What is glaucoma?
Glaucoma is an eye disorder where the major nerve of the eye, the optic nerve, suffers damage and may cause permanent blindness if untreated or treated inappropriately.
Glaucoma is a silent disease. The patient suffers no symptoms at the initial stages of the disease, and so does not have his eyes checked. However, in the later stages of the disease, he may consult a doctor complaining of blurred vision or eye pain. Glaucoma is the second most common cause of blindness after cataracts, and in Thailand occurs in about 1.7-2.4 per one million people.
Causes of glaucoma
1. The most important risk factor for glaucoma is increased high pressure of fluid in the eyeball, caused aqueous fluid. Normally the fluid pressure in and around the eyeball is balanced. But in patients with glaucoma, abnormality of the eye itself causes aqueous fluid within the eyeball to accumulate, building up intraocular pressure.
2. Abnormal vision, such as extreme short-sightedness.
3. Diabetes mellitus, high blood pressure
4. Congenital glaucoma (occurring since birth).
5. May occur secondary to other diseases of the eyes, like eye infections, inappropriately treated cataracts or trauma.
An eye specialist (ophthalmologist) can detect those who he suspects may develop or who may be suffering from glaucoma using different tests.
Treatment of glaucoma
Glaucoma can be controlled by maintaining normal intraocular pressures. Any nerve damage and visual loss which is found at the time of diagnosis cannot be reversed, however prevention of further nerve damage and visual loss is possible. Treatment may involve the use of eye drops, oral medications or surgery.
Surgery is most appropriate for close-angle glaucoma or those whose disease is not improved by medical treatment. There are two general types of glaucoma surgery: laser surgery and microsurgery.
After numbing the eye, a laser beam is used to open the drainage channel so allow aqueous fluid (fluid in the eye) to flow out. Laser surgery is only a temporary solution to decrease the intraocular pressure, and is usually followed by conventional surgery. Between laser and conventional surgery, eye drops must be used continually.
Microsurgery to open the drainage channel of the eye is used to treat all types of glaucoma. Local or general anaesthesia is used. It is usually performed on an out-patient basis. After surgery, the patient's eye is covered, and the patient will be instructed not to wet the eye or strain the eye by reading for one week. He or she should not bend his head down or perform any strenuous activities.