Comparison of surgeon gaze behaviour against objective skill assessment in laparoscopic cholecystectomy-a prospective cohort study

Abstract

Background: Eye tracking technology may provide the basis of a novel, objective technical skill assessment in surgery. Past research has showed differences in the gaze patterns between expert and novice surgeons. The aim of this study was to investigate the relationship between gaze behaviors and technical skill during laparoscopic cholecystectomy as determined by objective assessment scores.

Methods: Gaze behaviors of surgeons performing laparoscopic cholecystectomies were mapped using wearable eye tracking apparatus. Two impartial surgeons retrospectively analyzed video footage of the procedure to perform Objective Structured Assessment of Technical Skill (OSATS) assessments. Primary endpoints were correlation between gaze behaviours (dwell time (%) and fixation frequency (count/s)) and OSATS scores. Dwell time was defined as the percentage of time spent fixating on particular visual areas of interest (AOI). Pearson's correlation coefficient was used to estimate the relationship between primary endpoints and AOIs. Statistical significance was set at p < 0.05.

Results: 13 procedures were analyzed. Throughout all operative segments, a negative correlation was present between operating theatre dwell time and OSATS scores (p < 0.05). During dissection of Calot's triangle, there was a strong positive correlation between laparoscopic screen dwell time and OSATS scoring [r = 0.655, p < 0.05]. Scrub nurse dwell time during dissection of Calot's triangle showed a strong negative correlation with OSATS scoring [r = -0.619, p < 0.05]. During dissection of gallbladder fossa, operating theatre fixation frequency negatively correlated against OSATS scores [r = -0.566, p < 0.05].

Conclusion: The results suggest a greater focus on significant visual stimuli alongside a lack of attention to non-essential stimuli during critical stages of the operative period is associated with greater technical skill. This aids the validation of eye tracking as an adjunct high-stakes technical skill assessment.

Keywords: Assessment; Eye-tracking; Laparoscopic cholecystectomy.