RÉSUMÉ
Objective To investigate the multi spiral computed tomography(MSCT)characteristics of intraductal papillary neo-plasm of the bile duct(IPNB)and to distinguish the benign and malignant ones.Methods The MSCT and clinical data of 23 patients with IPNB confirmed by pathology were analyzed retrospectively.According to the pathology,they were divided into benign and malignant groups,including 12 cases of benign group(7 cases with low to medium grade intraepithelial neoplasia,and other 5 cases with high grade intraepithelial neoplasia)and 11 cases of malignant group with invasive carcinoma.All patients underwent plain and tri-phasic enhanced CT scans of upper abdomen.The enhanced scan included arterial phase,portal phase and delayed phase.The location,size,growth mode,enhancement type,invasion and metastasis,bile duct manifestations and bile duct stones were analyzed.Independent sample t-test was used to count the transverse diameter,longitudinal diameter and aspect ratio of tumor.Chi square test was used to compare the difference in other parameters between benign and malignant groups.Results There were no significant differences between benign and malignant IPNB groups in the location of the disease,the transverse diameter of the tumor,the dilatation of the bile duct and the presence of the stones(P>0.05).However,the significant differences in tumor growth mode,tumor longitudinal diameter and aspect ratio,enhancement type,invasion of bile duct wall and bile duct truncation were found(P<0.05).Conclusion Benign IPNB is common,while the IPNB with diffuse growth,progressive enhancement,invasion of bile duct wall and extrabiliary structures,and distant metastasis may indicate malignance,and the final diagnosis depends on the pathology.