The macula contains a very high density of light receptors, especially the light cone receptors. Light-cone receptors are receptors that detect color. So that the macula is very important to see fine detail and objects directly in front of the eye.
Macula plays an important role in helping people to read, write, drive and perform other detailed tasks. The macula also allows people to be able to recognize faces and see the color.
Age Related Macular Degeneration, the Blind Maker
There are two types of AMD, namely:1. Dry AMD
Is the most common form of the condition. Light receptor cells in the retina to function less well with age. The cells did not take adequate nutrition is important and becomes less efficient in functioning.
This causes tiny abnormal deposits, called drusen, which are under the retina. As time went on retinal cells degenerate and die, causing loss of vision.
This happens gradually over many years. Dry AMD has three stages, namely:
a. Early AMD: small to medium-sized drusen, without symptoms or without vision loss.
b. Intermediate AMD: early symptoms such as blurred vision in the center, and need a brighter light when reading.
c. Advanced AMD: destruction more widespread than the light-sensitive cells and deteriorating eyesight.
2. Wet AMD
Wet AMD experienced a number of 10 to 15 percent of AMD cases. Wet AMD is also known as neovascular AMD since it involves the growth of new blood vessels behind the retina.
New blood vessels are very fragile it may be leaking fluid or blood, raised, and distorts the retina. This causes distortion of vision and scarring that causes rapid vision loss.
Any person who has a condition that leads to the development of wet AMD have dry AMD first. Wet AMD can progress very rapidly and is difficult to predict.
Cause
It is unclear what causes AMD, but AMD may be caused by a combination of genetic susceptibility to environmental factors. People with a family history have an increased risk, because it can carry the same gene.
AMD becomes more likely in older people, because AMD develops from time to time. Other diseases can exacerbate the disease process of AMD and cause damage to cells in the macula.
Symptom
Symptoms that may occur in AMD, among others:
1. Usually about two eyes, although one eye may be affected first.
Good eye usually compensates for the eye that had been exposed for years. So that it can disguise the fact that there is a problem in sight.
2. There is no pain or redness in the eye.
3. Affect central vision.
This is because the macula is located in the middle. So that people can only see from the edge of the eye only. The focus and sharpness of color in the edge region is very less.
4. Any activity that requires a detailed vision and obviously very disturbed.
5. In the final stage which has been severe, patients can suffer blindness.
Treatment
Currently, there are no medical treatments that have proven reliable for treating dry AMD. However, some things that can minimize the severity of AMD, among others:
1. Not smoking and eating a healthy diet can help to slow the rate of damage.
Dietary supplements on a regular basis, such as vitamin C, vitamen E, and zinc can help to slow vision loss for some people who already didignosa AMD. Two nutrients known as carotenoids lutein and zeaxanthin, in some cases seem to be able to reduce the progression of AMD.
2. Additional lighting can help people with dry AMD to be able to optimize the use of their remaining vision.
When AMD develops, treatment is recommended as soon as possible. Treatment of wet AMD in many cases, can prevent further deterioration of vision, and in some cases bring about some improvement of vision. Treatment of wet AMD is aiming to control the formation of new blood vessels that leak.
There are three types of treatment for wet AMD, among others:
1. Photocoagulation
The method uses a hot laser to seal leaking blood vessels, but can only be used in a minority of cases where leakage is not directly in the center of the macula.
These include destructive methods of treatment that can damage the surrounding healthy tissue and new blood vessels often grow back afterward, thus requiring repeated treatment.
2. Photodynamic therapy (PDT)
Using light-based treatment to seal leaking blood vessels. This method involves injecting a drug called verteporfin is circulating in the bloodstream and line the inside of the abnormal blood vessels.
This method does not damage the surrounding tissue but repeated treatments may be needed.
3. Therapy with VEGF inhibitors
In recent years new treatments have been developed aimed to disrupt the destructive process of development of new blood vessels (neo-angiogenesis) which is the focus of treatment for wet AMD.
Some drugs target proteins involved in the process, called vascular endothelial growth factor or VEGF. High levels of VEGF can cause proliferation of blood vessels and fluid leakage.
The drugs, known as VEGF inhibitors or anti-VEGF, needs to be injected into the eye, precisely under the macula, the number of injections varies. Although the experimental injections given either every 4 or 6 weeks, in practice, physicians must decide the most appropriate treatment based on assessment of patient response to medications.
Therapy with VEGF inhibitors have been aimed at stopping the loss of vision and in some cases to restore vision.
Sources: BBCHealth
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