Wills Eye retina doctors are leading experts in the treatment of diabetic retinopathy with the latest clinical trials and new therapeutic approaches for this disease.
Diabetic retinopathy is a complication of diabetes, a condition in which the blood sugar level is elevated because the body is unable to use or make enough insulin, or cannot use it as well as it should, and this affects how sugar is used for the body's energy. This high sugar content damages blood vessels in the body over time and can affect a variety of body organs such as the eyes, heart, and kidneys.
Diabetes affects the eyes by causing damage to blood vessels in the retina. Breakdown of retinal blood vessels may result in fluid leaking into the center of the retina (macular edema) or abnormal blood vessels that grow on the surface of the retina (neovascularization) which can bleed and create scar tissue. This can lead to loss of vision.
The longer someone has diabetes mellitus, the more likely they will develop diabetic retinopathy. After 25 years, nearly all people with diabetes mellitus will show some signs of diabetic retinopathy. The severity of diabetic retinopathy is also related to blood glucose (sugar) and blood pressure control. Keeping blood glucose levels down to as normal as possible reduces the degree and rate of progression of diabetic retinopathy and other diabetic complications in the body.
• Gradual, progressive blurring of vision
• Sudden, severe vision loss
• Fluctuating vision
It is very important that people with diabetes mellitus undergo at least an annual eye exam by an ophthalmologist, whether or not they have any vision symptoms. It is important to remember that diabetic retinopathy may progress and not cause any symptoms. It is also very important for people to understand that their blood glucose (sugar) control should be as good as possible with the goal of keeping the hemoglobin A1C level at a target level set by the physician guiding the treatment of the blood sugars.
There are two major types of diabetic retinopathy: non-proliferative and proliferative.
Non-Proliferative Diabetic Retinopathy is the earlier stage and most common form of this disease and is characterized by visible damage to small retinal blood vessels. These blood vessels may develop balloon-like swelling called microaneurysms. Microaneurysms and other areas of abnormal retinal blood vessels may leak fluid, causing the retina to swell or bleed. This may lead to vision loss. Leakage in the center of the retina (macula), known as macular edema, is the most common mechanism of vision loss in people with diabetic retinopathy.
Some people develop a more advanced stage of diabetic retinopathy. This occurs when the small blood vessels that deliver oxygen to the retina get damaged, and the body makes new, abnormal blood vessels (neovascularization). These abnormal blood vessels are fragile and can bleed and pull on the retina as they grow. Bleeding into the vitreous cavity of the eye (vitreous hemorrhage) can result in sudden and sometimes severe loss of vision. This type of hemorrhage is painless and, early on, may be seen as cobweb-like floaters in one’s vision. New floaters and any sudden vision change in a person with diabetic retinopathy should be evaluated promptly by an ophthalmologist.
Proliferative diabetic retinopathy can also lead to traction retinal detachments. The retinal neovascularization can grow to be large and then contract, pull, and lift the retina. Retinal detachment can lead to loss of vision if it involves the macula.
Medicines injected into the eye such as anti-VEGF drugs (eg. Lucentis, Eylea, Vabysmo, and Avastin) and steroids (eg. Triamcinolone, Ozudex, and Iluvien) are now commonly used to treat diabetic macular edema and some of the proliferative manifestations of the condition. The anti-VEGF agents are generally considered first line therapy for treating most cases. Repeat injections may be necessary for long-term control of the retinopathy.
People with diabetic retinopathy may require vitrectomy surgery in an operating room setting. A vitrectomy is performed when there is bleeding or retinal traction that is causing loss of vision in people with advanced diabetic retinopathy. In this surgical procedure, small instruments are inserted into the eye under microscopic visualization, and both the vitreous hemorrhage and any scar tissue are removed. Laser photocoagulation may be performed at the time of surgery, and in some cases, a gas bubble or silicone oil may be placed to hold the retina in position if there are retinal holes or detachment. The prognosis for people who require vitrectomy surgery depends upon the status of the underlying retina.
Laser photocoagulation is a well-established treatment for diabetic retinopathy. A laser delivers a split-second burst of intense light energy to treat leaky retinal blood vessels or promote shrinkage of abnormal blood vessels (neovascularization). Laser photocoagulation has been proven in large clinical trials to significantly reduced the risk of both moderate and severe vision loss in people with diabetic retinopathy.
In general, laser treatments are intended to stabilize or prevent progression of various diabetic retinopathy complications and may or may not result in any noticeable vision improvement. The best results with the best chances of preserving a good level of vision are achieved with optimal sugar control and early detection and treatment of diabetic retinopathy-related problems. Lastly, laser treatments may not work in everyone and other treatments (below) may be needed.
Wills Eye Retina specialists are in the forefront of research efforts, participating in multiple clinical trials to investigate new forms of treatment for diabetic retinopathy and a variety of other retinal conditions.
These new medical compounds are being studied to determine their efficacy and safety in comparison to the current standard anti-vascular endothelial growth factor (VEGF) agents. Administered by intravitreal injection, they may potentially achieve a longer therapeutic effect.
These technologies utilize different non-disease-causing viral vectors to carry and deliver a coding sequence for a soluble anti-VEGF protein. In essence, the goal is for anti-VEGF medication to be manufactured by cells in the eye, which will hopefully reduce the need for frequent intravitreal injections.