Macular degeneration is a deterioration or breakdown of the macula. The macula is a small area in the retina at the back of the eye that allows you to see fine details clearly and perform activities such as reading and driving. When the macula does not function correctly, your central vision can be affected by blurriness, dark areas or distortion. Macular degeneration affects your ability to see near and far, and can make some activities - like threading a needle or reading - difficult or impossible.
Although macular degeneration reduces vision in the central part of the retina, it does not affect the eye's side, or peripheral, vision. For example, you could see the outline of a clock but not be able to tell what time it is. Macular degeneration alone does not result in total blindness. Even in more advanced cases, people continue to have some useful vision and are often able to take care of themselves. In many cases, macular degeneration's impact on your vision can be minimal.
What Causes Macular Degeneration?
Many older people develop macular degeneration as part of the body’s natural aging process. There are different kinds of macular problems, but the most common is age-related macular degeneration (AMD). Exactly why it develops is not known, and no treatment has been uniformly effective. Macular degeneration is the leading cause of severe vision loss in caucasians over 65.
The two most common types of AMD are “dry” (atrophic) and “wet” (exudative):
“Dry” Macular Degeneration (Atrophic)
Most people have the “dry” form of AMD. It is caused by aging and thinning of the tissues of the macula. Vision loss is usually gradual.
“Wet” Macular Degeneration (Exudative)
The “wet” form of macular degeneration accounts for about 10% of all AMD cases. It results when abnormal blood vessels form underneath the retina at the back of the eye. These new blood vessels leak fluid or blood and blur central vision. Vision loss may be rapid and severe.
Macular degeneration can cause different symptoms in different people. The condition may be hardly noticeable in its early stages. Sometimes only one eye loses vision while the other eye continues to see well for many years. But when both eyes are affected, the loss of central vision may be noticed more quickly. Following are some common ways vision loss is detected:
- Words on a page look blurred
- A dark or empty area appears in the center of vision
- Straight lines look distorted
Fluorescein and Indocyanine Green Angiography, as well as Optical Coherence Tomography(OCT) are performed in the office to diagnose bleeding blood vessels under the retina. Intravitreal Lucentis, Macugen, Avastin and steroid injections as well as photodynamic therapy can be used for treatment.