Ophthalmology
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Macular Degeneration (DMAE)

As we age, the macula (the small part of the retina at the back of the eye that provides sharpness of vision) begins to break down and produces small white particles called drusen, which are seen in a fundus photograph and in a cross-sectional diagram above. These can be an early sign of macular degeneration, but they do not usually cause vision loss by themselves and not all patients who develop drusen go on to develop macular degeneration.

The dry or atrophic form of age-related macular degeneration, seen above in fundus photography and in a cross-sectional diagram, is the most common form of macular degeneration, accounting for about 90 percent of cases. Although this form of macular degeneration does not usually cause severe vision loss, it can progress to the wet form, so patients who have it should see their ophthalmologist regularly.

The wet or exudative form of macular degeneration , seen here in fundus photography and in a cross-sectional diagram, affects about 10 percent of macular degeneration patients. Wet macular degeneration is caused by the growth of abnormal blood vessels at the back of the eye that can leak fluid and blood. wet macular degeneration typically causes significant vision problems in the affected eye and can progress very rapidly and cause permanent vision loss.

What is macular degeneration?
The eye is often compared to a camera. The front of the eye contains a lens that focuses images on the back of the eye. This area, called the retina, is covered with special nerve cells that react to light, like film in a camera.
These nerve cells are very close together in the middle of the retina where the eye focuses the images that we see. This part of the retina is called the macula.

What is age-related macular degeneration?
There are two types of age-related macular degeneration - the dry (atrophic) form and the wet (exudative) form. The dry form of macular degeneration affects about 90 percent of patients and usually begins with the formation of tiny yellow deposits called drusen in the macula. Drusen usually do not cause serious loss of vision, but can cause distortion of vision. However, for reasons that are not yet understood, sometimes drusen will cause the macula to thin and break down, slowly leading to vision loss.

Wet macular degeneration occurs in about 10 percent of age-related macular degeneration patients. It is caused by the growth of abnormal blood vessels beneath the macula that can leak fluid and blood.

The wet form of macular degeneration typically causes significant vision problems in the affected eye and can progress very rapidly, causing permanent central vision loss.

The exact cause of age-related macular degeneration is not known. Age-related macular degeneration may be hereditary. If someone in your family has or has had macular degeneration, you may be at higher risk for developing the disease.

Both of these conditions are called age-related macular degeneration. If there are no new blood vessels being created, it is "dry" macular degeneration. When new blood vessels start to grow, it is called "wet" macular degeneration.

Why do people get macular degeneration?
The exact cause of macular degeneration has not been found. Things like smoking, exposure to direct sunlight over a period of years, a lack of vitamin A and some medical conditions seem to make people more likely to get macular degeneration.

Some people also seem to inherit a tendency to have macular degeneration. None of these things can really be said to cause macular degeneration, however, and there is no sure way to prevent the condition.

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