Benign lesions of the upper GI tract by means of endoscopic ultrasonography.

In contrast to conventional ultrasound tomography endoscopic ultrasonography (EUS) allows an exact evaluation of the wall of the upper GI tract. The gastric and esophageal walls give a typical five-layer image presumably corresponding to the mucosa (two inner layers), submucosa (middle echogenic layer), muscularis propria (outer echo-poor layer), and serosa (outer echogenic layer). A thickening of the mucosa may be demonstrated in Ménétrier's disease. In patients with gastric antrum ulcers there is considerable thickening of the gastric wall, especially of the submucosa and muscularis. Benign gastric and esophageal submucosal tumors are easily localized between the different layers. They are easily distinguished from malignant processes by means of EUS. In patients with polypoid endoscopic aspect due to an impression from outside, a tumor can be easily excluded.