Dynamics of endoscopic snares: a new approach towards more practical and objective performance evaluation

Endoscopic resection using polypectomy snares is a standard method for treating gastrointestinal polyps. However, because few systems can objectively evaluate the capabilities of these snares, endoscopists tend to use them according to their personal preference. We developed a novel objective experimental system to evaluate the dynamic performance of these snares and evaluated their feasibility and reproducibility.

Using our system, we measured the sequential changes in hold-down and tightening force, which are essential capacities for all resection techniques using snares. To evaluate the system’s feasibility, the dynamic performances of three representative snares (product A: an oval-shaped standard snare, product B: a hexagonal-shaped standard snare, and product C: a rounded hard snare) were measured repeatedly.

Forces of each snare were measured to objectively show the dynamic changes in hold-down force during snaring. Results for each time point showed good reproducibility. The forces of product C were larger than those of products A and B, reflecting the subjective estimation on the market of the commercially available snares.

We developed a novel system for objectively measuring the dynamic performance of polypectomy snares. This system warrants further experiments.

Publication History

Received: 25 November 2019

Accepted: 02 March 2020

Article published online:
25 May 2020

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