Macular Degeneration
Introduction:
As we age so does the part of our retina that has been the most active in terms of central vision, the fovea or macula. For some reason, possibly due to genetic predisposition, the macula undergoes an age-related degeneration easier in whites than in blacks, particularly in old age. That's why this condition is also called "senile macular degeneration". There are two forms how this degeneration can occur, a dry form and a wet form. With the common dry form there is an atrophic process happening in the macula, but there are no hemorrhages or exudates. With the wet form of macular degeneration, which is more rare, a neovascularization (new blood vessels) process is happening in the choroidal membrane of the retina where the pigment cells are located.
This leads to bleeding into the retina, leakage of fluid (called exudate) underneath the retina and a threat of retinal detachment.
Signs and symptoms:
There is a visual loss without pain in both eyes with the characteristic findings as indicated under the links "dry form" and "wet form" above.
In the beginning of this degenerative process there might be a visual problem on only one eye, which shows up as distortion on the Amsler's chart. This is a squared grid of lines, which is viewed at a distance of 35 cm (=12 inches) from the eyes. When there is a distortion of the grid, it is time to see an eye specialist on an urgent basis. There might be pigmentary lesions and drusen that alarm the eye physician that macular degeneration is imminent.
Diagnostic tests:
Fluorescein angiograms can be used to study the absence or presence of a neovascular membrane formation underneath the retina. It is with the experience of the eye specialist, the fluorescein angiograms, the visual tests, slit lamp, direct and indirect ophthalmoscopy tests that the diagnosis of macular degeneration is made.
Treatment:
If there is a neovascular network identified by fluorescein angiograms, the eye specialist may decide to do laser photocoagulation in order to attempt to stop further deterioration. Although the central vision will often be lost, there is still peripheral vision outside of the macula in the remainder of the retina. In other words, patients do not lose all of their sight. However, they will need support services of one or more of these support services, which you can find under this link
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