Radiological Case: Abernethy Malformation

Shibani Mehra, DNB, DMRD; Sonam Walia, MD; M.A. Karthikeyan, MD; U.C. Garga, MD


Appl Radiol. 2018;47(12):28-30. 

In This Article

Imaging Findings

A chest frontal view X-ray showed presence of inferior rib notching. Echocardiography demonstrated a juxtaductal coarctation of the aorta surgically corrected by an end-to-end anastomosis. Abdominal sonography revealed a vascular channel formed by the confluence of the splenic and superior mesenteric veins. This vessel coursed away from the gastro-hepatic ligament and opened into the infrahepatic inferior vena cava (IVC). The left and right branches of the portal vein and intrahepatic portal venules were absent. Color Doppler ultrasonography showed hepatofugal flow in this vascular channel.

An abdominal contrast-enhanced CT scan was performed to evaluate this vascular channel. Axial images demonstrated formation of the portal vein by confluence of the splenic and superior mesenteric veins at the neck of pancreas, but instead of coursing into the liver through the porta hepatis, this vein formed an end-to-side anastomosis with the extra hepatic IVC (Figure 1). The portal vein was absent at the porta and the intrahepatic portal vein branches and venules were not seen (Figure 2). Multiplanar reconstructions allowed accurate depiction of this abnormal extra- hepatic mesenteric-caval shunt (Figure 3). CECT also showed moderate ascites with massive splenomegaly and smooth peritoneal enhancement (Figure 4).

Figure 1.

Coronal reformatted CT image of the abdomen in the portal venous phase. The splenic and superior mesenteric veins join to form the portal vein, which takes an abnormal course and forms an end-to-side shunt with the extrahepatic IVC.

Figure 2.

Axial CT image of the upper abdomen shows the portal vein at the porta hepatis with absent intrahepatic portal venules. The tortuous splenic vein joins the SMV behind the neck of the pancreas. An incidental splenenculus is also noted.

Figure 3.

Sagittal reformatted MDCT image demonstrates the extrahepatic portosystemic shunt between the IVC and portal vein, bypassing the liver.

Figure 4.

The coronal reformatted MDCT image shows the congenital extrahepatic shunt between the IVC and portal vein along with features of peritonitis in the form of enhancing peritoneum and ascites.