The front part of the eye is filled with a clear fluid that nourishes the lens, iris and cornea. The fluid is produced constantly every hour by ciliary tissues around the lens. The fluid flows out of the inner part of the eye through the pupil and then is absorbed into the bloodstream through a meshwork of little drainage canals, all around the outer edge of the iris. The production, flow and drainage of the fluid is an active, continious process that is necessary for the health of the eye. This fluid is different from tears, wich is produced outside the eye. The internal pressure of the eye ( intraocular pressure ) depends on the amount of fluid in the eye.          
What is glaucoma?
Glaucoma is an eyedisease where the fluid in the eye does not flow normally. As a result, the pressure inside the eye rises and damages the sight. If the pressure remains high, it can cause blindness. The early visual changes are very slight and do not affect the central vision - the center portion of what is seen when looking straight ahead or reading. Certain parts of the peripheral vision - the top, sides and bottom areas of vision - are affected first. Glaucoma usually occurs in both eyes, but extra fluid pressure often begins to build up first in only one eye. It occurs in people of all ages, from children to older adults, but it is more likely to develop in people who are over 35 years old, very near-sighted, or diabetic.

The tendency to develop glaucoma may be inherited, as relatives of glaucoma patients are more likely to develop glaucoma themselves.
Vision lost as a result of glaucoma usually cannot be recovered, but early diagnosis and careful, lifelong treatment can help prevent further visual damage. Ophthalmologists recommend a glaucoma check as part of a regular eye examination.

Risk factors
Acute glaucoma is rare and strike suddenly and painfully. Chronic glaucoma is more common and creeps up on a person without him knowing it and slowly robs him of his eyesight.

  1. Intraocular pressure: Elevated intraocular pressure is considered the most important risk factor. However, glaucoma may occur even with normal readings.
  2. Blood supply: Even in cases of normal intraocular pressures, a disturbed vascular regulation of the vessels supplying blood to the optic nerve head in the eye can result in glaucoma. People with low blood pressure or general circulatory disturbances are particulary at risk.
  3. A family affliction: If there is a history of glaucoma in the family, regular examinations are necessary at all ages, not just from the age of 40 onwards.
  4. Medication: Glaucoma is significantly increased by taking medicines that contain cortisone or similar active constituents.