Affecting 4% of the U.S. population, strabismus, commonly known as crossed eyes, results in blurry vision, double vision, eye strain, headaches, and a loss of binocular vision. In severe cases, or left untreated, strabismus can transition to ‘lazy eye’, which is the brain’s adaptation of ignoring signals from the affected eye. Current treatments include eye patch therapy and surgery, which can be painful, impose financial burden, and fall short of effectively treating the condition.
VER offers a therapeutic treatment option for strabismus patients. Virtual reality (VR) technology is currently utilized in other ocular therapies, but this technology has not been applied to strabismus. Our software restores binocular vision to the user by utilizing their desired focal point and translating the image appropriately to the strabismus-affected eye on the OLED screen. The desired focal point is acquired through the eye-tracking capabilities of the Vive Pro Eye VR system. This system was chosen based on its ability to track both eyes independently instead of solely aggregating the approximate eye data.
Created by an undergraduate team of systems, electrical, and computer engineering students at the University of Pennsylvania, the corrective software is built in Unity, and proof-of concept data has shown this solution can improve strabismic patients’ vision. Current work involves further validation testing with hardware integration. Future instantiations of the design will require GPU based computation rather than the current CPU based computation to allow the software to run with a processing latency under 30 milliseconds. This design limitation is due to project constraints concerning the ownership of the GPU API for the hardware system and the University of Pennsylvania’s senior design budget.
Strabismus surgery costs $8,000 on average with insurance, which does not include the after care and necessary follow-up appointments. Eye patch therapy costs vary depending on the rigor of the schedule and whether vision-impending drops are required for the dominant eye. Other home VR optical training device packages charge $8,000, and are not designed for strabismus correction nor are always ophthalmologist recommended. Due to inadequate and expensive treatment options for strabismus patients, there is an apparent need in the market with established opportunity for adoption and success within the therapeutic field.
The future development of VER would allow ophthalmologists to administer the therapy in-office by tuning a correction parameter to increase the involvement of the non-dominant eye. Overtime, this correction parameter would be decreased as the muscles in the affected, weak eye become stronger and develop, treating strabismus through a less painful patient process.