Evaluating balance control in glaucoma would be more effective within a virtual reality testing environment, according to a report authored by researchers from the University of California and published in Ophthalmology, the journal of the American Academy of Ophthalmology.
The finding is important because people with glaucoma are three times more likely to fall than those without the disease; however research has only found a weak correlation between results obtained by visual field testing and risk of falls in glaucoma patients.
For this research, 42 patients with open-angle glaucoma and 38 healthy subjects were studied by a team of ophthalmologists, vision scientists and engineers. Oculus Rift stereoscopic goggles were worn to simulate different settings while standing on a force platform, which measured balance and movement, including when the goggles simulated movement such as moving through a tunnel or a spinning floor, and when the goggles were not worn or were not providing visual stimulation.
The study showed that people with glaucoma made balance adjustments that were on average 30–40 per cent more pronounced than the balance adjustments made by healthy subjects. Healthy participants were more quickly able to regain balance than those with glaucoma, and the degree to which balance was lost was strongly linked to a history of falls.
Changes in balance control, they proposed, may be related to the loss of retinal ganglion cells caused by glaucoma, which leads to slower visual processing and impaired motion perception.
It is hoped that by using this virtual reality approach, patients at high-risk of falling can be identified and preventative measures implemented at an earlier stage. Researchers also hope that future studies using this paradigm will help ophthalmologists better understand the relationship between risk of falls and retinal ganglion cell loss in people with glaucoma.
