What is Diabetic Retinal Disease?
With the recent increased incidence of diabetes in the general population, the potential for serious vision loss due to diabetes has increased also. Diabetes can cause several ocular complications and the most vision threatening complication is diabetic retinopathy (disease of the retina due to diabetes). Most diabetic patients will develop some amount of mild retinopathy over decades of having the disease. However some patients will develop severe retinopathy resulting in potential severe vision loss.
The retina is a very important tissue which lines the inside of the inside of the eye like wallpaper and acts as the film in the camera for your vision. It is a very vascular tissue, requiring significant blood supply to function properly.
In diabetic patients, the improper breakdown of glucose causes an excessive amount of ketones to accumulate in the blood. These ketones are a very reactive compound and damage the capillary beds that feed the retina causing retinal ischemia (lack of blood supply) and retinal damage. The starving retina sends out chemical mediators calling for increased blood supply and new blood vessel growth to feed it. This process of new blood vessel growth in the retina is called proliferative diabetic retinopathy and may appear to be the retina trying to fix itself which should be helpful but actually has a negative effect. These small new blood vessels are very weak and leak blood and other substances into the retina causing retinal hemorrhages, retinal detachments and subsequent vision loss which can be severe.
Uncontrolled new blood vessel growth can also cause a particular type of glaucoma termed neovascularization glaucoma which is visually devastating. This occurs when new blood vessels grow into the eye’s outflow channels and cause a complete blockage of outflow and the eye pressure will very quickly rise to dangerous levels resulting in a blind painful eye.
Signs and Symptoms of Diabetic Retinal Disease
Initial symptoms of diabetic eye disease are blurry areas in your vision or a sudden change in your glasses prescription. However, once you notice symptoms the disease may already be advanced.
How is Diabetic Retinal Disease Diagnosed?
Your doctor will dilate your pupils to obtain a full view of the retina. Photo documentation of the retina is also highly recommended. If retinopathy is noticed, fluorescein angiography may be performed to identify areas of leaking blood vessels.
How is Diabetic Retinal Disease Treated?
Better control of diabetes will reduce the risk of diabetic retinopathy but if significant new blood vessel growth is found, treatment is required. Panretinal Photocoagulation (fancy word for laser treatment) is a procedure in which certain areas of the starving retina are lasered and effectively killed. This leaves less retina to feed and will hopefully result in an end to the new blood vessel growth. If a patient has a significant retinal bleed, a procedure called a vitrecomy can be performed to clear the blood. Some patients may also benefit from blood vessel growth inhibiting medications which must be directly injected into the eye. Although this may sound scary, the injections are painless and very effective.
What Steps Should I Take If I Think I Have Diabetic Retinal Disease?
All of these conditions sound quite ominous but the good news is that in the last decade we have seen less diabetic eye complications as better treatments, blood glucose monitoring, and patient awareness have led to better control of diabetes. Regardless, diabetic patients should have a full eye examination annually with dilation of pupils to allow for inspection of the entire retina. Early detection of diabetic eye disease is crucial. Also, the eye is a “window into the body” and what’s happening inside the eye is happening all over the body. Hence advancing diabetic eye disease is usually an indicator that the diabetes is damaging other parts of the body as well.
Dr. Reinders has 22 years experience in diabetic eye disease. The sooner he can check your eyes, the better. All doctors agree that waiting and hoping it will get better is not a prescription for success.