Transhepatic Embolization of Congenital Intrahepatic Portosystemic Venous Shunts with Associated Aneurysms

Intrahepatic shunts between the portal and systemic venous systems with associated aneurysms are extremely rare. A middle aged woman presented with hepatic encephalopathy and was found to have two intrahepatic portosystemic venous shunts with associated aneurysms. Diagnosis was made by duplex ultrasound and was confirmed with contrast enhanced MRI. Treatment was performed percutaneously with an Amplatzer vascular plug.

Portal vein hypoplasia in dogs

Portal vein hypoplasia (PVH) is a congenital disorder, in which microscopic intrahepatic shunts are present, causing blood to bypass the liver sinusoids. As the clinical presentation and the laboratory findings are similar to those in dogs with an extrahepatic portosystemic shunt (EHPSS), differentiation between both disorders is based on the confirmation of a macroscopic shunt by diagnostic imaging techniques. This review highlights the major aspects of PVH, including the differentiation from EHPSSs, and the challenges to diagnose both disorders in dogs with concurrent PVH and EHPSS.

Three-Dimensional Organization of the Hepatic Microvasculature in Hereditary Hemorrhagic Telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant systemic fibrovascular dysplasia. Although hepatic vascular shunts are often observed in HHT, the responsible pathological mechanism is unknown. This issue was addressed by performing a 3-dimensional reconstruction study of the hepatic microvasculature of an HHT-involved liver in a 79-year-old woman. Clinical observation revealed high-output congestive heart failure and hepatic encephalopathy due to arteriovenous and portovenous shunts, respectively. Angiography revealed tortuous dilation of hepatic arterial branches and intrahepatic arteriovenous shunts. The 3-dimensional analysis of the autopsy liver revealed focal sinusoidal ectasia, arteriovenous shunts through abnormal direct communications between arterioles and ectatic sinusoids, and portovenous shunts due to frequent and large communications between portal veins and ectatic sinusoids. Type 1 HHT was suggested by the lack of endoglin immunoreactivity in the liver. The 3-dimensional reconstruction study of hepatic microvasculature was successful in identifying the pathological changes responsible for the intrahepatic shunts in HHT.