Surgeons perform more proactive eye movements than novices when performing laparoscopic surgery

Bin Zheng, MD, PhD, Xianta Jiang, Msc, Geoffery Tien, Msc, M. Stella Atkins, PhD

University of Alberta

Objective:
Eye-tracking studies reveal more and more evidence of surgeons’ expertise level. Novice surgeons often track the movement of surgical instruments while more experienced surgeons focus their gazes on the operating target. Proactive eye movement has been recognized as a behavioral marker closely associated with skill expertise. In this study, we decided to investigate whether experienced surgeons perform more proactive movements in performing laparoscopic tasks.

Study Design:
We recorded eye-tracking data from twelve subjects performing a laparoscopic task involving 9 sub-steps. Six of the subjects are surgeons with extensive laparoscopic experience; six are office staff with no surgical experience. Each subject was required to perform 5 trials on identical tasks. The eye gazes of the subjects were also recorded during their performance and overlaid with the synchronized task videos during analysis. We analyzed the videos manually and located the times where the subject’s saccadic movements commenced for every sub-task during task performance and where the tool movement commenced during performance.

Results:
Six surgeons performed a total of 30 trials giving 270 chances to observe proactive eye movement. The same data was collected from novices. On average, surgeons performed the task faster than the office staff (24 s vs 40 s, P = 0.010). We also found that the surgeons performed significantly more proactive eye movements to the target than the staff (64% vs 17%, P < 0.001). The mean offset between proactive eye and hand movement was 168 ms.

Conclusion:
The early onset of gaze on the target in task performance provides visual guidance for hand movement which allowed surgeons to perform the task with increased accuracy and speed. In addition to the “tool-tracking” behavior, the proactive eye motion provides another behavioral marker for us to assess surgeons’ expertise by checking their eye-hand coordination skills.

Session: Poster Presentation

Program Number: P388