Glaucoma
Glaucoma is a disease that causes damage to the optic nerve. Partial loss of vision or even blindness will occur if left untreated. Glaucoma can occur at any age, most people who develop glaucoma are usually in their mid 60s.
The risk of developing glaucoma increases if there are persons in the family that have glaucoma.
What causes glaucoma?
The most common type of glaucoma is chronic simple (opened angle) glaucoma, which often causes no symptoms until loss of vision is advanced. It is due to gradual blockage of the outflow of aqueous humour (fluid in the front compartment of the eye) over a period of years, causing a slow rise in pressure. This type tends to run in family.
Acute (Closed angle) glaucoma occurs when there is a sudden obstruction to the outflow of aqueous humour from the eye and the pressure rises suddenly.
Congenital glaucoma is caused by structural abnormality of the drainage angles of the eyes.
Glaucoma can also be caused by injury to the eye, eye diseases and long term usage of certain drugs.
Signs and symptoms
Chronic simple glaucoma is usually painless and vision loss changes are difficult to detect in early stages. Only late in the disease, when there is severe, irreversible damage, may be person be aware of some visual loss.
The symptoms of acute glaucoma include dull, severe, aching pain in and above the eye, some blurred vision and the perception of halos at night. Nausea and vomiting may occur and the eye may become red and have partly dilated pupil and hazy cornea.
Diagnosis
Detection of chronic simple glaucoma is usually discovered during a routine eye examination as it usually causes no symptoms. Tonometry measuring the pressure in the eye, visual field test, used to test the integrity of peripheral vision and ophthalmoscopy, to view the state of the optic disc, will help to determine the possibility of glaucoma
Increasingly, HRT is being used by ophthalmologists to detect and diagnose glaucoma years before any symptoms become apparent to the patients. HRT is especially useful at detecting small changes over time and to monitor the persons who are at risk of developing glaucoma.
Treatment
Special eye drops or even medication by mouth can be used to help lower the pressure within the eye.
Laser surgery also be used. Narrow angle glaucoma can be treated with laser iridotomy. Chronic simple glaucoma can also be treated with laser trabeculoplasty.
Trabeculectomy is used to treat glaucoma that can not be adequately controlled with medications or laser surgery. This operation creates a small channel in the eye to prevent build up of excess pressure caused by aqueous humour. |
