A Novel ex vivo Snare Tip Soft Coagulation Model for Deliberate Self-Practice and Assessing Endoscopic Tip-Control...

Background and Aims Tip control is fundamental to advanced endoscopic procedures but lacks objective assessment tools. We aimed to (1) validate an ex vivo snare tip soft coagulation (STSC) model (HAM-2) by assessing its ability to stratify endoscopists by experience (2) evaluate its efficacy in improving tip control following structured training; and (3) identify baseline predictors of training-related improvement. Methods In this prospective pilot validation study (single-centre, single-arm, pre-/post-design), 13 endoscopists (one expert, seven fellows, five trainees) performed STSC along four standardised 3D-printed shapes on a cooked-ham model. Participants underwent pre-training assessment, two unsupervised, structured self-practice sessions (eight shapes), and post-training assessment. Seven blinded raters (three independent raters per video) evaluated video recordings for their subjective impression of tip control and determined objective metrics (number of correct and incorrect hits) using an online tool. Predictors of improvement were analysed using generalised linear mixed models. Results Thirteen endoscopists performed 104 STSC procedures. At baseline, the expert outperformed fellows and trainees in subjective tip control (95.3 vs. 59.7 vs. 56.3, p < 0.001), speed (40.6 vs. 23.6 vs. 19.7 mm/min, p = 0.002), and accuracy (98.1% vs. 92.7% vs. 90.6%, p = 0.003). Considering the overall cohort, subjective tip control improved by 12.3 (95% CI 6.9-17.7, p < 0.001), speed by 5.5 mm/min (3.1-7.9, p < 0.001), and hit frequency by 6.1 hits/min (3.7-8.5, p < 0.001) post-training. Accuracy did not improve significantly (+1.3%, p = 0.085). Lower endoscopist baseline accuracy and speed independently predicted greater improvement in subjective tip control. Conclusions In this single-centre, single-expert pilot, the HAM-2 model stratified endoscopists by experience (exploratory) and, through self-practice on the model, yielded measurable improvements in tip control following repeated practice. HAM-2 offers a low-cost, reproducible platform for structured self-practice and task-specific performance measurement.