What is causes glaucoma
Medicated eye drops must be used exactly as prescribed otherwise their use could worsen optic nerve damage. If eye drops by themselves do not lower intraocular pressure to the desired level you may be prescribed an oral medication, usually a carbonic anhydrase inhibitor, to reduce your eye pressure. Treatment of glaucoma may require surgery if medications do not work or are not well tolerated. Surgeries to treat glaucoma include:.
The following lifestyle changes may help if you have elevated intraocular pressure or glaucoma:. Medical Library Topics. Home Medical library Glaucoma Southern Cross Medical Library The purpose of the Southern Cross Medical Library is to provide information of a general nature to help you better understand certain medical conditions.
Sight Loss Services Freephone: Email: info sightloss-services. References Akpek, E. Overview of age-related ocular conditions.
Akpek, E. Current treatment strategies for age-related ocular conditions. Mayo Clinic Glaucoma Web Page. Wellington: New Zealand Ministry of Health. Glaucoma New Zealand. It causes irreversible vision loss due to damage to the optic nerve. The loss of sight is usually gradual and a considerable amount of peripheral side vision may be lost before there is an awareness of any problem.
Unfortunately there is no cure for glaucoma, and vision loss is irreversible. Glaucoma is usually caused by an increase in intraocular pressure IOP which can damage the optic nerve.
The level of elevated eye pressure which causes progressive damage to the optic nerve varies between people. Some people can have high eye pressure without glaucoma known as ocular hypertension while other people can have normal eye pressure with glaucoma known as normal tension glaucoma.
The eye is constantly producing a clear liquid called aqueous humor which it secretes into itself. This fluid nourishes the eye and holds the eye in shape.
The fluid is then drained out though an area called the anterior chamber angle or drainage angle. If there is damage to the drainage angle, the rate at which the eye produces the aqueous humor then becomes greater than the rate the eye can drain it — causing high IOP in the eye. This increased pressure begins to damage the optic nerve which lies at the back of the eye.
The optic nerve is made up of approximately one million nerve fibres which connect the back of the eye to the brain. Damage to the cells of the optic nerve results in irreversible damage to your eyesight.
If you or a loved one has been diagnosed with glaucoma you might be feeling overwhelmed. We're here to help. While anyone may develop glaucoma, some people are at a higher risk including those with a family history of the disease and anyone over the age of Any disruption of this outflow of aqueous — including from certain eye injuries — can result in an increase in IOP.
Anatomically, the eye's drainage angle is referred to as being either "open" or "closed" narrow. The narrower the angle, the more difficult it is for the aqueous to flow through it.
An open angle also can hinder the outflow of aqueous, if structural damage exists within the ocular tissues of the angle itself. While high IOP often is associated with glaucoma, this eye disease also can occur when internal eye pressure is normal normal-tension glaucoma. People with this condition have highly pressure-sensitive optic nerves that are susceptible to irreversible damage from what ordinarily would be considered "normal" IOP.
Conversely, certain people with elevated intraocular pressure known as ocular hypertension may never develop glaucoma. Most conventional methods of screening for glaucoma involve testing eyes for the presence of high IOP. But because glaucoma can occur even without high IOP, direct examination of the optic nerve and visual field testing are essential in making or ruling out the diagnosis of glaucoma.
Though the exact cause of normal-tension glaucoma is unknown, many researchers believe decreased blood flow to the optic nerve may be a factor. This could be caused by narrowing of blood vessels that nourish the optic nerve or constrictions of these vessels vasospasms. Some studies also indicate that poor blood flow within the eye is associated with blind spots scotomas that develop within the visual field, similar to those that occur in glaucoma.