AMD - Definition
AMD - Definition
Macular Degeneration (AMD)
For being able to see we receive the information from our environment by the eyes and piece them together in an integral picture in our brain. Thereby the retina plays a central role – the information from the nerve cells are converted into electric impulses and are directly transferred to the brain via the optic nerve.
A small area in the retinal middle is the macula – it has the biggest concentration of optic cells and it is the spot of the sharpest eyesight. Information about brightness, contrasts and colours are completed here to a sharp and coloured picture. The remaining part of retina is apprehending almost only outlines and bright-dark contrasts.
How AMD develops
The macula causes an intensive metabolism – the strongest one in the human body. Thereby waste products occur which can be accumulated on the retina. If the person is healthy, the waste products of metabolism are processed by the pigment epithelium (the tissue layer under the retina).
Formation of strangles However, the older a person gets the less is working the natural purification of the macula – the remaining rests are accumulated and they disturb the metabolism. There arise the so called “strangles” at the outer layer of the pigment epithelium which are causing brittle spots through which blood vessels can flow later. Therefore tumescence or haemorrhage in and under the macula can arise.
Disturbed metabolism Because of the disturbed metabolism the pigment epithelium produces furthermore the substance lipofuscin which causes additional damages. Environmental factors, such as UV light and free metabolic radicals, additionally support the formation of lipofuscin.
Cause of the disease The experience shows that genetic factors can play a role during the cause of the disease – with about 60 per cent of the patients the disease occurs even with members of the family. Furthermore, smokers have a threefold risk of being taken ill with AMD. However, other risk factors are even high blood pressure, circulatory diseases and lack of vitamins or minerals.
