Age-related Macular Degeneration (AMD)
Age-related macular degeneration (AMD) is a medical condition which usually affects older adults and results in a loss of vision in the center of the visual field (the macula) because of damage to the retina.
It is a major cause of blindness and visual impairment in older adults (>50 years).
Starting from the inside of the eye and going towards the back, the three main layers at the back of the eye are the retina, which contains the nerves; the choroid, which contains the blood supply; and the sclera, which is the white of the eye. The macula is the central area of the retina, which provides the most detailed central vision.
It occurs in “dry” and “wet” forms. In the dry (nonexudative) form, cellular debris called drusen accumulates between the retina and the choroid, and the retina can become detached. In the wet (exudative) form, which is more severe, blood vessels grow up from the choroid behind the retina, and the retina can also become detached. People with drusen can go on to develop advanced AMD. The risk is higher when the drusen are large and numerous and associated with disturbance in the pigmented cell layer under the macula.
- Family history
- Macular degeneration gene
- Oxidative stress
- Exposure to sunlight