Macular degeneration is an eye disease that is very common in the elderly. In developed countries it is a frequent cause of vision deterioration. To understand the nature of the disease, it is appropriate to know some basic information about the anatomy of the eye and the macula.
The light comes into the eye through the cornea and then it passes through the lens onto the ocular the retina. The retina consists of many light-sensitive cells (retinal rods and cones) that capture the light energy and convert it into neural impulses. This neural information is transmitted via the optic nerve into the brain vision center. The brain processes the information as the visual perception. The density of sensory cells in the retina is not uniform. In one area there is a large amount of cones and this place is referred to as the "yellow spot" or macula lutea. This area guarantees the best and sharpest color vision.
Macular degeneration is caused by disorders of small blood vessels in the retina that are affected by the atherosclerosis, high blood pressure, high cholesterol, oxidative stress and smoking. Some forms of the macular degeneration occur in young age as a consequence of genetic predispositions. Damage of the retinal blood vessels affects the macula and causes death of its sensory cells. Damaged vessels may be replaced by new ones but these are usually fragile and allow leakage of blood fluid and blood proteins into local the retina. These small retinal hemorrhages can permanently damage the macula.
Macular degeneration manifests with slow deterioration of the center of our visual field usually in form of a dark or dime patch. The problem worsens and can result in a complete loss of vision. Perception of colors deteriorates as well and the colors appear faded.
When the above mentioned problems occur, it is necessary to perform a basic eye examination including the eye fundus exam and evaluation of peripheral vision. The peripheral vision should stay more or less normal in macular degeneration.
Smoking cessation is necessary. It is important to properly treat the high blood pressure, dyslipidemia and prevent the oxidative stress (sufficient vitamin intake). Bleeding of newly formed retinal blood vessels can be treated by a laser. Relatively promising is the use of biological treatment that consists of with the administration of drugs blocking the formation of new blood vessels in the retina.