Diabetic Retinopathy
What is Diabetic Retinopathy?
Diabetic retinopathy is the most common cause of blindness in patients between 24 and 70 years old.
Diabetes affects not only the blood sugar level but also causes damage to small blood vessels throughout the body. These changes occur very gradually and become more common as a person has had diabetes for a longer period of time. Because a person with early diabetes may have no symptoms, one may have had the eye condition for several years before it is diagnosed.
With time, the circulation to the kidneys, the peripheral nerves, the feet, the heart, and the eyes are especially affected. If you have numbness, tingling, or loss of sensation in the feet, it is likely that you are beginning to have what is referred to as peripheral neuropathy. This means there is damage to peripheral nerves from reduced blood supply. Often, when a person has neuropathy, they may have diabetic retinopathy as well.
Initially, people do not experience pain or discomfort when living with diabetic retinopathy. By the time symptoms develop, the degree of retinal damage can be quite extensive. If you are diabetic, the American Academy of Ophthalmology recommends that you have your eyes dilated with drops and the retina examined at least annually.
Non-Proliferative Diabetic Retinopathy
There are two basic stages of diabetic retinopathy. These are “background” or “non-proliferative” diabetic retinopathy (NPDR) and “proliferative” diabetic retinopathy (PDR). The non-proliferative form is the earlier form, and the proliferative stage is the more advanced stage. In the non-proliferative forms, the small capillaries in the back of the eyes develop tiny bulges called microaneurysms.
In these spots, the walls of the vessels are weakened, and they leak a clear plasma-like fluid. This may make the retina wet and swollen, a condition known as “edema.” If the center of the retina is affected, as it usually is, the condition is known as macular edema.
Proliferative Diabetic Retinopathy
The “proliferation” refers to the growth of abnormal new blood vessels, which grow in the back of the eye, like weeds, where they’re not supposed to grow. These blood vessels are weak and can break and bleed, causing vitreous hemorrhage and “floaters.” Floaters are spots floating in the vision. If the bleeding is more severe, the entire inside of the eyeball can be filled with blood, partially or totally blocking vision.
Treating Diabetic Retinopathy in Atlanta
Macular edema can often be helped with a treatment known as focal laser treatment to attempt to seal off points where leaking is occurring. When the leakage is more diffused, sometimes a grid pattern of laser treatment is done. Laser eye surgery is a non-invasive treatment done in the office in which there are no incisions or cutting and no stitches. Numbing eye drops are used to ensure comfort during the procedure. This treatment results in an improvement in vision about 20-25% of the time. Rather than being used to improve vision, it is mainly used to stabilize vision and reduce the chances that vision will worsen because of macular edema and diabetic retinopathy.
The proliferative form of the disease is treated with a different kind of laser eye surgery known as panretinal photocoagulation (PRP). This treatment involves a greater number of applications and is sometimes done in two or three separate sessions. The peripheral portion of the retina is treated, which can cause side effects such as constriction of the visual field, as well as reduction in night vision. These side effects are relatively uncommon, and when they occur, are necessary tradeoffs to attempt to preserve the central vision.
In the event that there is severe hemorrhage into the vitreous (the clear gel that fills the central cavity of the eye), surgery can be done to remove the vitreous jelly and the blood. This is known as vitrectomy surgery. This type of surgery may also be required if the abnormal blood vessels in the back of the eye form scar tissue, which pulls on the retina. This scar tissue may pull hard enough to lift the retina off the back of the eye like a tent. This situation is called a tractional retinal detachment.
There are some medications that can be injected into the eye that are beneficial to those with diabetic macular edema and proliferative diabetic retinopathy. Current studies are underway that will bring to market newer medications that can be injected into the eye to help reduce or resolve diabetic macular edema.
With education, careful follow-up, and tight management of blood sugar, as well as early laser treatment when needed, most blindness from diabetes can be prevented.
