What is Age-Related Macular Degeneration?

Age-related macular degeneration (AMD) is the most common cause of blindness later in life in the developed world.

While this disease is not fully understood, research by this and other groups is bringing us closer to a complete knowledge of the mechanism of this debilitating disease.

The macula is a small region of the light-sensitive retina at the back of the eye responsible for our detailed vision (for example, watching television, reading, using computers, driving and recognising faces) and also for colour vision. Hence it could be said that it is the most important part of the retina.

Are there different kinds of AMD?

There are two types of AMD, the early form, and the late form.

AMD starts with the dry from and about ten percent of people will go on to develop the wet form.

Early macular degeneration

• This is the first stage of macular degeneration
• There is no definite treatment for early macular degeneration, although increasing macular pigment levels seems to have some beneficial effects
• It is caused when drusen, deposits of lipofuscin form at the macula
• It tends to develop slowly, causing some deterioration in central vision, blurry vision, and seeing objects in a distorted manner

Late macular degeneration

We can subdivide late AMD into two categories - late dry or geographic atrophy and late wet or CNV (choroidal neovascularisation).

• About ten per cent of people with the early form of macular degeneration will go on to develop the late form.
• Geographic Atrophy is called thus because it has a discrete demarcated area around the macula which does not correspond to any physical structures.
• CNV is the formation of new fragile blood vessels in the choroid the layer below the retina underneath the macula. These delicate blood vessels can leak or bleed causing a rapid damaging affect on vision.