摘要BACKGROUND:?Ampullary carcinoma is a neoplasia with a good prognosis compared to pancreatic cancer. But it is dififcult to early diagnose because it lacks clear clinical symptoms. This study aimed to evaluate the efifcacy of abdominal ultrasonography (US), enhanced computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) in detecting ampullary carcinoma. <br> METHODS:?Forty-one patients with ampullary carcinoma who had been conifrmed pathologically among the inpatients at the First Afifliated Hospital of Zhejiang University School of Medicine from February 2003 to March 2007 were analyzed retrospectively. The accuracy of US, CT, MRCP and ERCP were compared in the diagnosis of ampullary carcinoma. <br> RESULTS:?The accurate rate for detection of ampullary carcinoma with US was 26.83%. The accuracy of CT and ERCP in detection of ampullary tumors was 84.62%and 100%, respectively, which were signiifcantly higher than that of US (P<0.05). The accuracy of MRCP in detection of ampullary tumors was similar to that of US in spite of visualization of obstruction and dilatation of the pancreaticobiliary duct with MRCP. <br> CONCLUSIONS:?Because of the obscure and late onset of symptoms, ampullary carcinoma is dififcult to diagnose early. Multiple imaging techniques should be carried out appropriately in order to early diagnose the disease and improve the prognosis.