Fact Sheet_1 1 GENERAL INTRODUCTION TO DIABETIC RETINOPATHY What is diabetic retinopathy (DR)? Diabetes mellitus affects blood vessels, especially small ones, of the body, for example. in the eyes (retinopathy), kidneys (nephropathy) and nerves (neuropathy). In the eye, it particularly affects the light sensitive part, the retina. This is called diabetic retinopathy and can lead to blindness if untreated. Who gets DR? Anyone with diabetes, regardless of whether controlled with diet, on pills or on insulin can get it. The longer the duration of the disease, the higher the chance of getting DR. After 20 years of diabetes, about 80% of all patients have some DR. Some patients are at a higher risk of developing DR. Major risk factors include: 1. A longer duration of diabetes 2. Poor diabetic control 3. Poor control of high blood pressure Normal Retina 4. Poor renal functions 正常視網膜 5. High cholesterol level 6. Pregnancy How does DR affect my vision? Diabetic retinopathy causes 2 major problems: 1. 2. Poor blood supply causes a lack of oxygen in the retina, which in turn leads to new abnormal blood vessel formation. (NEOVASCULARISATION) If untreated, this may cause: a) Vitreous hemorrhage b) Tractional retinal detachment c) Neovascular glaucoma Leakage from blood vessels and tissues causes swelling of the central part of the retina (macula), which is essential for clear and sharp vision. (MACULAR EDEMA) It is the main cause of poor vision in diabetic patients. It occurs in about 10% of the diabetic population and in 30% of patients with twenty years or more of diabetes. Preretinal Haemorrhage 糖尿血管增生引致視網膜前出血 Diabetic Macular Edema 糖尿黄斑水腫 Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong June 2004 Fact Sheet_1 2 How do I know whether I have diabetic retinopathy? Because diabetic retinopathy is symptom-free in the early and mid stages, the American Academy of Ophthalmology (AAO) recommends that all diabetics should schedule an eye examination at least once a year, and more frequently if DR is diagnosed. Other specific recommendations include: 1. • When you are first diagnosed with diabetes, you should have your eyes checked: within five years of the diagnosis if you are 29 years old or younger; • 2. within a few months of the diagnosis if you are 30 years old and older. Pregnant women with diabetes should schedule an appointment in the first trimester because retinopathy can progress quickly during pregnancy. How is diabetic retinopathy treated? z Laser: Laser is used in 2 ways a) For neovascularisation: Laser is given to the whole of the retinal except the central macular region. The laser helps to reduce abnormal new blood vessel formation and prevent complications arising from the new blood vessels. b) For the macular edema: Laser is given to the macular region (except the most central part of the macula, called fovea). The main aim of laser treatment is to prevent the vision from getting worse. Very few patients can gain vision in the long run. z Intravitreal triamcinolone: a new treatment for diabetic macular edema. In many case, it can give you some visual gain. However, the long-term results are lacking and repeat injection is needed in most cases. z Surgery may be required to treat complications such as persistent vitreous hemorrhage and retinal detachment. Important Advice: Prevention is better than cure! z z z z z z Regular eye check-ups (or more frequently as instructed by doctor). Good blood sugar control. Stop smoking and good control of other health problems like raised blood pressure and high cholesterol. Regular exercise. Good balance diet, but no specific drug or food item will help. Follow the recommended treatment by your ophthalmologist. Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong June 2004