A brief overview of some of the conditions that may affect the eye and the treatments available:
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Age-related macular degeneration (AMD) — This chronic disease occurs when macular tissue deteriorates with age. The result can be blurred central vision and possibly a blind spot in your central field of view. Initially, changes due to AMD are seen as small deposits (drusen) that form in the macula area. Often, this dry phase of the disease progresses very slowly.
In some people, as disease progresses, a complication called wet disease develops. This occurs when abnormal blood vessels grow under the retina. Vision loss is usually rapid and severe in wet disease because the retina's light-sensitive cells are damaged. Central vision may be reduced or lost.
There are steps that may help slow the progress of dry AMD. High blood pressure is associated with more rapid progression of AMD. Smoking is associated with worse disease and greater risk of vision loss. A large, multi-center study found that vitamins and minerals appear to slow disease progression in people with intermediate and advanced AMD. Risk of progressive vision loss was reduced by about 25 percent when a combination of vitamins C and E, beta-carotene and zinc were taken.
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Retinal detachment — This may occur with age when changes in the vitreous — shrinkage and
liquefication — cause it to sag or separate from the retina. A strong enough pull may tear the retina and even lead to the retina peeling away from the back of the eye.
Although painless, the signs of detachment of the retina include the sudden appearance of flashes of light followed by what appears to be spots, specks, hairs or strings(floaters). If you experience these visual changes, it is vitally important to see an eye doctor immediately. Without emergency treatment, tearing or detachment of the retina may result in partial or possibly total vision loss. Treatment for retinal tears or detachment may include the use of lasers, or prompt surgery in an operating room.
Diabetic retinopathy — This serious complication of diabetes is
marked by swelling of the retina and progressive leakage or withering of tiny retinal blood vessels. If there is enough blood vessel damage, abnormal vessels may grow from the retina into the vitreous fluid. Sudden vision loss may occur if these abnormal vessels rupture and bleed into the eye. Retinal tears and detachment may also occur.
Immediate medical care is needed if you experience blurred vision, vision loss, sudden appearance of numerous floaters or specks in your vision, sudden flashes of light, or a dark spot in the center of your vision. Laser treatment or surgery to remove the vitreous fluid, which the body eventually replaces with a clear fluid, may be necessary. Careful management of diabetes to control blood sugar levels can delay the onset and slow the progression of retinopathy in the long term.
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Macular Hole — Shrinkage and movement of the vitreous can result in the formation of a hole in the center of the retina, known as a macular hole. The fluid which has replaced the vitreous gel in many areas may then seep through the hole, causing a localized separation of the retina centrally. This process results in a defect or dark spot in the central vision with distortion and central vision loss resulting.
Symptoms of a macular hole include: decreased central vision for both distance and reading activities, distortion in central vision or a small defect in the central vision where small letters may disappear.
Until recently, very little could be done to correct the visual deficit resulting from macular holes. As a result of the introduction of microsurgical techniques, it is now possible to offer a surgical procedure with the potential for some visual improvement. This procedure is known as a vitrectomy, and involves the microscopic removal of the vitreous gel within the center of the eye. Particular attention is paid to removing any of the vitreous attachments from the macula, thus releasing the traction or pulling on the retina which caused the macular hole initially. This permits settling of the retina against the wall of the eye.
Macular Pucker — With age, mobilization and migration of cells found within the retina may spread outward along the surface of the central retina forming a macular scar. This thin layer of scar tissue is known as a macular pucker. Macular pucker is known by a variety of names, including epiretinal membrane, surface wrinkling retinopathy, cellophane retinopathy, and internal limiting membrane disease. All of these names relate to the fact that there is a layer of thin scar tissue on the surface of the macula which result in mechanical wrinkling and distortion of the retina. Since the scar cells are attached to the retina, the retina itself becomes wrinkled in association with the progression of the scar. When this occurs in the central, critical portion of vision, the macula, visual symptoms may result.
The symptoms of a macular pucker include: distortion in lines or letters while reading, a decrease in central vision for distance and reading activities, and blurring or distortion of images when looking at television or in the theater. In most cases, no treatment is recommended for macular pucker. In some instances, however, consideration for surgical repair may be entertained. Repair of a macular pucker or epiretinal membrane is accomplished through use of a vitrectomy, the microscopic removal of vitreous gel from the center of the eye. Particular attention is paid to removing any vitreous attachment to the central macular region.