Eye-tracking for low vision with virtual reality (VR): testing status quo usability of the HTC Vive Pro Eye

Background: Adding an eye tracker inside a head-mounted display (HMD) can offer a variety of novel functions in virtual reality (VR). Promising results point towards its usability as a flexible and interactive tool for low vision assessments and research of low vision functional impairment. Visual field (VF) perimetry performed using VR methodologies evidenced a correlation between the reliability of visual field testing in VR and the Humphrey test. The simulation of visual loss in VR is a powerful method used to investigate the impact and the adaptation to visual diseases. The present study presents a preliminary assessment of the HTC Vive Pro Eye for its potential use for these applications. Methods: We investigated data quality over a wide visual field and tested the effect of head motion. An objective direct end-to-end temporal precision test simulated two different scenarios: the appearance of a pupil inside the eye tracker and a shift in pupil position, known as artificial saccade generator. The technique is low-cost thanks to a Raspberry Pi system and automatic. Results: The target position on the screen and the head movement limit the HTC Vive Pro Eye9s usability. All the simulated scenarios showed a system9s latency of 58.1 milliseconds (ms). Conclusion: These results point towards limitations and improvements of the HTC Vive Pro Eye9s status quo for visual loss simulation scenarios and visual perimetry testing.