Glaucoma is a series of eye diseases that lead to damage to the nerve cells of the retina and the optic nerve in the later stages of the disease. Glaucoma is usually caused by increased intraocular pressure in the chambers of the eye. The two chambers of the eye are located in the front part of the eye near the lens and are connected by the pupil. The chambers are filled with aqueous humor, which is normally renewed by a balanced inflow and outflow. The angle of the ventricle is the area where the aqueous humor flows in and out.
If glaucoma is left untreated, over time it can lead to visual field loss and even complete blindness. By the time the affected person notices the disturbance of his vision, the optic nerve is often already severely and irreversibly damaged.
Glaucoma is one of the most common causes of blindness. In industrialized countries, about one in three cases of blindness is due to glaucoma. According to estimates, approximately three million people in Germany, for example, have elevated intraocular pressure (the main cause of glaucoma). About 800,000 of them have already developed glaucoma. Most of those affected are unaware of their condition.
The risk of developing glaucoma increases with age. About eight percent of people over 75 and up to 15 percent of people over 80 suffer from glaucoma.
Different forms of glaucoma are distinguished. These can be divided into four main groups:
- Primary open-angle glaucoma:This form ofglaucomais the result of a disturbance in the outflow of aqueous humor due to deposits (called plaque material). It is the most common type of glaucoma in older people. Normal-tension glaucoma is a chronic form of open-angle glaucoma in which the eye pressure is within the normal range.
- Angle-closure glaucoma: If the chamber angle is closed, an angle-closure glaucoma can occur. A distinction is made between acute and intermittent angle-closure glaucoma. In contrast to earlier definitions, the term glaucoma is now only used for chronic angle-closure glaucoma (in which damage to the optic nerve occurs).
- Primary congenital glaucoma:This is caused by developmental abnormalities of the angle of the ventricle, resulting in a congenital outflow obstruction of the aqueous humor.
- Secondary (acquired) glaucoma:This form of glaucoma is caused by other eye diseases that cause aqueous humor outflow obstruction. Examples of this would be complications from injuries, eye inflammation or diabetes mellitus.