Figure 7a. Arterioportal fistula in a 3-month-old infant with biliary atresia. (a) Longitudinal color Doppler US image of the liver demonstrates color aliasing in the portal vein and neighboring liver parenchyma, a finding that reflects the presence of a fistula. (b) Color duplex US image demonstrates pulsatile hepatofugal high-velocity flow in the main portal vein. (c) Axial contrast-enhanced fat-suppressed gradient-echo T1-weighted MR image of the liver depicts a dilated main portal vein with marked enhancement (arrow) similar to that of the aorta (arrowhead) and hepatic artery (not shown). Ascites due to portal hypertension is also seen (*). (d) Selective hepatic arteriogram demonstrates retrograde filling of the portal (solid arrow), splenic (open arrow), and superior mesenteric (arrowhead) veins. Feathered arrow indicates the gastroduodenal artery. (e) Celiac axis angiogram obtained after embolization of the right hepatic artery with a microcoil (arrow) shows complete resolution of the fistula. One week later, the fistula recurred through arterial collateralization, and the patient underwent liver transplantation.