Abstract
Bile duct diseases are complex; besides the malignant lesions represented by cancer and benign lesions such as bile duct stone and cholangitis, the bile duct is liable to tumor invasion or influence of inflammation from the adjacency. The diagnostic system should consist of positive utilization of US, following blood test, to detect even slightest dilatation or minute changes of the bile duct, and their close examination.
MRCP wh ich is drawing attention recently is a highly suitable examination method for bile duct diseases, and its wide-spread usage is much anticipated.
As methods for the close examination, endo scopic ultrasonography, intraductal ultrasonography and peroral/percutaneous cholangioscopy are used in addition to the direct imaging of the bile duct by ERCP or percutaneous transhepatic cholangiography.
For the diagnosis of horizontal spread which is characteristic of the bile duct cancer, cholangioscope is used for superficial spread, cholangiography and IDUS for intraductal spread. For the diagnosis of tumor invasion of the right hepatic artery which influences surgical style, IDUS is used. It is important to select and combine the imaging diagnostic methods most suitable for each lesion.
