Purpose: To evaluate whether measurement of apparent diffusion coefficient (ADC) and pure diffusion coefficient (D) can help to characterize solid pancreatic masses.Materials and Methods: Diffusion‐weighted MR imaging was performed in both a patient group (n = 71; pancreatic cancer [n = 47], mass‐forming pancreatitis [n = 13], solid pseudopapillary neoplasm [n = 6], and neuroendocrine tumor [n = 5]) and a normal control group (n = 11) by applying three b‐factors of 0, 500, and 1000 sec/mm². ADC₅₀₀, ADC₁₀₀₀, D (ADC using b = 500 and 1000 sec/mm²), and perfusion fraction (f, 1‐ exp [‐500 sec/mm² × (ADC₅₀₀ – D)]) of normal pancreas, pancreatic cancer, and mass‐forming pancreatitis were compared using the Kruskal–Wallis test. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic performance and optimal cutoff value of these parameters in differentiating pancreatic cancer from mass‐forming pancreatitis.Results: Normal pancreas had significantly higher mean ADC₅₀₀, ADC₁₀₀₀, and f than either pancreatic cancer (P < 0.001, < 0.001, and 0.004, respectively) or mass‐forming pancreatitis (P < 0.001, < 0.001, and 0.002, respectively). ADC₅₀₀, ADC₁₀₀₀, and D of mass‐forming pancreatitis were significantly lower than those of pancreatic cancer (P = 0.002, 0.004, and 0.014, respectively). Sensitivities and specificities in the diagnosis of pancreatic cancer were 72.3% and 76.9% for ADC₅₀₀, 87.2% and 69.2% for ADC₁₀₀₀, 87.2% and 61.5% for D, and 42.6% and 92.3% for f, respectively.Conclusion: Measurement of ADC and D may be helpful in differentiating pancreatic cancers from mass‐forming pancreatitis. J. Magn. Reson. Imaging 2008;28:928–936.

OBJECTIVE. The purpose of this study was to describe the typical CT and chemical shift MRI findings and to evaluate their usefulness in the diagnosis of focal fatty replacement of the pancreas in five patients.CONCLUSION. The presence of a perceptible focal low-attenuation lesion in the pancreas on CT and the reduction in signal intensity of the lesion on the opposed phase of chemical shift MR images are useful for differentiating focal fatty replacement of the pancreas from true pancreatic neoplasm. Therefore, these imaging findings obviate invasive diagnostic procedures and surgery in the care of patients with focal fatty replacement of the pancreas.

A deep learning–based approach showed high diagnostic performance for identifying patients with solid and cystic pancreatic neoplasms at contrast-enhanced CT. Background Deep learning (DL) may facilitate the diagnosis of various pancreatic lesions at imaging. Purpose To develop and validate a DL-based approach for automatic identification of patients wit...

When hepatocellular carcinoma is being diagnosed with use of gadoxetic acid–enhanced MRI, extending washout appearance to the transitional phase or hepatobiliary phase (instead of restricting it to the portal venous phase) allows higher sensitivity without a reduction in specificity. Background Current Liver Imaging Reporting and Data System guidelines define the washout appearance of gadoxetic acid–enhanced MRI only during the portal venous phase. Defining washout only during the portal venous phase may lead to lower sensitivity for diagnosis of hepatocellular carcinoma (HCC). Purpose To compare the diagnostic performances of three gadoxetic acid–enhanced MRI criteria fono. that part was correcr HCC according to the phases during which washout appearance was determined. Materials and Methods In this retrospective study, patients with a hepatic nodule detected at US surveillance for HCC from January to December 2012 underwent gadoxetic acid–enhanced MRI. Three diagnostic MRI criteria for HCC were defined according to the phases during which washout appearance was observed, with the presence of arterial phase hyperenhancement and hypointensity noted (a) only during the portal venous phase, with washout confined to the portal venous phase; (b) during the portal venous phase or transitio...