Age-related Macular Degeneration
Age-related macular degeneration is the most common cause of severe vision loss in Americans over the age of 65. Macular degeneration can affect the central or reading vision but usually does not affect peripheral vision. Macular degeneration does not cause complete blindness and most persons with macular degeneration retain enough vision to be able to care for themselves and walk around without assistance. The symptoms of macular degeneration include often include blurred, dim, or distorted vision. Some persons note a black spot in front of their central vision. Central vision is essential to allow people to read and drive so macular degeneration may be first recognized by difficulty reading or difficulty reading road signs while driving. Most macular degeneration has a gradual onset and many patients don't realize they are losing vision. The symptoms usually develop first in one eye so unfortunately the symptoms of macular degeneration are often missed until a person covers the unaffected eye. Loss of central vision in one or both eyes should result in a prompt visit to your eye doctor.
Types of macular degeneration
The cause of macular degeneration is not very well understood but it is known that it relates to aging in specific layers of the retina. There are two forms of macular degeneration which are called atrophic ("dry") and exudative ("wet"). Both forms can cause decreased vision but the wet type usually causes more severe and more rapid visual loss. Most persons diagnosed with dry macular degeneration will continue to have dry macular degeneration although dry macular degeneration may evolve into wet macular degeneration.
Treatment
There is a large research effort being devoted to try to improve treatment of dry and wet macular degeneration since it is becoming a greater public health problem as life expectancy increases. There are few treatments for dry macular degeneration but a study called the Age Related Eye Disease Study (AREDS) found that certain anti-oxidants (vitamin A, C and E) and minerals (zinc and copper) helps to slow the progression of dry macular degeneration once it reaches an intermediate stage.
Wet macular degeneration is typically treated today with a class of drugs called anti-VEGF (anti-vascular endothelial growth factor) which are administered into the eye. These drugs include ranibizumab (Lucentis®), or bevacizumab (Avastin®), and the recently FDA approved, Eylea, VEGF-trap medication. These drugs help shrink abnormal blood vessels in wet macular degeneration and result in improved vision or prevent further loss of vision.. Laser treatment can be very useful in eyes where the source of the leakage is outside of the center of vision. All of the existing therapies for wet macular degeneration appear to work best if they are performed earlier in the course of the disease, when leakage is localized. Hence, early detection is the most important goal to preserve vision from macular degeneration. Increased public awareness about the symptoms of macular degeneration will help to prevent unnecessary visual loss from this disease.
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