Age-Related Macular Degeneration (AMD)
Definition | Symptoms | Treatment | Research | Clinic Information
Definition
Age-Related Macular Degeneration (AMD) is a degenerative eye disease that causes damage to the macula (central retina) of the eye. AMD is the leading cause of vision loss in our senior population. Macular Degeneration impairs central vision. People who are affected by Age-Related Macular Degeneration have problems reading, driving and performing activities that require clear central vision. There are two stages of Macular Degeneration; the more common Dry Stage and the Wet Stage.
Macular degeneration causes damage to the macula of the eye. The macula is the central part of the retina at the back of the eye that allows us to see fine details clearly. Macular degeneration makes close work like threading a needle or reading a book difficult or impossible. When the macula does not function correctly, we experience blurriness or darkness in the center of our vision. Although macular degeneration reduces vision in the central part of the retina, it does not affect peripheral vision. For example, you could see a clock but not be able to tell what time it is. Macular degeneration alone does not result in total blindness. Most people continue to have some useful vision and are able to live independently.
There are two stages of macular degeneration:
- The Dry Stage. This is the more common form. In this type of macular degeneration, the delicate tissues of the macula become thinned and slowly lose function.
- The Wet Stage. This is less common, but is typically more damaging. The wet type of macular degeneration is caused by the growth of abnormal blood vessels behind the macula. The abnormal blood vessels tend to hemorrhage or leak, resulting in the formation of scar tissue if left untreated. In some instances, the dry stage of macular degeneration can turn into the wet stage.
Macular degeneration develops differently in each person. Because it will affect regions of the macula differently from person to person, the symptoms tend to vary. Macular degeneration causes a progressive loss of central sight, however, it does not cause total blindness. Peripheral vision is unaffected, allowing a certain amount of mobility in normal surroundings. If left untreated, the wet type of macular degeneration may progress rapidly.
- Blurry vision
- Distorted vision
- Straight lines appear wavy
- Objects may appear as the wrong shape or size
- The loss of clear, correct colors
- Difficulty reading
- A dark, empty area in the center of vision
Treatment
Currently, there is no known cure for macular degeneration. There are, however, new therapies emerging.
For individuals with macular degeneration, it is highly recommended that a regular schedule of eye examinations be maintained. During these examinations, detailed documentation with photographs and fluorescein angiography may be performed. With this information, your eye doctor is better able to monitor the condition, note any changes that may occur, and determine the most appropriate therapy.
Treatment for Dry Macular Degeneration
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Supplementation with specific anti-oxidant vitamins and minerals has been shown to significantly slow the progression of Dry AMD. For details on the dosage and side-effects, please see your ophthalmologist.
Treatment for Wet Macular Degeneration
- The newest treatment for wet AMD is Lucentis, a drug that was approved by the FDA in 2006. This drug inhibits the growth and leakage of abnormal blood vessels and it is the first treatment that has been shown to improve vision in some eyes rather than simply slowing the rate of vision loss. Lucentis is delivered through tiny injections in the eye, once a month for three months, with additional, less frequent injections, as needed, for one year or more. A similar drug, Avastin, is also commonly used for the treatment of wet AMD.
Other treatments include laser treatments and photodynamic therapy. These treatments are designed to seal the leaking blood vessels, halting the damage they can inflict upon the retina. These treatments are effective in slowing the progression of wet macular degeneration and are sometimes used in combination with Lucentis or Avastin. Research is underway to find new and more effective treatments for this condition.
Research
For information on AMD research, visit Clinical Trials and the AMD Genetic Research Study.
Clinic Information
For more information, see the Retina, Uveitis & Ocular Oncology Clinic or the Center for Retinal and Macular Degeneration at the U-M Kellogg Eye Center.
