Extra- and intrasplenic artery aneurysms in portal hypertension.

Extra- and intrasplenic arterial aneurysms have occasionally been encountered in cases of portal hypertension both with and without cirrhosis. The exact pathogenesis is speculative; however, it is postulated that hyperkinetic splenic circulation, probably related to hepatic arterial insufficiency or hypoplasia, constitutes the primary pathogenic mechanism. Other factors such as splenomegaly and hormonal influence may be contributory.