Gadoxetate disodium-enhanced MR imaging is more reliable for staging hepatic fibrosis than are diffusion-weighted MR imaging, hematologic, and clinical parameters.

The pancreas-to-muscle SI ratio on T1-weighted MR images of the pancreas may be a potential biomarker for assessment of pancreatic fibrosis and prediction of postoperative pancreatic fistula.

When LBW, rather than TBW or BV, is used, the iodine dose required to achieve consistent hepatic enhancement may be estimated more precisely and with reduced patient-to-patient variability.

DKI can be a new option for the assessment of posttherapeutic response in HCC.

Purpose:To determine the optimal b values required for diffusion-weighted (DW) imaging of the liver in the detection and characterization of benign and malignant hepatic lesions. Materials and Methods:MR images obtained in 76 patients including 28 malignant hepatic lesions (21 hepatocellular carcinomas and 7 metastases) and 27 benign lesions (12 hemangiomas and 15 cysts) were reviewed. DWecho planner images (EPIs; b values with100, 200, 400, and 800 s/mm 2 ) were reviewed solely first, and then with T2-weighted EPIs (b ϭ 0 s/mm 2 ).Results: Sensitivity for malignant lesions (74%) was highest on DW-EPIs with b value of 100 s/mm 2 and T2-weighted EPIs combined (P Ͻ 0.05), and sensitivity for benign lesions (87%) was highest on DW-EPIs with b value of 800 s/mm 2 and T2-weighted EPIs (P Ͻ 0.05). Specificities were comparably high for all sequences. The Az values for malignant lesions were 0.94, 0.90, 0.87, and 0.89, and those for benign lesions were 0.91, 0.89, 0.87, and 0.94 on DW-EPIs with b values of 100, 200, 400, and 800 and T2-weighted EPIs combined, respectively. Hepatic cysts were clearly distinguished with the cutoff ADC value of 2.5 ϫ10 Ϫ3 mm 2 /s using a b value of 400 s/mm 2 or greater.Conclusion: DW-EPIs with middle b values were not required in the detection and characterization of benign and malignant hepatic lesions.