Adult Macular Degeneration
(Age-Related Macular Degeneration, AMD)
Definition
Adult macular degeneration (AMD) is an eye disease that results in a loss in central vision that gets worse over time. The macula is the part of the retina that controls central vision. The retina is the tissue that lines the back of the eye. AMD happens when the macula wears down.
There are 2 types:
- Dry form—parts of the macula get thinner and protein deposits called drusen affect vision
- Wet form—new blood vessels grow under the macula and begin to leak blood and other fluids into the retina
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Causes
The cause is not known. It may be due to a combination of genetics and the environment.
Risk Factors
This problem is more common in adults 50 years of age and older. It is also more common in people with dark-colored eyes.
Other things that may raise the risk are:
- Prior cataract surgery
- Farsightedness
- Smoking
- Excessive exposure to sunlight
- A diet that is low in certain vitamins and minerals
- Alcohol use disorder
- Heart disease
- Obesity
- Having other family members with AMD
Symptoms
In some people, AMD slowly gets worse and has little effect on vision. In others, it moves quickly and may lead to significant vision loss. It does not cause pain.
Problems may be:
- Blurred eyesight that may go away in brighter light
- Problems seeing details in front of the eyes, such as faces or words in a book
- A small but growing blind spot in the middle of a person's field of vision
- Straight lines (such as door frames) appear crooked or distorted
Diagnosis
The doctor will ask about your symptoms and health history. A physical exam will be done. This may be enough to suspect AMD.
A doctor who treats eyes will do an eye exam and view the retina. This can confirm the diagnosis.
Some people may need images taken of the eyes. This can be done with:
- Angiography—a dye is used to make blood vessels easier to see
- Optical coherence tomography (OCT)—uses a dim red light to take a picture of the retina
Treatment
Treatment depends on the type and severity of AMD.
Dry AMD
Dry AMD cannot be treated. These things may slow the disease:
- Vitamin and mineral supplements
- Not smoking
Wet AMD
The goal of treating wet AMD is to reduce or destroy new blood vessels. Choices are:
- Laser photocoagulation to destroy new blood vessels with a strong laser light beam
- Photodynamic therapy uses a light-sensitive dye and laser light to destroy problem blood vessels
- Vascular endothelial growth factor inhibitor is a medicine that is injected in the fluid in the back of the eye to reduce the number of new blood vessels
Prevention
To lower the risk of this problem:
- Eat a healthy diet that is rich in fruits, vegetables, fish, and nuts.
- Make sure to get enough vitamins and minerals.
- Use a hat and sunglasses when outside.
- Do not smoke.
RESOURCES:
American Macular Degeneration Foundation
https://www.macular.org
Macular Degeneration Foundation
http://www.eyesight.org
CANADIAN RESOURCES:
AMD Alliance International
http://www.amdalliance.org
Canadian Association of Optometrists
https://opto.ca
REFERENCES:
Age-related macular degeneration (AMD). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/age-related-macular-degeneration-amd. Accessed October 29, 2020.
Age-related macular degeneration (AMD). National Eye Institute website. Available at: https://nei.nih.gov/health/maculardegen. Accessed October 29, 2020.
American Academy of Ophthalmology (AAO). Preferred Practice Pattern guidelines on age-related macular degeneration. AAO 2015 Jan.
Macular degeneration. Macular Degeneration Foundation website. Available at: https://eyesight.org/macular-degeneration. Accessed October 29, 2020.
What is macular degeneration? American Academy of Ophthalmology website. Available at: http://www.aao.org/eye-health/diseases/amd-macular-degeneration. Accessed October 29, 2020.
Last reviewed September 2020 by EBSCO Medical Review Board James P. Cornell, MD Last Updated: 4/30/2021