhythmogenic right ventricular cardiomyopathy (ARVC), of which there were three cases with fibrofatty infiltration and two confirmed with ARVC; and five cases of cardiac masses (two lipomas). The precontrast contrast-to-noise ratio (CNR) of intramyocardial fat was greatly improved, by 240% relative to conventional fat suppression. For the parameters implemented, the signal-to-noise ratio (SNR) was decreased by 30% relative to conventional late enhancement. The multiecho Dixon method for fat and water separation provides a sensitive means of detecting intramyocardial fat with positive signal contrast.

Peripheral arterial disease (PAD) is a major cause of diminished functional capacity and quality of life in a large portion of western populations. While 3D contrast-enhanced (CE) MRA is becoming a modality of choice for clinical PAD examinations, the potential for nephrogenic systemic fibrosis (NSF) in patients with renal insufficiency has triggered a renaissance of interest in non-contrast enhanced (NCE) MRA. Various NCE-MRA strategies employing 3D half-Fourier FSE [1] or balanced SSFP (bSSFP) [2] have shown great promise. Recently, flow-sensitizing dephasing-prepared (FSD) bSSFP was proposed for vessel wall imaging [3]. The present work aimed to investigate the feasibility of MRA in lower legs utilizing FSD-bSSFP combined with ECG-triggering and image subtraction.