The anatomy and pathology of the porta hepatis demonstrated by gray scale ultrasonography.

Gray scale ultrasound has proved to be a simple, rapid, and reliable means for the investigation of cholestatic jaundice. The distended biliary tree has a characteristic but sometimes confusing appearance on ultrasonic tomography. Gray scale ultrasound can diagnose portal hypertension by visualizing an enlarged, tortuous portal vein. This can be differentiated from the typical shape of the dilated common bile duct by the condition of the intrahepatic biliary canaliculi and by examination of the spleen.