Comparison of endoscopic sphincterotomy techniques after Billroth II gastrectomy using a novel mechanical simulator

A postsurgical anatomy renders endoscopic sphincterotomy (EST) more challenging. Although different EST techniques for such a situation exist, comparative studies are lacking. The aim of the study was to compare the efficacy of different EST techniques using a novel mechanical simulator.

Ten expert endoscopists performed 6 different EST techniques on a novel mechanical Billroth II (BII) simulator in a random sequence. The EST techniques were (1) standard sphincterotome used with a side-viewing endoscope, (2) BII sphincterotome used with a side-viewing endoscope, (3) needle-knife EST guided by biliary endoprosthesis used with a side-viewing endoscope, (4) standard sphincterotome used with a forward-viewing endoscope, (5) BII sphincterotome used with a forward-viewing endoscope, and (6) needle-knife EST guided by biliary endoprosthesis used with a forward-viewing endoscope. The results of videotaped ESTs were evaluated by a blinded expert and duration for each EST modality was calculated.

Needle-knife EST guided by endoprosthesis was rated superior to EST using a BII sphincterotome (p = 0.017) or a standard sphincterotome (p < 0.001). EST using the BII sphincterotome was significantly faster than EST with the needle knife (p = 0.004) and the standard sphincterotome (p = 0.005). There were no differences between the use of a forward-viewing endoscope and a side-viewing endoscope.

In an ex vivo model for EST in B II gastrectomy needle-knife EST guided by endoprosthesis achieved superior ratings in comparison to the use of a BII sphincterotome, although it was more time-consuming. A standard sphincterotome should not be used for such a procedure.