Purpose: To determine the characteristic magnetic resonance imaging (MRI) features of mass‐forming autoimmune pancreatitis (AIP), which allow its differentiation from pancreatic adenocarcinoma (PAC).Materials and Methods: MR images of 37 patients with either pathologically proven, mass‐forming AIPs (n = 9) or PACs (n = 28) were retrospectively reviewed. The pancreatic MR protocol included unenhanced images, contrast‐enhanced dynamic images, diffusion‐weighted imaging (DWI), and MR‐cholangiopancreatography (MRCP). Two reviewers analyzed the MR images regarding the number, location, morphologic features, and enhancement degree and pattern of the lesions as well as secondary changes of the pancreatic parenchyma, the biliary and pancreatic ducts. The size and apparent diffusion coefficient (ADC) values of the lesions were measured.Results: Although sensitivities were low (28.6%–44.4%), specificities of multiplicity, capsule‐like rim enhancement, and skipped stricture of the biliary or pancreatic duct in mass‐forming AIP were high (100%). Sensitivities and specificities of irregular or geographic shape, delayed enhancement, and a low ADC value <1.26 × 10⁻³ mm²/s in mass‐forming AIP were favorable (71.4%–83.3% and 78.5%–89.3%).Conclusion: Although to differentiate mass‐forming AIP from pancreatic cancer is difficult, the combination of MRI findings including contrast‐enhanced dynamic images, MRCP, and DWI can be a help. J. Magn. Reson. Imaging 2012;36:188–197.

Purpose: To determine the reproducibility of MR elastography (MRE) and the reproducibility and repeatability of the stiffness measurement of MRE in the staging of liver fibrosis.Materials and Methods: Ninety‐four patients, who underwent liver MRE, were included in this study. The patients were classified into group 1 (n = 47) and group 2 (n = 47) according to our knowledge of their histologic hepatic fibrosis (HF) stage. To analyze the reproducibility of MRE, the group 1 patients underwent MRE twice. In addition, to evaluate the repeatability and reproducibility of the stiffness measurement of MRE, a single observer measured the stiffness values of the second MREs in group 1 twice, and two observers independently measured the stiffness values of MRE in group 2. A 95% Bland‐Altman limits of agreement and intraclass correlation coefficients (ICCs) were used to evaluate the reproducibility and repeatability of MRE.Results: In group I, there was no significant difference in the mean liver stiffness values of the first and second MRE examinations, i.e., 3.45 ± 0.25 kPa vs. 3.35 ± 0.23 kPa (p = 0.22). The reproducibility of the MRE examination and the reproducibility and repeatability of the stiffness measurement were high, i.e., the ICCs of each parameter were 0.945, 0.827, and 0.963, respectively, and the 95% limits of agreement were 25.3%, 35.35%, and 18.0%, respectively.Conclusion: MRE is a promising tool for evaluating HF and has high reproducibility of the examination as well as reproducibility and repeatability of the stiffness measurements. J. Magn. Reson. Imaging 2014;39:326–331. © 2013 Wiley Periodicals, Inc.

Kang DH, et al. Immune Netw. 2020 May;20(3):e27. https://doi.org/10.4110/in.2020.20.e27