Abstract
A study was made on the structure of gastric ulcer by means of endoscopic ultrasonography (EUS). EUS was performed in water bath on 3 canine autopsied stomachs with 6 acetic-acid-induced ulcers and 30 human resected stomachs with 45 peptic ulcers, and the endoscopic ultrasonograms were compared with histology. EUS made it possible to diagnose the depth of open ulcers and ulcer scars. The exudate and the fibrinoid necrosis were visualized by EUS as a high echoic area localized at the superficial layer of ulcer base. The granulation tissue and the scar tissue were visualized by EUS as a slightly poor echoic area or more poor echoic area localized at the site deeper than the middle layer of the ulcer base. The histological fusion of the mucosal musucular layer and the proper muscular one was visualized by EUS as the fusion of the 2nd and the 4th layers of the gastric wall. The regenerating mucosa overcovering the base of ulcer was visualized by EUS as a superficial high echoic layer which was connected with the 1st layer of the surrounding normal gastric wall. The pattern of the transection of the ulcer crater was also clearly visualized by EUS.
Based on these fundamental investigations, EUS was performed clinically on 12 cases with gastric ulcers. And the clinical endoscopic ultrasonogram also turned out to correspond with histological findings of their resected specimen. In conclusion, this study presents that EUS is able to be put into clinical evaluation of histological findings of gastric ulcers.
