A novel teaching tool for visualizing the invisible bile duct axis in 3 dimensions during biliary cannulation (Compact Disc method)

Post written by Mamoru Takenaka, MD, PhD, from the Department of Gastroenterology and Hepatology, Kindai University Faculty of Medicine, Osaka-sayama, Japan.


The selective biliary cannulation is difficult to master, especially for cases of papillae with a long oral protrusion (LOP). In such cases, visualization of the invisible bile duct axis in 3 dimensions (3D) is required. However, there is no dedicated teaching tool for this difficult task. Therefore, we developed a novel and simple teaching tool for visualizing the invisible bile duct axis in 3D, called the CD method.

This video shows how to implement the Compact Disc (CD) method for biliary cannulation, as well as its usefulness in providing feedback to trainees. The CD method is based on imagining CDs, arranged perpendicular to the bile duct axis in the oral protrusion, and a line running through the center hole of each imagined CD.

First, the trainee must imagine that a number of CDs are lined up in the oral protrusion 3 dimensionally. CDs were imagined at the horizontal direction of the several transverse folds of a long oral protrusion (LOP). Manipulation of the catheter through the center hole of each imagined CD is similar in movement to that during adjustment of the axis of the invisible bile duct in cases of LOP.

Learning and teaching biliary cannulation is an important universal theme. This CD method is a very simple but novel teaching method for biliary cannulation. We believe that the acquisition of this technique will improve the ability to overcome cases of difficult biliary cannulation.

Manipulation of the catheter for a LOP is difficult to master, and it is also difficult to teach it. We think this method is useful for both trainees and trainers. In this video, you can see the scenes of teaching using this CD method. This method does not depend on words and can be used in any country. I would be very happy if all ERCPists around the world started to ask “How many CDs of this papilla?” when starting biliary cannulation.

Read the full article online.

The information presented in Endoscopedia reflects the opinions of the authors and does not represent the position of the American Society for Gastrointestinal Endoscopy (ASGE). ASGE expressly disclaims any warranties or guarantees, expressed or implied, and is not liable for damages of any kind in connection with the material, information, or procedures set forth.

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