Eyes with proliferative retinopathy are at higher risk for vision loss. With narrowing of the vascular walls from incorporation of the AGEs, the blood flow to the retina is compromised, as time goes on. Chemical signals are produced by the stressed tissue, and a complicated “call for help” results in the development of new blood vessels responding to the “need” for oxygen and nutrition. These new blood vessels, or neovascularization, mark an important transition of the diabetic retina into proliferative retinopathy. These eyes are at much higher risk for events that will result in severe visual loss: retinal hemorrhages that break through the surface, vitreous hemorrhages, scarring and contracture of the retina from overlying fibrovascular tissue, resulting in a retinal detachment.
Diabetic cataracts can develop at an earlier age than usual. Detection and treatment is the same as other cataracts. Symptoms might include blur, glare, and loss of color vision.
Diabetic optic neuritis results from the closing of the tiny blood vessels in the nerve and is usually associated with poor circulation elsewhere.
Glaucoma, or elevated eye pressure associated with diabetes, may be the result of new blood vessels (neovascularization) forming in the iris, releasing proteins and blood that clog up the meshwork (see Glaucoma), or causing the meshwork to scar closed. Some studies have indicated that diabetes might be a risk factor for open angle glaucoma (OAG), but others have not.
Diabetic eye disease can often be treated if detected early enough. A yearly, dilated eye exam is a good start. During this exam, the following steps are standard:
Testing of vision and need for glasses
Eye pressure check (tonometry)- to detect glaucoma
Slit lamp exam- to look for signs of glaucoma, cataract, iris neovascularization
Retinal exam- to detect glaucoma, optic nerve disease, diabetic macular edema, and retinopathy
Other eye exams and specialized tests that your eye doctor might be useful in examining the diabetic eye include:
To detect and document subtle changes in the retinal vasculature
Uses a fluorescent dye that is injected into a vein in your arm. As the dye circulates through your eyes, a blue light causes the dye to light up, pinpointing blood vessels that are closed, broken down or leaking fluid.
Optical Coherence Tomography (OCT)
Provides cross-sectional images of the retina that show the thickness of the retina and whether fluid has leaked into retinal tissue. Later, OCT eye exams can be used to monitor treatment effectiveness.
Eye Surgery and Treatment for Diabetic Eye Disease
Treatment for diabetic eye disease depends on the severity of a cataract; the reason for any glaucoma; and on the type of diabetic retinopathy you have, its severity and how well it may respond to specific treatments and/or eye surgery.
Early Diabetic Retinopathy
If you have nonproliferative diabetic retinopathy, you may not need any treatment for years. However, your eye doctor will closely monitor your retina to determine if you need further diagnostic studies, indicating the need for treatment.
Diabetic Macular Edema
Laser is sometimes used for macular edema if a point of leakage can be identified. More recently, there have been exciting advances in the pharmaceutical treatment of macular edema, using injections of a number of different medications into the vitreous cavity to “dry up” the edema.
Advanced Diabetic Retinopathy
If you have proliferative diabetic retinopathy, you may need prompt laser surgery and/or operative surgical treatment. Depending on the specific problems with your retina, options may include:
Focal Laser Eye Surgery
This laser surgery, also known as photocoagulation, can stop the leakage of blood and fluid in the eye. It is usually done in the office. During the procedure, leaks from abnormal blood vessels are sealed with laser burns. Focal laser treatment is usually done in a single session. Your vision will be blurry for about a day after the procedure. Sometimes small spots caused by the laser burns may appear in your visual field. The spots generally fade and disappear with time. If you had blurred vision from swelling of the central macula before surgery, however, you may not recover completely normal vision.
Scatter Laser Eye Surgery
This laser treatment, also known as panretinal photocoagulation, can shrink the abnormal blood vessels. It’s also done in your eye doctor’s office or in an eye center. During the procedure, the areas of the retina away from the macula are treated with scattered laser burns. The burns cause the new blood vessels to shrink and disappear. Scatter laser surgery is usually done in two or more sessions. Your vision will be blurry for about a day after the eye surgery. Some loss of peripheral vision or night vision after the eye surgery is possible.
This procedure can be used to remove blood from the center of the eye (vitreous) and scar tissue that’s tugging on the retina. It’s done in a surgery center or hospital under local or general anesthesia. During the procedure, the doctor makes a tiny incision in your eye. The blood-filled tissue and scar tissue are removed with delicate instruments and replaced with a salt solution, which helps maintain your eye’s normal shape. Sometimes a gas bubble must be placed in the cavity of the eye to help reattach the retina. After surgery, you may stay in the hospital overnight. If a gas bubble was placed in your eye, you may need to remain in a facedown position until the gas bubble disappears – often several days. You’ll need to wear an eye patch and use medicated eyedrops for a few days or weeks. Often, vitrectomy is followed or accompanied by laser surgery.
Laser surgery often slows or stops the progression of diabetic retinopathy, but it’s not a cure. Because diabetes is a lifelong condition, future retinal damage and vision loss is possible. Even after laser eye surgery for diabetic retinopathy, you will need regular eye exams. At some point, additional treatment and/or eye surgery may be recommended by your ophthalmologist.