Diagnosis for Benign Stenosis of the Vaterian Bile Duct with Percutaneous Biliary Ultrasonography (Pbus)

Ultrasound imaging of benign stenosis of the Vaterian bile duct was examined with a thin ultrasonic probe for intraductal scanning. Nine cases were diagnosed as benign stenosis of the Vaterian bile duct and they were compared cholangiographically with 12 normal papilla cases. A four layered structure was imaged in normal papilla cases, when the probe was in close contact with the inner luminal wall of the papilla. When there was no close contact, the first low echoic layer from the probe side demonstrated separation into two layers, one with a high echo, termed la, and the other with a low echo, termed lb, so that a total of 5 layers were imaged. This was the case for imaging of 5 of the 9 (55.6%) cases of benign stenosis of the Vaterian bile duct and 3 of the 12 normal cases. Ultrasonic images of benign stenosis of the Vaterian bile duct showed first layer thickening, or la and/or lb thickening. Comparing with the results of cholangiography, la thickening mainly corresponded to types I or II, while visualization of lb thickening coincided with type III.