Gray scale ultrasound diagnosis of obstructive biliary disease.

B-mode ultrasound examinations have been useful in demonstrating cholelithiasis and obstructive dilatation of the gallbladder. It is now possible with gray scale ultrasound technique to demonstrate dilatation of the common bile duct, as differentiated from the gallbladder, and also to show fluid containing spaces within the liver. Discrimination between solid and fluid filled intrahepatic structures is readily made, and dilated biliary radicles are frequently discernible.