Center for Sight

Comprehensive Eye Care Center

Age Related Macular Degeneration (AMD)

Macular Degeneration or Age Related Macular Degeneration (AMD) is a common senior eye problem that is an incurable eye disease. It is the leading cause of legal blindness for those aged 55 and older in the United States, affecting more than 10 million Americans in some fashion. The Macula is responsible for providing central vision which is the sharpest or clearest area of your vision and is required for activities such as seeing fine detail of faces, reading and recognizing colors. The Macula provides you with the precise vision required for driving a car and is responsible for central or “straight ahead” vision. Your chances of developing Age Related Macular Degeneration (AMD) are directly related to your age. The older you are, the greater the chance that Macular Degeneration will affect you.

Age Related Macular Degeneration (AMD) is a degenerative condition of the Macula that is caused by hardening of the small arteries supplying oxygen and nutrients to the Retina. The hardening and narrowing of these arteries deprives the Macula of oxygen and nutrition. This results in a slow but progressive loss of function. The visual effects of Macular Degeneration can be relatively minimal with a mild “dimming” or “distortion” of your central vision, or very profound resulting in a complete loss of your central vision. However, Macular Degeneration DOES NOT result in total blindness. Since the effect of Macular Degeneration is limited to the central retina, its effects are limited to central vision and thus it does not cause any loss of your peripheral vision.
There are two main types of Age Related Macular Degeneration (AMD): “Dry Macular Degeneration” and “Wet Macular Degeneration”

Dry Macular Degeneration
Dry Macular Degeneration, also called Atrophic Macular Degeneration, is the most common type of Age Related Macular Degeneration, making up some 85-90% of cases. Dry Macular Degeneration results in a slow, gradual progressive “dimming” of your central vision. If you have Dry Macular Degeneration, during your eye exam the doctor will see small, yellow colored deposits between the retinal layers, which are called drusen. Many people 50 years of age or older begin to display some drusen as they age and are not a direct problem for your vision unless they are large or confluent. If you have drusen, your doctor may ask you to schedule eye exams more frequently or order additional testing such as Optical Coherence Tomography (OCT) or Intravenous Fluorescein Angiography (IVF) in order to monitor them, as there is some possibility that Dry Macular Degeneration will progress to Wet Macular Degeneration over a period of time. Thus people with Dry Macular Degeneration, even without any noticeable change in vision, need to be followed closely as Wet Macular Degeneration has far more serious consequences for vision loss.

Wet Macular Degeneration
Wet Macular Degeneration is far more likely to cause serious vision loss than Dry Macular Degeneration but fortunately only accounts for about 10-15% of cases. Wet Macular Degeneration is characterized by an abnormal growth of new blood vessel under the retina called “neovascularization” that is fragile and prone to be leaky and can easily break and bleed. If leakage occurs, the Macula may actually begin to swell. If the new blood vessels break and bleeding occurs, it can result in scarring as it heals. Scarring of the Macula can cause a sudden, rapid and severe loss of central vision, which is irreversible.