Abstract
Purpose :
Recent advancements in therapies for inherited retinal diseases offer promising improvements in patient quality of life, necessitating quantifiable measures of these benefits through the development of performance outcomes (PerfOs). This research addresses the challenge of optimizing PerfOs’ precision with tasks mirroring daily activities and meaningful for the patient. This study validated a PerfO using a visual search task in virtual reality (VR, ViSA-VR) with naturalistic scenes. Employing a prospective and longitudinal approach, including test-retest and one-year follow-up, we compared the visual search performance and visual function of retinitis pigmentosa (RP) patients and healthy volunteers (HV).
Methods :
In this study, immersed in VR, thirty RP patients and thirty age-matched HV searched for two spherical targets in various scenes. Participants completed the task two times, at day one (D1) and after one year (Y1). The performance score was calculated combining the response times and the success rate of each search. Concurrently, we conducted ophthalmological follow-ups of the participants, monitoring changes in visual acuity (VA), contrast sensitivity (CS) and visual field (VF) area over the one-year period.
Results :
In the RP group, the results revealed strong to moderate correlations between the performance score and all visual variables: VA at D1 (r=-.75) and at one year (r=-.65), CS at D1 (r=-.82) and Y1 (r=-.71), and the VF area from Goldmann III4 perimetry at D1 (r=-.54) and Y1 (r=-.50). Over the one-year period, both visual function and performance score remained stable (all p>.50). The one-year reliability, measured by intraclass correlations (ICC), was excellent and comparable across the performance score (ICC=.98), VA (ICC=.98), CS (ICC=.88), and VF area (ICC=.99).
Conclusions :
The observed stability in visual function among RP patients corresponds with the slow deterioration reported in the literature, typically less than 10% per year for VF and less than one letter per year for VA. The one-year reliability of the performance score mirrors the progression of the disease. The one-year reproducibility of the performance score parallels that achieved with standard visual measurements. Finally, the high level of correlation between the performance score and the CS shows that ViSA-VR is relevant for measuring therapeutic benefits in interventional studies.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.