What does it mean when rings shine

Colored rings are warning signs

Glaucoma, the “green star”, is the most common cause of blindness in industrialized countries. You can protect yourself from this relatively well - if the disease is recognized in good time.

The earliest sign of glaucoma is increased pressure in the eye. The eyeball is filled with a clear liquid called aqueous humor. A kind of drain valve, the chamber angle, regulates the pressure in the healthy eye. If the drain is blocked or too much aqueous humor is produced, the internal pressure can rise. This damages the optic nerve: the field of vision gradually narrows - to the point of complete blindness. Then the fundus of the eye reflects the light of the examination lamp green, which is what gave the disease its name.

It is insidious that the patient does not notice anything at first. Increased intraocular pressure does not hurt and does not yet cause visual disturbances. Chronic headaches occurring later in the morning, eye pain or seeing colored rings around bright light sources are also not associated with glaucoma. That is why glaucoma sufferers often only see a doctor when the first damage to the optic nerve is there. They cannot be reversed.

The ophthalmologist can determine increased intraocular pressure with the applanation tonometer. To do this, a small pen with a pressure sensor is placed on the eyeball. The normal value for intraocular pressure is 17 millimeters of mercury on the measuring device, values ​​over 20 are already considered to be elevated.

The risk of glaucoma increases with age: Every tenth person over 40 has increased intraocular pressure. Doctors and health insurance companies therefore recommend regular checks. Particularly at risk are diabetics, nearsighted people and people whose families have already had glaucoma.

Recognized in good time, the disease can be delayed with drugs that promote the outflow of aqueous humor or reduce its production. The active ingredients are usually administered as tablets. The further the glaucoma has progressed, the higher they have to be dosed so that they reach the eye in sufficient concentration. The list of unpleasant side effects on the heart, liver, psyche and immune system is two full pages in a handbook of pharmacology. Pregnant and breastfeeding women should not take any pills to lower intraocular pressure.

An alternative are lower-dose eye drops that only work locally, but are also not free from side effects. However, these occur less often and are accepted by most patients for fear of going blind.

Contrary to popular belief, lasers and scalpels are rarely used in glaucoma and only in the case of serious illnesses. A new drainage channel for the aqueous humor is cut with the knife - whether made of steel or light.

MEDINFO MEDIA

Wolfgang Leydhecker The eye counselor for diseases of the eyes from A-Z Trias, Stuttgart 1996 DM 32, -

Matthias Sachsenweger The Green and the Gray Star Ullstein, Frankfurt / M. 1994 DM 16.90

Glaucoma surgery in detail Conventional interventions, laser surgery, cold application Enke, Stuttgart 1994 DM 72.00

Franz Grehn The Glaucoma Kohlhammer, Stuttgart 1993 DM 179, -

MEDINFO CONTACT

The Initiativkreis Glaucoma Early Detection e.V. Postfach 1340 D-40638 Meerbusch, Germany Telephone 02132 - 767 80 Fax 02132 - 773 17, sends detailed information material about the green star

Helmut L. Karcher

June 1, 1997

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