Macular degeneration (patient information): Difference between revisions
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The recommended supplements contain: | The recommended supplements contain: | ||
* 500 milligrams of vitamin C | |||
* 400 International Units of beta-carotene | |||
* 80 milligrams of zinc | |||
* 2 milligrams of copper | |||
'''Wet macular degeneration'''<br> | '''Wet macular degeneration'''<br> | ||
Although there is no cure for wet AMD, treatments may include: | Although there is no cure for wet AMD, treatments may include: | ||
* Laser surgery (laser photocoagulation) -- a small beam of light destroys the abnormal blood vessels. | |||
* Photodynamic therapy -- a light activates a drug that is injected into your body to destroy leaking blood vessels. | |||
* Special medications that slow the formation of new blood vessels in the eye (anti-angiogenesis, anti-VEGF therapy) -- drugs such as bevacizumab (Avastin) and ranibizumab (Lucentis) are injected into the eye to stabilize or improve vision. This is a painless process. | |||
Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life. | Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life. | ||
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What is macular degeneration?
Macular degeneration is an eye disorder that damages the macula, which is responsible for central vision and is located near the center of the retina. The disease gradually destroys sharp, central vision, thereby making it difficult to see fine details. Because it normally affects older adults, the disorder is also called age related macular degeneration. According to the American Academy of Ophthalmology, it is the leading cause of central vision loss (blindness) in the United States today for those over the age of fifty years.[1]
Macular degeneration occurs in two forms: dry and wet.
- Dry macular degeneration occurs when the blood vessels under the macula become thin and brittle. Small yellow deposits, called drusen, form under the macula. As these drusen increase in size and number, they create a blurred and dim spot in the central vision of the eye. Almost all people with macular degeneration start with the dry form. It has three stages, all of which may occur in one of both eyes:
- Early dry macular degeneration
- Intermediate dry macular degeneration
- Advanced dry macular degeneration
- Wet macular degeneration occurs when abnormal blood vessels behind the retina start to grow under the macula. This is called choroidal neovascularization. These new blood vessels tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye, which leads to rapid damage of the macula. Although only about 10 percent of people with macular degeneration have this form, it causes most of the vision loss associated with the condition. With wet macular degeneration, loss of central vision can occur quickly, and there are no stages.
All people who have the wet form had the dry form first. Both the wet form and the advanced dry form are considered advanced macular degeneration, and vision loss occurs with either form.
What are the symptoms of macular degeneration?
At first there may not be any symptoms. However, as the disease progresses, central vision may be affected. It is very important to note that macular degeneration typically does not affect side (peripheral) vision, meaning patients will not have complete vision loss from this disease. Although specific symptoms vary by whether the form is dry or wet, both forms cause no pain.
More detailed symptoms by type include:
- Dry macular degeneration: The most common early sign is blurred vision in the center of the field of vision. As fewer cells in the macula are able to function, people will see details less clearly in front of them. Often objects in the central vision look distorted and dim, and colors look faded. Often this blurred vision will go away in brighter light. A patient may have trouble reading print or seeing other details, but can generally see well enough to walk and perform most routine activities. If the loss of these light-sensing cells becomes great, people may see a small, but growing, blind spot in the middle of their field of vision. In the later stages, patients may not be able to recognize faces until people are close to them. Dry macular degeneration generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected.
- Wet macular degeneration: The classic early symptom is that straight lines appear distorted and wavy. This results when fluid from the leaking blood vessels gathers and lifts the macula, distorting vision. A small blind spot may also appear in wet macular degeneration, resulting in loss of one's central vision. Central vision loss can occur very quickly. If this occurs, the patient urgently need evaluation by an ophthalmologist with experience in retina disease.
What are the causes of macular degeneration?
Macular degeneration is caused by damage to the area around blood vessels that supply the macula. Although scientists are not sure what causes this to happen, the change in the blood vessels is what damages the macula.
Who is at risk for macular degeneration?
The greatest risk factor is age. Although macular degeneration may occur during middle age, studies show that people over age 60 are clearly at greater risk than other age groups. For instance, a large study found that people in middle-age have about a 2% risk of getting macular degeneration, but this risk increased to nearly 30% in those over age 75.
Other risk factors include:
- Smoking: Smoking may increase the risk of macular degeneration.
- Obesity: Research studies suggest a link between obesity and the progression of early and intermediate stage macular degeneration to advanced macular degeneration.
- Race: Whites are much more likely to lose vision from macular degeneration than African Americans.
- Family history: Those with immediate family members who have macular degeneration are at a higher risk of developing the disease.
- Gender: Women appear to be at greater risk than men.
- Diet: Diets high in fat may increase the risk of macular degeneration
How to know you have macular degeneration?
If you are over age 60 and you have had changes in vision, your eye care provider will do an examination. During the exam, the doctor will use drops to enlarge (dilate) your pupils, and a special lens to view your retina and optic nerve.
The doctor will look for changes in the blood vessels and the membrane that surrounds them. This may show drusen, the yellow deposits that form on this membrane in dry macular degeneration.
You may be asked to cover one eye and look at a pattern of lines called an Amsler grid. If the straight lines appear wavy, it may be a sign of macular degeneration.
Other tests for macular degeneration may include:
When to seek urgent medical care
Treatment options
Dry macular degeneration
No treatment exists for dry macular degeneration. However, a combination of vitamins, antioxidants, and zinc may slow the progression of the disease. This combination of vitamins is often called the "AREDS" formula. Smokers should not use this treatment.
The recommended supplements contain:
- 500 milligrams of vitamin C
- 400 International Units of beta-carotene
- 80 milligrams of zinc
- 2 milligrams of copper
Wet macular degeneration
Although there is no cure for wet AMD, treatments may include:
- Laser surgery (laser photocoagulation) -- a small beam of light destroys the abnormal blood vessels.
- Photodynamic therapy -- a light activates a drug that is injected into your body to destroy leaking blood vessels.
- Special medications that slow the formation of new blood vessels in the eye (anti-angiogenesis, anti-VEGF therapy) -- drugs such as bevacizumab (Avastin) and ranibizumab (Lucentis) are injected into the eye to stabilize or improve vision. This is a painless process.
Low-vision aids (such as special lenses) and therapy can help you use the vision that you have more effectively, and improve your quality of life.
Diseases with similar symptoms
Where to find medical care for macular degeneration
Directions to Hospitals Treating macular degeneration
Prevention of macular degeneration
What to expect (Outlook/Prognosis)
Sources
http://www.nlm.nih.gov/medlineplus/ency/article/001000.htm
http://www.nei.nih.gov/health/maculardegen/armd_facts.asp
- ↑ de Jong PT (2006). "Age-related macular degeneration". N Engl J Med. 355 (14): 1474–1485. PMID 17021323.