Narrow-needle cholangiography.

Recent modification of percutaneous transhepatic cholangiography has resulted in success rates of 100% in opacifying obstructed biliary systems and of 50% in unobstructed systems. The authors use a 23-gauge needle with a 2- or 5-ml syringe for injecting contrast medium at high pressure. Only one puncture of the liver surface is usually required. Complications have not occurred in unobstructed cases, but early operation is still recommended in obstructed cases.