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Macular Degeneration

Macular Degeneration
Macular Degeneration
Causes and Risk Factors

Macular degeneration
Central vision is crucial to see objects clearly and accomplish tasks such as reading and driving. Macular degeneration is a disease that destroys sharp, central vision and age-related macular degeneration (AMD) is one of the leading causes of vision loss and legal blindness for Americans aged 60 and older. But what is AMD, what causes the degeneration of vision, and what risk factors contribute to the development of vision loss?

What is macular degeneration?
Macular degeneration affects the macula, the part of the eye that facilitates fine detail vision. The macula is the most sensitive part of the retina and is made up of millions of light-sensing cells that provide sharp, detailed central vision. If the macula becomes damaged, fine points in electrical images sent to the brain from the retina are not clear. The picture is there, but the fine points are lost.

What is age related macular degeneration, or AMD?
There are several forms of macular degeneration, but the fastest growing form is age-related macular degeneration (AMD). Although age related macular degeneration does not hurt or cause pain, the condition progressively causes cells in the macula to die over time. In some cases, age related macular degeneration advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. There are two forms of age-related macular degeneration -- dry and wet.

Types of age related macular degeneration

  1. Dry AMD - occurs when light-sensitive cells in the macula slowly break down, gradually blurring central vision in the affected eye. Over time, central vision slowly worsens as less of the macula functions. The dry type of age related macular degeneration occurs in 90% of all cases. Dry AMD generally affects both eyes, but vision can be lost in one eye while the other eye seems unaffected. Dry AMD occurs in three stages, all of which may occur in one or both eyes:

    Early AMD - no symptoms and no vision loss
    Intermediate AMD - more light may be needed for reading and other tasks
    Advanced Dry AMD - breakdown of light-sensitive cells and supporting tissue in the central retinal area occurs
  2. Wet or advanced AMD - occurs when abnormal blood vessels start to grow under the macula behind the retina. These new blood vessels tend to be very fragile, leak blood / fluid, and raise the macula from its normal place at the back of the eye. Damage to the macula occurs rapidly. During wet AMD, loss of central vision can occur quickly and does not occur in stages like dry AMD.

Some people are more at risk than others of developing macular degeneration.  But what causes this progressive disease?  And are you at risk for developing it?  Read on to learn more about the cause of macular degeneration.

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