对５５例肝外型恶性阻塞性黄疸于手术前进行了内镜超声检查。乳头癌２２例中，诊断正确率为９５％，病变大小判断正确率为８５％；对胰头癌及胆总管末端癌的确诊率也均高于体外“Ｂ”超检查；对乳头癌浸润十二指肠壁深度的判断与病理诊断的符合率为７０％；癌周肿大淋巴结的发现率为７５％。 Endoscopic ultrasonography was performed on 55 patients with extrahepatic malignant obstructive jaundice before surgery. In 22 cases of papillary carcinoma, the diagnostic accuracy rate was 95%, and the correct judgment rate of lesion size was 85%. The diagnosis rate of pancreatic cancer and common bile duct cancer was also higher than that of in vitro “B” ultrasonography; The coincidence rate of judging the depth of the duodenal wall and the pathological diagnosis was 70%; the discovery rate of lymph node enlargement was 75%.