Aneurysmal dilatation of the portal vein: a case diagnosed by real-time ultrasonography.

A case of aneurysmal dilatation of the portal vein is reported. A real-time ultrasound study showed a cystic mass behind the pancreatic head, freely communicating with the lumen of the portal, superior mesenteric, and splenic veins, which was diagnostic of portal vein aneurysm. The diagnosis was confirmed by dynamic computed tomography and celiac and superior mesenteric angiograms.