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Macular Degeneration

Human  cross-sectional view. Courtesy  . Many animals have eyes different from the human eye.

Macular degeneration is a medical condition where the light sensing cells in the macula malfunction and over time cease to work. It is the main cause of central vision loss in the USA blindness today for those over the age of fifty (Am.Acad.Ophthalmol.). There are two basic types of the disease: Standard Macular Degeneration (MD) and Age Related Macular Degeneration (ARMD). The main cause of macular degeneration is old age and thus age related macular degeneration is the most common form of the condition. However macular degeneration that is not age related is most commonly caused by disease or a heredity illness or condition. These forms are sometimes called Juvenile macular degeneration. In macular degeneration the final form results in complete blindness in the central part of the patient's vision.

Types of Degeneration

Eighty five to ninety percent of all macular degeneration is categorized as "dry" macular degeneration where fatty tissue will slowly build up behind the retina. Ten to fifteen percent of cases are not, however, resulting from the build up of fatty tissue; these cases are called "wet" macular degeneration due to the leakage of blood and other fluid from behind the retina into the eye. If wet macular degeneration continues without treatment it will completely destroy the macula. Medical, photodynamic, laser photocoagulation and laser treatment of wet macular degeneration are available. The success of treatment and vision preservation is facilitated by early detection( This is contemplated by home monitoring by the patients using a grid pattern called Amsler Grid test (Home Amsler Color Test ( The test that is a black and white pattern to be viewed misses majority of defects ( references at ) caused by the progression and therefore a more sensitive blue on yellow test pattern has recently been introduced.

Typical Symptoms

  • A grid of straight lines appears wavy and parts of the grid appear blank.
  • Visual acuity drastically decreasing (two levels or more) ex: 20/20 to 20/80.
  • Holes visible in fundus photographs.
  • Trouble discerning colors; specifically dark ones from dark ones and light ones from light ones.

Illnesses and Conditions that Cause Macular Degeneration

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