Portal venous system aneurysms: report of five cases.

Until recently aneurysms in the portal venous system were considered to be very rare lesions. This opinion has largely been changed by the increasing number of cases reported in recent years. In this paper we report the cases of five patients with portal venous system aneurysms, including one with splenic vein aneurysm. One patient had associated portal hypertension. The reexamination of two patients 2 years later showed no change in the aneurysms. The sonographic features and related literature are reviewed. In the light of this series and the information in the literature, we recommend that portal venous system aneurysms should no longer be considered exceptionally rare entities.