Virtual reality and augmented reality headsets have been taking the video game market by storm, allowing players to immerse themselves into new worlds and interact freely with games from their living rooms. Now that the technology is advancing, eye-care researchers and technology companies are beginning to figure out new ways to develop these devices to benefit the lives of patients with age-related macular degeneration.
VR vs. AR
Many people who’ve tested head mounted displays understand the difference between VR and AR, but there are also differences to how these technologies impact AMD patients.
“Virtual reality technology helps you immerse with the virtual world of your interest in which you’re not connected to the real world,” explains Sarika Gopalakrishnan, PhD, a post-doctoral research fellow at Envision Research Institute. “Augmented reality is very different. That helps enhance the view of the real world, which is incorporated in most of the electronic vision enhancement systems for low vision.” Although Dr. Gopalakrishnan prefaces that AR technology devices control the majority of the wearable electronic vision enhancement system (wEVES) landscape, there are devices with VR capabilities that can benefit patients with AMD.
“The lines between VR and AR are blurring as new devices come along, but typically VR produces a wider field of view and a brighter image than AR-style devices,” says Andrew Miller, MS, a post-graduate researcher for the Vision and Hearing Science Research Center at Anglia Ruskin University in Cambridge, UK. “These features are clearly of potential benefit to people with vision impairment.”
There may be a reason for why most wEVES use AR technology rather than VR. “VR-style devices tend to be heavier and are often housed in an enclosed headset compared to a much lighter and more open AR equivalent,” says Dr. Miller. “The weight of the VR devices has been shown by others to be off-putting and a cause for abandonment of wEVES. When we showed devices to people with AMD, we found a very similar initial response with people questioning if they would be able to use them for anticipated tasks as well as thinking their appearance was strange and off-putting rather than high-tech.”
wEVES and Ocular Diseases
It should be understood that wEVES aren’t solely marketed towards AMD. Rather, they can be used for a number of low-vision conditions and pathologies. “My research work has proved that these augmented reality devices not only help people with AMD, but with most of the ocular conditions that cause low vision,” says Dr. Gopalakrishnan. “So, most of these head-mounted displays are designed with a wide range of magnification, variable contrast, adjustable brightness, different viewing modes, along with image enhancements, which help the eye to process the same images much easier. That’s how these devices are helpful for anyone with low vision. These devices are helping people perform their vision functions more efficiently and independently.”
In one of her studies, Dr. Gopalakrishnan has found that these devices work well for patients with cone dystrophy, retinitis pigmentosa and optic atrophy along with AMD.1 She explained that most devices in Western countries are marketed towards AMD, but these devices also provide comprehensive lists online for all ocular conditions that could benefit from the use of wEVES. For example, eSight lists the following conditions on their website:
- cataracts;
- central vision loss;
- cone rod dystrophy;
- diabetic retinopathy;
- diabetic vision loss;
- glaucoma;
- legal blindness;
- macular degeneration;
- ocular albinism;
- optic atrophy;
- optic nerve hypoplasia;
- retinopathy of prematurity; and
- Stargardt disease.
Research has shown that wEVES may benefit a low-vision patient’s visual acuity. In Dr. Gopalakrishnan’s study on the role of head-mounted augmented reality devices on improving visual functions of individuals with low vision, she observed 100 patients with ocular conditions presented earlier in this article.1 The patients’ distance visual acuity improved from 1.1 (0.7) to 0.15 (0.6) logMAR when using an AR device. Also, their near vision improved from 0.6 (0.7) to 0.3 (0.1) logMAR and their visual function score improved from 0.35 (0.26) to 1.89 (1.90).
“We need to be clear in understanding that these devices aren’t a replacement treatment for AMD or any other disease,” cautions Dr. Gopalakrishnan. “So, people need to follow the advice from their ophthalmologist to control the progression of their ocular condition, including AMD. Medical treatment, or surgical treatment, is the first level of treatment. These devices aren’t considered to be treatment options. These are additional enhancement devices. If nothing works for them, either surgically or medically, and the ophthalmologist has tried their best to improve their patient’s vision, but it’s not at 100 percent, then to fill that gap, these devices can help make it 100 percent.