Pancreatic duct “Icicle sign” on MRI for distinguishing autoimmune pancreatitis from pancreatic ductal adenocarcinoma in the proximal pancreas

To determine reliable MRI features of autoimmune pancreatitis (AIP) in the proximal pancreas that could allow its differentiation from pancreatic ductal adenocarcinoma (PDAC). Twenty-three patients with AIP and 61 patients with PDAC in the proximal pancreas underwent MRI. Two observers analyzed MRI for lesion morphology, hypointensity degree on T1-weighted images, enhancement pattern during dynamic phases, capsule-like rim, presence of cysts and...