MRI of groove pancreatitis.

Purpose: The purpose of this work is to describe the findings on MRI in patients with groove pancreatitis, a specific form of chronic pancreatitis affecting the groove between the pancreatic head, the duodenum, and the common bile duct. Method: MR images, including MR cholangiopancreatography, of five patients with groove pancreatitis were reviewed. Three patients underwent pancreatoduodenectomy due to severe duodenal stenosis, and the MR findings were compared to the histologic findings. Results: A sheet-like mass was demonstrated between the pancreatic head and the duodenum in all patients. The masses were hypointense relative to pancreatic parenchyma on T1-weighted images and iso- to slightly hyperintense on T2-weighted images. After administration of Gd-DTPA, the masses showed delayed enhancement. Histologically. fibrous scar tissue was detected in the groove. Conclusion: MR images can clearly demonstrate the fibrous tissue in the groove in groove pancreatitis, and MR cholangiopancreatography can also provide useful information.