Visual gaze patterns in trainee endoscopists - a novel assessment tool

Colonoscopy proficiency is significantly influenced by skills achieved during training. Although assessment scores exist, they do not evaluate the impact of visual search strategies and their use is time and labour intensive. Eye-tracking has shown significant differences in visual gaze patterns (VGPs) between expert endoscopists with varying polyp detection rates, so may provide a means of automated assessment and guidance for trainees. This study aimed to assess the feasibility of eye-tracking as a novel assessment method for trainee endoscopists.

Eye-tracking glasses were used to record 26 colonoscopies from 12 endoscopy trainees who were assessed with directly observed procedural scores (DOPS), devised by the Joint Advisory Group (JAG) on GI endoscopy, and a visual analogue score of overall competence. A 'total weighted procedure score' (TWPS) was calculated from 1 to 20. Primary outcomes of fixation duration (FixD) and fixation frequency (FixF) were analysed according to areas of interest (AOIs) with the bowel surface and lumen represented by three concentric rings. Correlation was assessed using Pearson's coefficient. Significance was set at p<.050.

Trainees displayed a significant positive correlation between TWPS and FixD (R = 0.943, p<.0001) and FixF (R = 0.936, p<.0001) in the anatomical bowel mucosa peripheries. Conversely, they had significant negative correlations between TWPS and the anatomical bowel lumen (FixD: R= -0.546, p=.004; FixF: R= -0.568, p=.002).

Higher objective performance scores were associated with VGPs focussing on bowel mucosa. This is consistent with prior analysis showing peripheral VGPs correspond with higher polyp detection rates. Analysis of VGPs, therefore, has potential for training and assessment in colonoscopy.