Value and evaluation of  EUS diagnosis of pancreaticobiliary junction lesions         XIE Xiao-yan, XU Zuo-feng. Ultrasound, the First Affiliated Hospital of Sun Yat-sen, Guangzhou 510080，China
Corresponding author：XIE Xiao-yan, E-mail：xxy1992@21cn.com
Abstract The complex anatomy of the pancreatico-biliary system makes postoperative differential diagnosis of malignancy from benign diseases at this region difficult. Thus，early detection and diagnosis of pancreatico-biliary diseases and accurate staging of periampullary carcinoma are essential for therapy planning and for identification of prognosis. The ability to set the high frequency endoscopic ultrasound transducer at the anterior part of endoscopy in stomach and duodenum and direct proximity to the pancreas and the bile duct, enables accurate preoperative staging of periampullary carcinoma and improves the detection rate of lesions, especially when lesion is too small to be characterized and found by conventional ultrasonography, even by CT or MRI.