Alimentary Tract| Volume 53, ISSUE 6, P717-721, June 2021

Water-slider method reduced colonic polyp fragmentation compared with conventional suction retrieval: A prospective randomized controlled study

Published:January 18, 2021DOI:



      After resecting colonic polyps, retrieval through the scope channel may lead to polyp fragmentation, making pathologic evaluation challenging. An easy and reliable method for complete polyp retrieval is needed.


      We developed the water-slider method (WSM), in which the resected polyp is surrounded by water from an auxiliary water channel during suctioning. We prospectively randomized patients who underwent endoscopic resection for colonic polyps in our institute into WSM and non-WSM groups, and evaluated the polyp fragmentation rate.


      Analysis of the data regarding small polyps (≤10 mm in size) revealed that the WSM group had a significantly lower polyp fragmentation rate (8.2%) than the non-WSM group (23.8%, p < 0.001). Polyp retrieval time did not differ significantly between groups. The rate of a clear-cut end on neoplastic polyps was significantly higher in the WSM group (63.8%) than in the non-WSM group (50.0%; p = 0.029).


      The WSM achieved a significantly lower polyp fragmentation rate, allowing for more accurate histologic evaluation than the conventional method. The WSM did not influence the polyp retrieval time.


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