Age Related Macular Degeneration (ARMD or AMD) is one of the leading cause of vision loss in elderly people. It is a disease that gradually deteriorates the central vision as ARMD resulted due to degeneration of the macula, which is the mostimportant part of the retina that is responsible for sharp central vision and appreciating fine detail. This can result in a slow, sudden painless lost of central vision.
ARMD can develop in two forms: Wet (neovascular) and Dry (non-neovascular). Neo vascular is a term given to new form blood vessels that is not supposed to be there. These blood vessels are usually not stable and can beak easily. The dry form of ARMD is more commonly seen (85 – 90%) compare to the wet form of ARMD which usually leads to more seriousvision loss.
What is Dry ARMD?
Dry ARMD is usually seen in the very early stage of the disease. This may be the result of aging and thinning of the macular tissues, depositing of pigment in the macula or a combination of the above mention process.
This result when the light sensitive cells in the macular slowly loss it function and causing gradual blurred central vision. Asit worsen, a more noticeable blurred central vision result and over time, as the macula function gets more affected, centralvision is lost in the affected eye.
The most common symptom of dry ARMD are:
- Slightly blurred vision.
- Difficulty recognizing faces.
- Required more light for daily tasks.
Dry ARMD usually affects both eyes but the vision of one eye may be lost while the other eye appears unaffected.
This condition can be diagnosed by examine the retina by optometrist or ophthalmologist using an ophthalmoscope, whichis an equipment that is being use to look at the retina.
When yellowish spots known as drusen, which are deposits or debris from deteriorating tissue, are found to accumulate inthe area of the macula, it is a sign of dry ARMD. In early dry ARMD, there will be drusen form and usually there will be no symptom or loss of central vision. However, as the disease progress, the amount of drusen increase, lost of central visionmay occur.
What is Wet ARMD?
About 10% of the cases of dry ARMD cross over to become wet ARMD, which is a more damaging form of the eye disease.When this occurs, there will be new blood vessels form (neo-vascularization) beneath the retina. As these blood vessel are not strong and stable, the can leak blood and fluid causing permanent damage to the light sensitive retinal cells whicheventually die off and create a blind spot in the central vision.
Wet ARMD are classified into 2 general types:
1. Classic; When neovascularization result in the retinal and cause scarring which has very clear delineated outlinesobserved beneath the retina. This is know as choroidal neovascularization (CNV) and is usually associated with moresevere vision loss.
2. Occult; When neovascularization occurs beneath the retina which does not cause a significant leakage of blood and fluid.This is a less serious CNV condition and will have less severe vision loss.
An amsler grid is a chart of black lines arranged in a graph pattern is one way to diagnose whether a person is having vision problem related to ARMD.
An optometrist or ophthalmologist often detects early signs of macular degeneration before a person develop symptoms.This can only be achieved by a retinal examination using either an ophthalmoscope or a retinal photography.
If a person is suspect of having macular degeneration, a brief test using the Amsler grid is perform. This measure your central vision and allows the eye care practitioners to detect any defect to your central vision such as distortion orblurriness. The result of the amsler grid test may appear like the picture shown below if the macular is affected.
Cause and Risk Factors of Macular Degeneration
The most common and highest risk of Macular Degeneration is aging. Although ARMD can occur during middle age, studieshas been conducted to show that a person, age about 60, have a higher chances of have this disease compare to other age group (Feb17 2004 edition of Canadian Medical Association Journal)
Other risk factors are:
Smoking is a major risk factor of developing macular degeneration according to a clinical studies. It is directly associated with about 25% of macular degeneration cases resulting in lost of vision. In early 2006, it is published in the British JournalOf Ophthalmology that study showing that a person living with a smoker double the risk of macular degenerationdeveloping.
Recent clinical research shows that specific variants of two different genes are present in most people who have maculardegeneration. Those with immediate family members who have ARMD are at a greater risk of developing this disease.
Studies have shown that overweight patients with macular degeneration have more than double the risk of developing advanced forms of the disease compare to normal body weight. It is also found that those who does vigorous activity atleast three times a week have a reduce risk of developing advance ARMD compare to those inactive people.
Female appears to have a greater risk compare to male.
Whites are much more likely to develop severe vision loss due to ARMD as compare to African Americans.
How Macular Degeneration can be treated?
There is no cure for macular degeneration yet. However, there are some treatments which may delay its progression oreven to improve the vision. Treatment that is given depends on the stage of the disease.
According to Age Related Eye Disease Study (AREDS) by the National Eye Institute’s, they found that taking high dosage ofspecific antioxidants and zinc significantly reduces the risk of advanced ARMD and it associated vision loss.
Many researcher and eyecare practitioners believe that certain nutrients such as zinc, luteing, zeaxanthin and vitamin A, C and E helps to lower the risk of developing ARMD or even to slow down the progression of the disease. Benefits of using high level of antioxidant and zinc to reduce the risk of developing or progression of ARMD has been widely reported basedon the results that was released in 2001 AREDS reports.
The specific daily intake amount of antioxidant and zinc according to AREDS were 500 mg of vitamin C, 400 internationalunits of vitamin E, 15 mg of beta carotene, 80 mg of zinc as zinc oxide and 2 mg of copper as cupric oxide.
For wet ARMD, laser may be one treatment for the condition to seal up the leakage to prevent the condition from gettingworse.
ARMD is a condition that can cause painless central vision loss and it affects the elderly people mostly. It does not have anypain or early visual disturbing symptoms. Therefore, it is important to have a regular eye examination by optometrist or ophthalmologist, to have a retina examination in order to make sure that macular degeneration and other eye disease is not present.
Nutrition should be taken with care and consultation with your physician before consuming any nutrition is recommended.
References & Pictures:
- Complete Guide to Macular Degeneration; www.allaboutvision.com/conditions/amd.htm
- Related Macular Degeneration (NEI Health Information); www.nei.nih.gov/health/maculardegen/armd_facts.asp
- Macular Degeneration; http://www.stlukeseye.com/Conditions/MacularDegeneration.as