Eye tracking and virtual reality in the rehabilitation of mobility of hemianopia patients: a user experience study

Purpose: To test the usability of eye tracking and virtual reality during vision rehabilitation training of hemianopia patients. Methods: Individuals with hemianopia (n = 13) and normal-sighted controls (n = 4) performed various exercises that are commonly used in vision rehabilitation for mobility, while wearing a head-mounted eye tracker or a head-mounted virtual reality (VR) display. Occupational therapists (n = 4) guided them through the exercises. All participants (including therapists) filled out a questionnaire, assessing their experience with the used device. Individuals with hemianopia were split into three groups according to their stage in vision rehabilitation therapy and performed 1 (beginner), 2 (intermediate) or 3 (advanced) different exercises. Results: Individuals with hemianopia rated the mobile eye tracker with a score of 3.97 ± 0.5 points (beginner), 3.8 ± 0.5 points (intermediate) and 4 ± 0 points (advanced) the corresponding occupational therapists with a score of 3.6 ± 0.6, 3.4 ± 0.9 and 3.87 ± 0.6 points (out of a maximum of 4 points). The VR headset was rated with 3.9 ± 0.5 points by individuals with hemianopia, 3.8 ± 0.5 points by normal-sighted controls and 2.5 ± 1.4 points by the occupational therapist in a virtual hallway scenario. In a street-crossing scenario, it was rated with 3.7 ± 0.5 points by individuals with hemianopia, 3.7 ± 0.8 points by controls and 2.8 ± 1.2 by occupational therapists. In a walking along a pavement scenario the individual with hemianopia gave 4 ± 0 points and the controls 3.8 ± 0.4 points on average. Conclusions: Both devices were seen as useful additions to vision rehabilitation therapy, as they enable better feedback to patients and the opportunity to do different exercises at different levels of difficulty.