Technique of ultrasound examination during laparoscopic cholecystectomy.

Intracorporeal ultrasonography was used as a new method to examine the bile ducts during laparoscopic cholecystectomy. A prototype rigid 7.5-MHz ultrasound probe, 10 mm in diameter and 50 cm in length, was introduced during 25 laparoscopic cholecystectomies. A dual scanning technique was developed for complete examination of the bile duct. This entailed transverse scanning via the subxyphoid trocar and longitudinal scanning via the umbilical trocar. The intrahepatic ducts were also visualized by placing the probe on the liver surface. Color Doppler imaging was useful to quickly distinguish the duct from vascular structures. Laparoscopic ultrasonography clearly delineated the bile ducts in all operations except one. The time required for imaging was significantly shorter for ultrasonography than for cholangiography. Our preliminary experience demonstrates that a complete examination of the bile ducts can be performed with intracorporeal ultrasonography in a relatively short period of time.