Real time video-based gaze tracking for detecting subtle deviation angle change in abducens nerve palsy.

Aim: To measure abducens nerve palsy patients' visual angle using real time video-based gaze tracking system.

Methods: This research was a cross-sectional study. The subjects were taken by convenience sampling technique in the Neuro-ophthalmology department at Sardjito General Hospital Yogyakarta, Indonesia, and had met the inclusion and exclusion criteria. The visual angle measurements were performed using an eye tracker with a computer webcam (GENICULA system/Gaze Tracking Artificial Intelligence for Ocular Motor Palsy). The analytical method used was the Mann-Whitney test to compare the visual angle between the abducens nerve palsy group and the healthy eye group. The Wilcoxon test was used to see the significance of differences in visual angle improvement in abducens nerve palsy patients.

Results: A total of 39 subjects participated, with a mean age of 46.54±15.67y; 17 were male and 22 were female. The visual angle was 20.88±3.76 in the abducens nerve palsy group (=39 eyes) and 23.10±2.91 in the normal group (=39 eyes, =0.011). The visual angle improvement of abducens nerve palsy before and after cured was statistically significant (=0.039).

Conclusion: The real time video-based gaze tracking system is easy to use, efficient, and accurate. A slight decrease in visual angle measurement can be detected using this GENICULA system and therefore it is important for diagnosis slight deviation in abducens nerve palsy.