• Alternative names
• Defination
• Causes, Incidence and Risk Factors

• Prevention
• Symptoms
• Signs & Tests
• Treatment

• Expectations
• Complications
• Calling Your health care provider

Defination

Glaucome begins when a blockage at the front of the eye prevents the aqueous humor, the clear fluid that flows through the eye's front chamber, from exiting the eye. The result is a build-up of pressure that ultimately damages the delicate fibers of the optic nerve, which connects the eye with the brain

There are two basic forms of glaucoma, open- and closed-angle. In open-angle glaucoma, the "angle" of the anterior chamber, where the cornea meets the iris at the front of the eye, appears to be open. This allows the aqueous humor to flow through the sieve-like trabecular meshwork, which filters debris from the fluid. Deep within this tissue, however, an abnormality impedes the fluid flow out of the eye. The form of the disease known as primary open-angle glaucoma (POAG) is what most people think of as "glaucoma." Glaucoma is primary if the cause is not known and not obviously related to another eye disease. If glaucoma is caused by some other known problem, it is secondary.

POAG is characterized by elevated intraocular pressure (IOP), optic nerve damage, and visual field defects. The patient may experience blurred vision or a gradual vision loss, and the disease usually travels a chronic, insidious course over many years. Symptoms may not be evident until the later stages, making POAG the most difficult form of glaucoma to diagnose.

In closed-angle glaucoma, an anatomical abnormality pushes the iris forward, blocking both the angle and access of the fluid to the filtering tissue.

Symptoms

Glaucoma is a leading cause of blindness in part because it has no symptoms in early stages to alert the patient to the disease. As the disease advances, there is blurred vision or a gradual loss of peripheral (side) vision -- by this point, although treatment can control the disease, the lost vision cannot be restored.

Signs & Tests

Early stage glaucoma can be detected with a simple, painless test. The ophthalmologist measures the patient's IOP level with a special device called a tonometer. Changes in the optic nerve are examined with an ophthalmoscope that enables the physician to look through the pupil to see the back of the eye. Treatment begins if there is noticeable damage to the optic nerve, or if the opthalmologist feels the patient's IOP is high enough to pose a threat to the optic nerve.

Treatment

Glaucoma treatment can involve three stages. The first step is drug therapy, which often is an effective way of lowering the IOP and thus controlling the disease. If this does not work, laser treatment may be tried to open channels for fluid to escape. Laser therapy is relatively painless and is usually performed in the physician's office in two sessions over the course of a month. Some patients may require additional laser treatments or a third form of treatment, filtration surgery. During this procedure, the physician surgically creates a valve in the wall of the eye using existing eye tissue, allowing the aqueous humor to drain. This therapy, combined with close follow-up, can halt the progression of glaucoma. Until there is a cure for glaucoma, the best weapon against this potentially blinding disease is early detection, leading to a well-planned course of treatment.

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