# Eye movement patterns associated with colorectal adenoma detection: Post hoc analysis of randomized controlled trial

## TL;DR

This study found that endoscopists who focus more on the lower part of the screen and move their eyes slowly are better at detecting colorectal adenomas.

## Contribution

The study identifies specific eye movement parameters—lower peripheral gaze rate and slower eye movement—as predictors of adenoma detection during colonoscopies.

## Key findings

- A lower peripheral gaze rate (13.7% vs. 9.5%) was associated with adenoma detection (P = 0.004).
- A smaller average eye movement distance (29.9 vs. 33.3 pixels/30 ms) was linked to adenoma detection (P = 0.022).
- Logistic regression confirmed lower peripheral gaze rate and slower eye movement as independent predictors of adenoma detection.

## Abstract

The adenoma detection rate is higher among endoscopists who spend more time observing screen edges during colonoscopies. Nonetheless, eye movement parameters related to lesion detection remain unknown. This study aimed to determine the specific eye movement parameters related to colorectal adenoma detection, including the gaze rate in a particular area and eye movement speed.

This study was a post hoc analysis of a randomized controlled trial investigating the effect of modifying eye movements of endoscopists on colorectal adenoma detection. Gaze rate at a specific area and eye movement speed were calculated based on endoscopist gaze coordinates in each examination. Time required for observation and treatment of polyps was excluded. The lower peripheral area was defined as the bottom row when the screen was divided into 6×6 sections. These parameters were compared between patients with and without adenomas.

Five physicians performed 158 colonoscopies. The adenoma detection group exhibited a lower peripheral gaze rate (13.7% vs. 9.5%,
P
= 0.004) and smaller average eye movement distance (29.9 pixels/30 ms vs. 33.3 pixels/30 ms,
P
= 0.022). Logistic regression analysis showed that a lower peripheral gaze rate > 13.0% and an average eye movement distance <30 pixels/30 ms were increased independent predictors of adenoma detection (
P
= 0.024, odds ratio [OR] 2.53, 95% confidence interval [CI] 1.71-3.28;
P
= 0.045, OR 4.57, 95% CI 1.03-20.2), whereas age, sex, and withdrawal time were not.

Lower peripheral gaze rate and slow eye movement are associated with colorectal adenoma detection.