超声内镜(endoscopic ultrasound,EUS)用于胆道良、恶性疾病的诊断已有20余年的历史,而随着EUS软、硬件技术的不断开发与应用,其在诊断胆道良、恶性病变中的作用正变得越来越不可或缺。将EUS高频超声探头置于十二指肠、胃内或胆总管内以最近的距离可观察肝外胆管,从而获得清晰的肝外胆管声像特征。采用纵轴超声内镜、环扫型超声内镜均可完成对胆道疾病的探查。纵轴超声内镜尤其适用于探查 Endoscopic ultrasound (EUS) has been used in the diagnosis of benign and malignant biliary tract diseases for more than 20 years. With the continuous development and application of EUS software and hardware technology, its role in the diagnosis of benign and malignant biliary lesions Is becoming more and more indispensable. The EUS high-frequency ultrasound probe placed duodenum, stomach or common bile duct in the recent distance can be observed extrahepatic bile duct, so as to obtain a clear extrahepatic bile duct imaging features. Longitudinal ultrasound endoscopy, ring-scan ultrasound endoscopic biliary tract disease can be completed. Longitudinal ultrasound endoscopy is particularly suitable for exploration