Objective: Our purpose is to describe the MRI findings with pathologic correlation, in five patients with groove pancreatitis, a specific form of chronic pancreatitis affecting the groove between the pancreatic head, the common bile duct and duodenum.
Materials and methods: Five patients with pathologically proven (four cases) and clinical and MRI findings (follow-up) consistent with the diagnosis of groove pancreatitis (one case) were reviewed. Three patients underwent cephalic pancreatoduodenectomy (Whipple procedure) due to severe duodenal stenosis; MRI findings were correlated with the histological findings.
Results: In all patients a mass was seen affecting the groove between the pancreatic head and the duodenum. Precontrast images demonstrated hypointense tissue relative to pancreatic parenchyma on T1-weighted images and iso to slightly hyperintense tissue on STIR and T2-weighted images. Postcontrast dynamic Gd-DTPA images, showed peripheral mass enhancement on immediate postgadolinium images and progressive and centripetal mass enhancement on delayed images with good delineation of multiple cysts. Histologically, fibro-inflammatory tissue was demonstrated in the groove and the duodenal wall with obliterative concentric scarring of the distal common bile duct.
Conclusions: MRI findings are demonstrative of the pathologic features characteristic of this entity: the fibrous tissue in the pancreaticoduodenal groove, the duodenal wall inflammation and the groove and/or duodenal wall cyst formation.