Improved delineation of the gallbladder wall with ultrasonography: its value in assessment of the depth of carcinoma invasion.

We examined 30 surgically removed gallbladders with ultrasound using a 10 MHz transducer in a water bath. The sonographic structure of gallbladder wall was imaged as 5 layers. The layer 3, a well-defined hyperechoic zone, was confirmed histologically as corresponding to the boundary between subserosa and muscularis. Since the spreading of gallbladder carcinoma beyond the muscle coat is an important prognostic indicator, high resolution images may well be used to advantage in assessing gallbladder wall penetration intraoperatively, enabling the surgeon to choose the proper operative procedure.