Diagnosing Glaucoma in the Peripheral Retina
Co-Principal InvestigatorsThasarat Vajaranant, MD
Early diagnosis of glaucoma is important because it leads to more effective treatment. Early glaucoma can affect central vision or peripheral vision, so both areas of vision should be tested. The best objective test for glaucoma evaluates only central vision. Therefore, we developed a test to evaluate peripheral vision so that early detection is available to everyone. This project will give the central vision and peripheral vision tests to a group of glaucoma patients, to show that the new peripheral vision test helps to diagnose the disease.
The goal of this project is to evaluate a new testing technology for early diagnosis of glaucoma; this new approach looks for early signs of glaucoma in areas of the retina that are beyond the scope of traditional testing.
In Specific Aim 1, we will obtain test results from 25 patients with mid-stage glaucoma, 25 patients with early-stage glaucoma, and 25 glaucoma suspects (along with 75 normally-sighted subjects for comparison). These results will allow us to make a quantitative comparison between our new test and the conventional tests. In Specific Aim 2, we will apply an analysis strategy to our testing results that should significantly boost sensitivity to the earliest effects of glaucoma. This strategy exploits the fact that early glaucoma-related dysfunction is localized, as opposed to being uniformly spread across the retina.
The unique aspect of this work is the testing technology, which was developed in my lab. We use a custom-built three-dimensional screen to present a precise visual stimulus in the peripheral visual field of the test subject. This allows us to evaluate the health of the peripheral retina, where damage often begins but is missed by conventional testing (which focuses on the central retina).
At the end of this study, we will have the first meaningful evaluation of the importance of peripheral retina testing in glaucoma. In our early results, one third of patients had more dysfunction in the peripheral retina than in the central retina; this implies that one third of glaucoma patients might be diagnosed earlier if peripheral retina testing is included in routine exams. Earlier diagnosis would result in earlier management and greater preservation of sight for many patients.