Rambam physician discovers new cause of vision loss in diabetics, testing how to prevent impaired vision

  

Professor Naim Shehadeh, Director of the Institute of Diabetes, Endocrinology and Metabolism at Rambam Health Care Campus and President of the Israel Diabetes Association, hypothesized that although hyperglycemia (abnormally high blood glucose levels) is the major known risk factor for vision complications in diabetics, exposure to sun-light may also be important. Common diabetic symptoms include blurred vision, early onset of cataract and retinal damage that can even lead to blindness - diabetes is the leading cause of new vision loss in working-age adults (20-60 years old) worldwide. Israel is at the cutting edge in diabetes research, with the third highest mortality rate from diabetes among countries in the Organization for Economic Cooperation and Development (OECD), especially in the Israeli Arab population. Many visual problems in diabetics are caused by changes in the lens (cataract) or as a result of damage and reduced function in the light-sensitive lining (retina) at the back of the eye (diabetic retinopathy) followed by changes in the blood retinal barrier due to leaky small blood vessels, retinal swelling and scarring. Since controlling hyperglycemia slows down but does not prevent these visual problems and their progression, other factors must contribute to diabetic cataracts and retinopathy. While our eyes are exposed to a wide spectrum of light during the day, Professor Shehadeh and his Technion team hypothesized that exposure to sun-light may play an important role in the development of eye damage in diabetic patients. They exposed diabetic rats to different light wavelengths from the visible sun-light spectrum and identified the harmful light. The next step was to develop an optic filter that can block and protect the eyes from those wavelengths. Results showed that using the special optic filter glasses significantly decreased light exposure by filtering out the short wavelengths (400–530 nm) thereby reducing eye damage in diabetic rats, and may also benefit non diabetic patients.Professor Shehadeh said the team felt driven as they had nothing to offer diabetic patients with eye damage other than to instruct them to try to control their blood glucose. Human trials will start later this year to test the effect of the optical filters. Prescription and non-prescription sunglasses with colored optic filters will be available in the spring for Israeli consumers. The future goals are to develop colorless filters that will offer the same protection – in glasses, building and car windows…wherever they can slow down or prevent vision loss in diabetics and perhaps non-diabetics.  "This is the essence of Israeli scientific and medical innovation, offering hope to diabetes patients throughout the world at risk of losing the precious gift of sight," said Richard S. Hirschhaut, National Director of the American Friends of Rambam Medical Center.             Professor Naim Shehadeh, Director of the Institute of Diabetes, Endocrinology and Metabolism at Rambam Health Care Campus and President of the Israel Diabetes Association. Credit: RHCC