Macular Degeneration

Macular degeneration is a group of diseases characterized by a breakdown of the macula. The macula is the center portion of the retina that makes central vision and visual acuity possible.

Age related macular degeneration (AMD) is a retinal degenerative disease that causes progressive loss of central vision. The risk of developing macular degeneration increases with age. The disease most often affects people in their sixties and seventies. Macular degenerationis the most common cause of vision loss in individuals over the age of fifty-five.

There are two types of macular degeneration: dry and wet. Dry macular degeneration accounts for about 90 percent of all cases. Dry macular degeneration is sometimes called atrophic, nonexudative, or drusenoid macular degeneration. With dry macular degeneration, yellow-white deposits called drusen accumulate in the retinal pigment epithelium (RPE) tissue beneath the macula. Drusen deposits are composed of waste products from photoreceptor cells.

Wet macular degeneration accounts for about 10 percent of cases. In wet macular degeneration, abnormal blood vessel growth forms beneath the macula. These vessels leak blood and fluid into the macula damaging photoreceptor cells. Wet macular degeneration tends to progress rapidly and can cause severe damage to central vision.

In some cases, if wet macular degeneration is diagnosed early, laser surgery can prevent extensive central vision loss. In this type of surgery, laser beams destroy the leaky blood vessels that form beneath the macula. For laser surgery to be effective, it is critical that macular degeneration be diagnosed before extensive vision loss occurs. If you are diagnosed with wet macular degeneration, you may want to ask your doctor about these treatments.

Signs of Macular Degenereation

Central vision loss from macular degeneration occurs when photoreceptor cells in the macula degenerate. The macula is the central portion of the retina responsible for perceiving fine visual detail. Light sensing cells in the macula, known as photoreceptors, convert light into electrical impulses and then transfer these impulses to the brain via the optic nerve.

Individuals with macular degeneration may first notice a blurring of central vision that is most apparent when performing visually detailed tasks such as reading and sewing. As the disease progresses, blind spots form within central vision. In most cases, if one eye has macular degeneration, the other eye will also develop the disease. The extent of central vision loss varies according to the type of macular degeneration.

Treatment

For information on current treatments for macular degeneration, click here.

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