NPDR, commonly known as background retinopathy, is an early stage of diabetic retinopathy. In this stage, tiny blood vessels within the retina leak blood or fluid. The leaking fluid causes the retina to swell or form deposits called exudates.
Many people with diabetes have mild NPDR, which usually does not affect their vision. When vision is affected it is the result of macular edema and/or macular ischemia.
Macular ischemia occurs when small blood vessels (capillaries) close. Vision blurs because the macular no longer receives sufficient blood supply to work properly.
PDR is present when abnormal new vessels (neovascularization) begin growing on the surface of the retina of the optic nerve. The main cause of PDR is widespread closure of retinal blood vessels, preventing adequate blood flow. The retina responds by growing new blood vessels in an attempt to supply blood to the area where the original vessels closed.
Unfortunately, the new abnormal blood vessels do not resupply the retina with normal blood flow. The new vessels are often accompanied by scar tissue that may cause wrinkling or detachment of the retina.
It may take days, months, or even years to reabsorb the blood, depending on the amount of blood present. If the eye does not clear the vitreous blood adequately within a reasonable time, vitrectomy surgery may be recommended. Vitreous hemorrhage alone does not cause permanent vision loss. When the blood clears, vision may return to its former level unless the macular is damaged.
Tractional retinal detachment: When PDR is present, scar tissue associated with neovascularization can shrink, wrinkling and pulling the retina from its normal position. Macular wrinkling can cause visual distortion. More severe vision loss can occur if the macula or large areas of the retina are detached.
Neovascular glaucoma: Occasionally, extensive retinal vessel closure will cause new, abnormal blood vessels to grow on the iris (colored part of the eye) and in the drainage channels in the front of the eye. This can block the normal flow of fluid out of the eye. Pressure in the eye can build up, resulting in neovascular glaucoma, a severe eye disease that causes damage to the optic nerve.
A medical eye examination is the best way to detect changes inside your eye. An ophthalmologist (Eye M.D.) can often diagnose and treat serious retinopathy before you are aware of any vision problems. The ophthalmologist dilates your pupil and looks inside the eye with special equipment and lenses.
If your ophthalmologist finds diabetic retinopathy, he or she may order color photographs of the retina or a special test called a fluorescein angiography to find out if you need treatment. In this test a dye is injected into your arm and photos of your eye are taken to detect where fluid is leaking.
Medical Treatment: In certain cases, your Eye M.D. may choose to treat your macular edema with injections of medicine in your eye. These special shots of medicine–called intravitreal injections–may be steroids or other medications. They are designed to shrink the swelling of the macula.
Vitrectomy: In advanced PDR, your ophthalmologist may recommend a vitrectomy. During this microsurgical procedure, which is performed in operating room, the blood-filled vitreous is removed and replaced with a clear solution. Your ophthalmologist may wait for several months to see if the blood clears on its own before performing a vitrectomy.
Vitrectomy often prevents further bleeding by removing the abnormal vessels that caused the bleeding. If the retina is detached, it can be repaired during vitrectomy surgery. Surgery should usually be done early because macular distortion or tractional retinal detachment will cause permanent visual loss. The longer the macula is distorted or out of place, the more serious the vision loss will be.
If you need to be examined for eyeglasses, it is important that your blood sugar be consistently under control for several days when you see your ophthalmologist. Eyeglasses that work well when blood sugar is out of control will not work when blood sugar is stable.
within a few months of the diagnosis if you are 30 years old and older.
Diabetic Retinopathy. A Closer Look. (2007). American Academy of Ophthalmology. San Francisco.