New research from scientists at UMass Medical School suggests varying blood flow in the retina may enable clinicians to earlier identify patients with obstructive sleep apnea.
Using optical coherence tomography angiography (OCTA), researchers found a correlation between retinal vasculature findings and obstructive sleep apnea. OCTA is a novel imaging technique that displays high resolution images of various blood vessels within the eye without the need to inject a contrast dye. The research, led by Shlomit Schaal, MD, PhD, chair and professor of ophthalmology & visual sciences, and Lauren Lombardi, a first-year medical student at UMMS, is published in the September issue of Retina Today; Lombardi is the lead author on the paper.
“This is a novel area of research that carries the potential to change the way we manage obstructive sleep apnea patients,” said Dr. Schaal.
The possible correlation between obstructive sleep apnea and blood flow in the retina was found as a result of a patient encounter Schaal had prior to the study.
“The patient had a retinal disease called age-related macular degeneration, but she was not responding to therapy as would have been expected. After treating her underlying obstructive sleep apnea, she responded better to her eye treatment, and we were able to save her vision,” Schaal said. The case was published in the journal Retina in April 2016.
The UMMS research team, which also included Omar Helmy, MD, a postdoc in the Schaal Lab; Lotem Nativ, an undergraduate student from UMass Amherst; and colleagues at Baystate Medical Center, used the advanced imaging system in the eyes of patients with severe obstructive sleep apnea, but with no other known eye pathology, to further investigate the potential link.
By performing and analyzing super macular scans, the researchers determined that obstructive sleep apnea patients in the study had, on average, a lower vasculature density in the foveal avascular zone.
Lombardi, who presented the research at the Association for Research in Vision and Ophthalmology Conference in May, said researchers continue to work with Mary Jo Farmer, MD, PhD, and Karin Johnson MD, sleep specialists at Baystate Medical Center who care for high-risk obstructive sleep apnea patients.
“We’ve noticed that in patients with mild sleep apnea you don’t see the changes as much. We’re trying to work with more patients with severe obstructive sleep apnea,” said Lombardi, who hopes to continue working with the Schaal group as part of her UMMS Capstone project.
Schaal and colleagues are also expanding their retina OCTA research to explore new and yet unknown correlations between systemic diseases and retinal blood vessels. For example, they will consider the relationship between multiple sclerosis and the retinal blood vessels with colleagues in the Department of Neurology; the ability to diagnose pre-eclampsia according to the appearance of retinal blood vessels in collaboration with the Department of Obstetrics & Gynecology; and the ability to monitor plaquenil toxicity in rheumatoid arthritis patients in collaboration with the Division of Rheumatology in the Department of Medicine.