Numerical evaluation of the efficacy of small-caliber colonoscopes in reducing patient pain during a colonoscopy.

Patient pain caused by a colonoscope is one of the main complications in completing a colonoscopy. Currently, randomized controlled trial (RCT) is one of the most used methods to evaluate the efficacy of small-caliber (SC) colonoscopes in reducing patient pain during a colonoscopy, compared with a standard colonoscope (SDC). However, many disturbing factors, including endoscopists' skills, characteristics of patients and new technical features of the colonoscope (passive bending and high force transmission shaft), limit the reliability and generalizability of each finding in current RCTs. This paper focuses on modeling the insertion of colonoscopes within colon models using an explicit finite element method (FEM). Such a numerical model could overcome the limitations in RCTs. At the same time, it is expected to evaluate the efficacy of the small-caliber colonoscopes in reducing patient pain during a colonoscopy, while considering the effects of patient characteristics, including age, region and gender. The simulation results in this work showed that: compared with the SDC, a SC colonoscope may be more helpful in reducing discomfort for older patients, patients with smaller colon diameters and females.