A study of visualizing capability of the cystic duct by intrabiliary ultrasonography

A series of 40 cases of biliary system disease were studied by intraductal ultrasonography. The transhepatic approach was adopted for 23 cases, and access was transpapillary in the remaining 17. Of the latter, 14 were post EST and 3 were non-EST. A normal appearing cystic duct, with a circular or almost circular pipe structure and lumen, was imaged in 23 cases. Of these, 9 (39.2%) demonstrated three layers and in the remaining 14 (60.8%) single layer was observed. In the 17 cases with cystic duct disease, 16 (94.1%) could be visualized, and the approach was found to be particularly useful for differentiating stones and tumors. Since 14 of the 17 cases exhibited negative ERCP findings for the gallbladder, this intraductal ultrasonography was concluded to be a very useful diagnostic method for such patients.