Retinal Detachment and Vitreous Surgery
The eyeball is a hollow organ connected to the brain by the optic nerve. On entering the eye, the optic nerve spreads out in a thin layer of nervous tissue-the retina-and covers the inside of the eye like wallpaper.
 The inside of the eye is filled with a transparent, jelly-like material called the vitreous. Disorders of the vitreous body are related to the normal aging process in which the jelly begins to liquefy, resulting in a mixture of liquid and gel. Where the solid and liquid meet in the eye, debris tends to gather, resulting in "floaters" or small cobwebs that we see when we move our eyes.
When the jelly-like vitreous begins to liquefy and collapse, it may tug on the nerve-tissue lining of the eye (the retina) and produce flashes of light. This symptom should be carefully evaluated. The collapsing vitreous may be attached to the retina in spots and may cause localized tears in the retina. These tears open holes in the wallpaper-like retina; the liquid portion of the vitreous is sometimes able to seep through the hole and peel the retina away from its blood supply in the wall of the eye. This results in a retinal detachment with potentially severe loss of vision.
Floaters and flashing lights in the vision should be evaluated by an eyecare specialist to ensure that they do not represent
a dangerous condition. If abnormal holes are found in the retina and are caught early enough, a laser can normally be used
to seal them and decrease the danger of retinal detachment. If a detachment has actually started, surgery may be required
to remedy the problem.
Southwestern Eye Center has three retina specialists, Daniel Adelberg, M.D., Anthony de Beus, Ph.D., M.D., and Ingeborg Kirch, M.D. in Phoenix and 22 Arizona locations.
Macular Degeneration:
Macular degeneration is a relatively common cause for loss of central vision in individuals over the age of 45; it is rare in younger persons. In this condition, the retina (nerve tissue) in the macula (center for sharpest vision) begins to deteriorate. The rest of the retina is usually not affected. Macular degeneration is diagnosed as either dry (atrophic) or wet (exudative). The dry form is more common than wet macular degernation. The wet form of the disease usually leads to more serious vision loss.
For those with wet macular degeneration, the Food and Drug Administration has approved Visudyne®, a drug therapy for this form of the disease (also known as photodynamic therapy, PDT) and as recent as 2005, a treatment called Macugen. Macugen (pegaptanib sodium injection), is the first effective treatment that helps preserve vision for all subtypes of neovascular AMD. The neovascular "wet" form of macular degeneration is characterized by the invasion of new, poorly formed blood vessels beneath the retina. These new blood vessels are poorly formed and leak their contents into the retina and subretinal space, casuing injury to the retina and scarring. Scientists are currently studying laser treatments for dry macular degeneration as well.
Deterioration of the macula results in blurry vision when a person looks directly at an object; peripheral or side vision is unaffected. Macular degeneration developing in one eye usually indicates that the other eye is also in danger of developing the disease. Regular examinations at home with the Amsler Grid are important to detect early changes in persons prone to macular degeneration.
Patients who have macular degeneration may find performing visual tasks such as reading, writing, typing, sewing, etc. still possible with the use of magnification and strong, focused lighting.
Photodynamic Therapy (PDT)
In photodynamic therapy, a light-activated drug known s Visudyne® is injected into the bloodstream. The drug travels in the bloodstream and collects in the abnormal blood vessels, where it is activated by a non-thermal laser (a laser that does not burn the retina). This produces a reaction that closes the abnormal vessels without causing damage to the overlying retina.
Photodynamic therapy is a multi-course treatment.
The desired result cannot be achieved with just one or two treatments.
Multiple treatments are necessary because leakage often reoccurs and
the abnormal blood vessels may return after treatment. However, Visudyne®
can be reapplied at up to three month intervals, if necessary. A typical
treatment schedule for eligible AMD patients is three treatments in
the first year, two times in the second year, and one to two treatments
in the third year. Diabetic Retinopathy:
Diabetic retinopathy is a complication of diabetes that is caused by abnormal changes in the retina. The retina is a nerve layer at the back of the eye that senses light and helps to send images to your brain. In diabetes, the blood vessels in the retina may leak fluid or blood, grow fragile brush-like branches and scar tissue. This can blur or distort the images that the retina sends to the brain.
Diabetic retinopathy is the leading cause of new blindness among adults in the United States. People with untreated diabetes are said to be 25 times more at risk for blindness than the general population. Today, with improved methods of diagnosis and treatment, only a small percentage of people who develop diabetic retinopathy have serious vision problems. With careful monitoring, your ophthalmologist can begin treatment before sight is affected. Laser and operative surgery are highly effective treatments for diabetic retinopathy, but your attitude and attention to medications and diet are also essential in dealing with the disease. |
