DRY OR ATROPHIC Macular Degeneration

The hallmark of late onset Macular Degeneration is the presence of drusen, mentioned earlier, that occur beneath the macular retina. After a while, having this drusen under the macula may cause the macula to thin and degenerate/atrophy thus referring to it as atrophic Macular Degeneration. This can cause a slow and progressive loss of vision in the central seeing area. Atrophic Macular Degeneration is more common than the wet form and occurs in about 9 out of 10 persons with macular degeneration. Over time the atrophy or damaged area can cause a large central blind spot also called a scatoma where there is a loss of detailed vision. This scatoma, usually an irregular shape, is found however in the very center of the retina. The damage done by dry Macular Degeneration is usually not as severe as that of the wet form or exudative form. Because the dry form can sometimes change into the wet form it is important for persons with the dry form to continue recommended ophthalmological visits and watch for new changes in vision, for instance, by using the Amsler grid. 
 

WET OR EXUDATIVE Macular Degeneration

In about 10% of cases of Macular Degeneration the eye develops new blood vessels which grow up from the choroid. These new blood vessels can leak fluid or blood which in turn can cause more damage than the degenerative process itself. This is what is known as the wet or exudative type of Macular Degeneration. You may also see terms of a doctor's report such as subretinal neovascularization which means new vessels growing underneath the retina. Keep this term is mind as you read new research reports to try to understand which type of Macular Degeneration is being studied. The wet form then, which is characterized by subretinal neovascularization can be even more severe than the dry form and occurs in about 1 in 10 of persons with Macular Degeneration. Abnormal blood vessel growth which may leak fluid, blood, or lift up the retina causes more damage the longer it occurs and goes untreated. In cases where the damage is not in the center seeing area directly, laser treatment may be done to stop or minimize loss of vision. Also, attempts to curtail the growth of these new vessels are continuing to occur in research studies to see if there are any types of drugs which may halt this progress. If the abnormal blood vessel growth occurs in one eye there is approximately a 10% chance per year that they will occur in the other eye. New studies are being done to see if a beneficial effect of radiation therapy can be done on this "wet type" of Macular Degeneration. Comparisons of data with the natural history of wet Macular Degeneration suggest a beneficial effect of radiation therapy. To date, no negative side effects have been observed. More studies are being done at this time. 
 
 

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