Mucosa of the Heister valve in cholelithiasis: transmission and scanning electron microscopic study.

Light, transmission, and scanning electron microscopic studies were performed on 24 gallbladders with thin walls, without inflammation, extirpated by cholecystectomy because of gallstones and on five, free from biliary diseases, obtained by autopsies. Examination of gallbladders and epithelium covering the valvula spiralis (Heister) of the ductus cysticus showed the surface structure of the epithelium covering the Heister valve to be mulberry-like and characteristically pleated, similar to the epithelial lining of the gallbladder. In cases of cholelithiasis, several denuded areas were detectable on the valves. The epithelial lining of the gallbladder was intact. As a new observation, we describe the appearance of worm-like processes on the lateral surface of detached epithelial cells, seen during the course of scanning electron microscopic study. These probably correspond to interdigitating cell junctions observed by transmission electron microscopy.