Purpose: To compare single-shot echo-planar imaging (SS EPI) diffusion-weighted MRI (DWI) of abdominal organs between 1.5 Tesla (T) and 3.0T in healthy volunteers in terms of image quality, apparent diffusion coefficient (ADC) values, and ADC reproducibility. Materials and Methods:Eight healthy volunteers were prospectively imaged in this HIPAA-compliant IRBapproved study. Each subject underwent two consecutive scans at both 1.5 and 3.0T, which included breathhold and free-breathing DWI using a wide range of b-values (0 to 800 s/mm 2 ). A blinded observer rated subjective image quality (maximum score¼ 8), and a separate observer placed regions of interest within the liver, renal cortices, pancreas, and spleen to measure ADC at each field strength. Paired Wilcoxon tests were used to compare abdominal DWI between 1.5T and 3.0T for specific combinations of organs, b-values, and acquisition techniques.Results: Subjective image quality was significantly lower at 3.0T for all comparisons (P ¼ 0.0078-0.0156). ADC values were similar at 1.5T and 3.0T for all assessed organs, except for lower liver ADC at 3.0T using b0-500-600 and breathhold technique. ADC reproducibility was moderate at both 1.5T and 3.0T, with no significant difference in coefficient of variation of ADC between field strengths. Conclusion:Compared with 1.5T, SS EPI at 3.0T provided generally similar ADC values, however, with worse image quality. Further optimization of abdominal DWI at 3.0T is needed.

We have presented the largest series to date of the MRI features of both renal oncocytoma and chromophobe RCC. These related entities exhibited similar findings, and no MRI features were reliable in distinguishing between them.

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ADC is significantly lower in high-grade ccRCC compared with low-grade ccRCC and increases the accuracy for detecting high-grade ccRCC compared with conventional MRI features alone.

Findings of this study confirm the ability of the MT contrast-prepared sequence to help distinguish substances of varying protein concentration and suggest that MT imaging is unlikely to be of clinical utility in differentiating healthy and cirrhotic livers.