Pancreatic portal cavernoma in patients with cavernous transformation of the portal vein: MR findings

The purpose of the article was to prospectively evaluate the MR findings of pancreatic portal cavernoma in a consecutive series of patients with cavernous transformation of the portal vein. This study was approved by the review board of our institution, and informed consent was obtained. The clinical and biological data and the MR imaging for 20 patients (11 female, 9 male; median age, 49 years) with cavernous transformation of the portal vein and no evidence of previous pancreatic disease were reviewed. The presence of pancreatic portal cavernoma (defined as intra- and/or peripancreatic portal cavernoma), morphological changes in the pancreas, biliary and ductal pancreatic abnormalities, and extension of the portal venous thrombosis were qualitatively assessed. Fifteen patients (75%) had pancreatic portal cavernoma with collateral formation in the pancreas and/or collaterals around the pancreas seen on dynamic contrast-enhanced MR sequences: three patients had both intra- and peripancreatic portal cavernoma, six had intrapancreatic portal cavernoma alone and six had peripancreatic portal cavernoma only. The presence of intra- or peripancreatic portal cavernoma was significantly associated with extension of the thrombosis to the splenic and superior mesenteric veins (p = 0.05). Morphological changes in the pancreas, heterogeneity on T2-weighted sequences and main ductal pancreatic abnormalities were seen in two, four and two patients, respectively. All these patients had intrapancreatic portal cavernoma. Bile duct dilatation was observed in 13 (65%) patients: among them three had extrahepatic dilatation only and these three patients had associated intrapancreatic portal cavernoma. In patients with cavernous transformation of the portal vein, intra- or peripancreatic portal cavernoma is common. In conclusion, intra- or peripancreatic portal cavernoma was only observed in patients with extension of the thrombosis to the splenic vein and/or the superior mesenteric vein.