This month’s Case Study is presented by DIABETES HEALTH’s Eye Care Adviser, Everett Ai, MD. Dr. Ai is the director of the Retina Unit at the California Pacific Medical Center in San Francisco.
My patient was a 21-year-old female who had been diagnosed with type I diabetes at the age of ten. In 1981 she was enrolled in the Early Treatment of Diabetic Retinopathy Study (ETDRS). This study was designed to investigate the use of laser therapy in the prevention of diabetic retinopathy. In the previous year, she had been hospitalized with diabetic ketoacidosis, and she was felt to be a good study candidate.
Within three years of entering the study, she developed marked diabetic retinal changes in both eyes with extremely severe proliferative (advanced) disease and macular edema, a form of tissue swelling, in both eyes. This resulted in decreased vision in her right eye to 20/400 (equivalent to seeing only the big E at the top of the eye chart). As part of the study protocol, the right eye was chosen for experimental laser treatment. Numerous laser applications were delivered to the right eye.
Some of these treatment sessions were rather lengthy in nature. Nevertheless, she continued with the study and, over time, showed a dramatic response to laser treatment. Her vision eventually returned to 20/20 in the right eye.
Nearly 15 years later she continues to see 20/20 in the previously affected eye. Her excellent response to treatment is a testament not only to the importance of timely laser treatment, but also to the optimal control she has gained over her diabetes. This is very critical at this juncture in her life. With the help of this patient and other ETDRS study participants, the form of laser therapy she received was proven to be of great benefit in counteracting retinopathy. Laser treatments are now given worldwide.
As an interesting footnote, after the numerous laser sessions necessary for treatment, her vision would often be temporarily blurry. As a result, it was difficult for her to clearly read the bus signs when returning home after each visit. After one such visit she asked a stranger at the bus stop to help her make out the signs. She eventually got to know this individual, and several years later they were married.