Glaucoma

Glaucoma is an eye disease in which the internal pressure of the eye rises to a point where the optic nerve becomes damaged. The pressure that builds up is from an excessive production of the fluid in the eye (aqueous humour) that for one reason or another, does not drain properly.

Glaucoma is an important cause of blindness. In many countries, 2% of people over 40 years of age have glaucoma and in South Africa, glaucoma is common and very serious. It accounts for 20 % of blindness.

This is far more common than acute glaucoma in most countries and mostly affects the middle-aged and elderly.

There is a strong hereditary factor; therefore relatives of people with glaucoma should be screened.

This is an uncommon type of glaucoma in South Africa. It affects the middle-aged and elderly, especially women. People who are long-sighted have a greater risk of developing the disease than those who are short-sighted.

This form is rare and occurs at birth or in the first few years of life.

The high pressure is secondary to some other eye disease such as untreated cataract, an eye injury or inflammation in the eyeball.

Chronic glaucoma is, unlike acute glaucoma, a very silent disease with no pain or early symptoms to warn the patient. There is gradual, progressive loss of vision and peripheral (side vision) first and, because the patients straight ahead vision and reading vision remains good initially, many people are unaware that their eyesight is deteriorating until the disease is advanced. With progression, tunnel vision can develop and lead to difficulty with reading and other activities and eventually the eye can become totally blind if untreated.

Acute glaucoma usually starts with a sudden attack of painful red eyes and blurred eyesight, often with headaches, nausea and vomiting. The symptoms are often severe enough to cause the patient to seek emergency treatment although some unfortunately wait longer, resulting in greater permanent damage to the eyes. Some patients have milder temporary attacks of pain and blurring of vision before they get a severe prolonged attack

The aim of all forms of treatment is to lower the eyeball pressure and prevent further damage to the optic nerve.

Treatment depends on the type of glaucoma and may be by medicine (eye drops or tablets), surgery, or by laser.

Acute glaucoma requires surgery or laser treatment to control the pressure. Eye drops and tablets are used as supplementary treatment.

Chronic glaucoma can often be treated by medication alone but if this is found to be insufficient, laser treatment or surgery is recommended.

1. Glaucoma almost always affects both eyes, although not always simultaneously. Therefore, once high pressure has been detected in one eye treatment should be considered for both eyes.
2. Early diagnosis and treatment is desired because once the optic nerve is damaged, the loss of vision is permanent.
3. When a definite diagnosis of glaucoma has been made patient should be followed-up regularly by an eye specialist for life, even if the eyeball pressure is controlled by medication or surgery. A normal pressure after treatment implies that the disease is controlled rather than cured.

Glaucoma is a common cause of blindness which can be prevented by early detection and proper treatment.

Consult an eye specialist immediately if you develop painful red eyes with blurred vision.

Have your eyeball pressure checked regularly after the age 40; especially if you have a relative who has glaucoma.