Hepatopetal collaterals after portal vein thrombosis following liver transplantation.

Two liver transplant patients with hepatopetal collaterals after portal vein thrombosis are described. Angiographically, the appearance is similar to cavernous transformation of the portal vein. The demonstration of hepatopetal collaterals is diagnostic of portal vein occlusion from whatever cause. After portal vein occlusion, collaterals develop from preexisting periportal vessels which undergo compensatory enlargement and reconstitute the intrahepatic portal vessels. In liver transplant patients, the collateral communications must arise de novo, since all potential collateral pathways are severed at the time of transplantation.