What causes macular degeneration of the eyes?

The Macula is an area in the retina, which is responsible to our central vision.  It is the most active area of our eyes.  The Macula is the only area in our eyes that possesses both the rods and cones photoreceptors. Patients suffering from macular degeneration usually present with a loss of pigment epithelial cells as well as a change in the capillaries underneath the pigment epithelium. The pigment epithelium is similar to the film of a camera.  When it starts to deteriorate, the quality of our central vision starts to diminish.  In more advance cases of macular degeneration,  “ghost blood vessels” develop from the neighboring capillaries.  These ghost blood vessels are extremely fragile, they frequently lead to hemorrhages (leaking of blood cells and serum) or edema (leaking of serum only). This is what doctors describe as  wet form of macular degeneration.

Macular degeneration is a complex disease, and can be caused by multiple factors.  It arises either from ischemic changes, from exposure to toxic substance including UV or high energy radiation, or as a result of genetically transmitted diseases. For a video description of macular degeneration, click here. 


Is age related macular degeneration an autoimmune disease?

Macular degeneration is a complex disease, its cause is unclear but it is likely due to a combination of oxidative damage, arteriosclerotic changes at the macula, and genetic predisposition.  The finding from National Eye Institute concluded that antioxidant vitamins and minerals slow disease progression supports the idea that it is likely due to oxidative damage such as UV light and smoking.  So far no evidence is found to support the connection between Macular Degeneration and autoimmune disorders.


Is macular degeneration a genetic condition?

Macular degeneration occurs in a much higher rates within families and in twins than in the general population.  Some studies even suggested the likelihood of developing age related macular degeneration is 50% amount siblings.  The national genome project suggested that people who are homozygous for the 402H complement factor H polymorphism have up to 7 times increased risk of developing age related macular degeneration.


How to prevent macular degeneration?

Since macular degeneration is related to arteriosclerotic changes as well as oxidative damages.  We recommend all patients with family history of macular degeneration to practice certain precaution:

  1.         If you are a smoker, stop smoking.

  2.         Eat a balance diet rich in fruits and vegetables, the antioxidant in                                             most of the vegetable and fruits can counteract the oxidative damages caused by free radicals.

  3.         Reduce cardiovascular risk factors, including lowering cholesterol and saturated fact intake and controlling hypertension.


How can we help patient with macular degeneration?

Macular degeneration is a atrophic condition, therefore, whatever damages occurred is not reversible.  However, we can control or slow down the progression of the condition.  The first approach should be the lifestyle changes like what we mentioned above.  Secondly, we recommend the intake of micronutrient supplement such as vitamins A,C, and E as well as Lutein and Zeaxanthin.  Lately, there is evidents that essential fatty acid is also helpful in controlling macular degeneration. For more advance case of macular degeneration, a cancer treatment medication call Avastin can be injected into the jelly body of the eye called Vitreous to stop hemorrhages as well as edema.  Although it is still waiting for FDA’s approval, clinical data indicated that it is a very effective treatment.  Other medication such as Visudyne, Lucentis and Macugen are also approved by FDA in the treatment of macular degeneration.

 

Macular Degeneration