The "bull's-eye" falciform ligament: a sonographic finding of portal hypertension.

The umbilical vein may dilate as a collateral in portal venous hypertension and become visible within the echodense fat of the falciform ligament. The resulting "bull's-eye" appearance was visible in 5/47 (11%) of patients with cirrhosis secondary to alcohol abuse. It was not visualized in any patients with cholelithiasis who had no evidence of cirrhosis. When demonstrated by ultrasound, this finding should suggest portal venous hypertension.