Macular degeneration, also known as AMD, is a disease that affects the retina.
The retina is a layer at the back of the eyeball, it contains light-sensitive cells and helps us see the world around us. Macular degeneration affects the patient's central vision. Images that used to be clear may start appearing blurred. Eventually, dark spots may appear. These spots typically get progressively bigger.
The majority of people with macular degeneration find that straight lines become curved or distorted, and colors are darker than they used to be, or less vivid.
People with macular degeneration gradually find it much harder to read, write, recognize faces and drive. The macula, or macula lutea (Latin: macula = spot + lutea = yellow) is an oval shaped yellow spot near the center of the retina of the eye.
Macular degeneration (AMD) mainly affects older adults.
Macular degeneration is a major cause of partial-blindness among people aged 50 plus. Although the person's central vision is affected, there is usually enough peripheral vision to allow other activities of daily life.
The macula is at the center of the retina and provides the most detailed central vision.
Some scientists found that when neurons stop getting visual input from one part of the retina, they begin responding to input from another part of the retina.
According to the National Institutes of Health "Regular comprehensive eye exams can detect macular degeneration before the disease causes vision loss. Treatment can slow vision loss. It does not restore vision."
Researchers from Johns Hopkins Bloomberg School of Public Health reported in the journal JAMA Ophthalmology that patients with loss of visual acuity due to age-related macular degeneration travel much less locally than those with vision impairment caused by glaucoma.
AMD occurs in dry and wet forms
- Dry macular degeneration - this type develops gradually. There is no treatment. There are things the patient can learn to cope with it.
- Wet macular degeneration - this type can develop more quickly. As soon as symptoms appear the patient requires treatment immediately. Wet macular degeneration is more serious than dry macular degeneration.
Who gets AMD?
Generally people over 50 years of age - this is known as age-related AMD (age-related macular degeneration). According to the NHS (National Health Service, UK), AMD affects:
- 2% of people aged 50+
- 8% of people aged 65+
- 20% of people aged 85+.
People who have a close relative with AMD have a significantly higher risk (50%) of eventually developing it compared to other people (12%). Scientists believe a new genetic association will better help predict those at risk and ultimately lead to better treatments.
Marilyn Gozdon can tell you from personal experience why it's crucial to know your risks for age-related macular degeneration (AMD).
Younger people can develop macular degeneration. However, this is very rare and is generally caused by a genetic condition. Juvenile Macular Degeneration is also known as Stargardt's disease (STGD).
Below are some more factors which may contribute to the risk of AMD:
- High blood pressure (hypertension) - people who suffer from hypertension are more at risk of developing macular degeneration.
- High cholesterol and/or obesity - a higher percentage of obese people and/or people with high blood cholesterol levels are more likely to develop macular degeneration.
- Dietary fat - studies indicate that people who consume a lot of saturated fats have a higher risk of developing macular degeneration.
- Race - studies in the USA indicate that a higher percentage of Caucasian-Americans get macular degeneration compared to African-Americans.
- Light exposure - some studies indicate that high-energy visible light may be a contributory factor. However, other studies do not. A study found that some types of AMD have been linked to low plasma levels of antioxidants and blue light exposure from the sun.
- Smoking - A regular smoker increases his/her chances of developing macular degeneration significantly - in fact, people who currently smoke have four times the risk of developing AMD, compared to lifelong non-smokers.
On the next page we look at the symptoms of AMD and how it is diagnosed. On the final page we discuss the available treatments for AMD and the possible complications.