Endosonography was performed in 76 patients who had endoscopically detected gastroesophageal varices or questionable submucosal lesions, or who were being evaluated for pancreatic carcinoma or pancreatitis. The result were compared with surgery or autopsy results. The patients were divided retrospectively into four groups. Group 1 consisted of 6 patients who underwent surgery or autopsy. Five esophageal varices and 1 fundic varix were diagnosed with endosonography and confirmed histologically. Group 2 consisted of 29 patients undergoing sclerotherapy. Intramural thickening of the esophagus and extramural collaterals were found in 20 of 22 patients, respectively. Endoscopy revealed fibrosis in 10 patients. Group 3 consisted of 16 patients evaluated for pancreatic disease. Fifteen fundic varices, 6 cardiac varices, and 5 extramural collateral veins were found by EUS. Group 4 consisted of 16 patients with questionable submucosal lesions and 9 patients with lesions recognized endoscopically as varices. EUS found varices in all 25 patients. In conclusion, EUS is an important procedure in the diagnosis and follow-up of gastroesophageal varices, and in the identification of questionable abnormalities found endoscopically. The effect of sclerotherapy can be demonstrated as mural thickening with disappearance of submucosal varices.