However, vision already lost to glaucoma cannot be restored. That is why the American Optometric Association recommends an annual dilated eye examination for people at risk for glaucoma.
Depending on your specific condition, your doctor may recommend more frequent examinations. There are many theories about the causes of glaucoma, but the exact cause is unknown. Although the disease is usually associated with an increase in fluid pressure inside the eye, other theories include a lack of adequate blood supply to the nerve.
This is the most common form of glaucoma. Damage to the optic nerve is slow and painless. Those affected can lose a large portion of vision before they notice any vision problems.
One theory about its development is that the eye's drainage system becomes inefficient over time. This leads to an increased amount of fluid and a gradual buildup of pressure within the eye. Another theory about the cause of this type of glaucoma is that there is poor blood flow perfusion to the optic nerve. Other theories also exist. This type of glaucoma, also called closed-angle glaucoma or narrow-angle glaucoma, is a less common form of the disease.
It is a medical emergency that can cause vision loss within a day of its onset. It occurs when the drainage angle in the eye formed by the cornea and the iris closes or becomes blocked. Many people who develop this type of glaucoma have a very narrow drainage angle.
With age, the lens in the eye becomes larger, pushing the iris forward and narrowing the space between the iris and the cornea.
As this angle narrows, the fluid in the eye is blocked from the drainage system. Therefore the fluid builds up and eye pressure increases. Angle-closure glaucoma can be chronic progressing gradually or acute appearing suddenly.
The acute form occurs when the iris completely blocks fluid drainage. When people with a narrow drainage angle have their pupils dilated, the angle may close and cause a sudden increase in eye pressure. Although an acute attack often affects only one eye, the other eye may be at risk of an attack as well. This type of glaucoma results from an injury or another eye disease. It may be caused by a variety of medical conditions, medications, physical injuries, and eye abnormalities.
Infrequently, eye surgery can lead to secondary glaucoma. In this form of glaucoma, eye pressure remains within the "normal" range, but the optic nerve is damaged nevertheless. It is not known why this happens. Possibly, people with low-tension glaucoma have an abnormally sensitive optic nerve.
Or they may have a reduced blood supply to the optic nerve caused by a condition such as atherosclerosis, a hardening of the arteries. Under these circumstances, even normal pressure on the optic nerve can cause damage. The signs or symptoms of glaucoma can vary depending on the type.
Primary open-angle glaucoma often develops slowly and painlessly, with no early warning signs. It can gradually destroy one's vision without even knowing it. The first indication that a person has glaucoma may occur after some vision has been lost.
Acute angle-closure glaucoma results from a sudden blockage of drainage channels in the eye, causing a rapid buildup of pressure. In this form of the disease, a patient would have blurred vision, the appearance of halos or colored rings around lights, and pain and redness in the eye. Glaucoma is diagnosed through a comprehensive eye examination.
Because glaucoma is a progressive disease, meaning it worsens over time, a change in the appearance of the optic nerve, a loss of nerve tissue, and a corresponding loss of vision confirm the diagnosis. Some optic nerves may resemble nerves with glaucoma, but the patients may have no other risk factors or signs of glaucoma.
These patients should have routine comprehensive exams to monitor any changes. Glaucoma treatment is aimed at reducing pressure in the eye. Regular use of prescription eye drops are the most common and often the first treatment. Some cases may require systemic medications, laser treatment, or other surgery. While there is not yet a cure for glaucoma, early diagnosis and continuing treatment can preserve eyesight. A number of medications are currently available to treat glaucoma.
Typically, medications reduce elevated pressure in the eye. A single medication or a combination of medications may be prescribed. The type of medication may change if it is not reducing pressure enough or if the patient is experiencing side effects. Procedures include laser treatment, making a drainage flap in the eye, inserting a drainage valve, or destroying the tissue that creates the fluid in the eye.
All procedures aim to reduce the pressure inside the eye when medication is not sufficient. Surgery cannot reverse vision loss. Laser trabeculoplasty helps fluid drain out of the eye. A high-energy laser beam stimulates the structure that drains fluid from the eye the trabecular meshwork so that fluid drains more efficiently.
Yes No. Watch this video for tips and advice from glaucoma specialist Terri Pickering, MD. Read more ». Where the Money Goes. More information ». Like Us on Facebook. We appreciate support from corporations who believe in our mission to educate glaucoma patients and speed a cure.
Order Now. Text Size. Contrast Dark on Light Light on Dark. What is Glaucoma? In This Section. Glaucoma Facts and Stats. Related Media Video: What is Glaucoma? If you have glaucoma, early diagnosis and treatment can help stop your vision getting worse. Without treatment, glaucoma can eventually lead to blindness. The most common is called primary open angle glaucoma.
This tends to develop slowly over many years. It's caused by the drainage channels in the eye becoming gradually clogged over time. Most cases are caused by a build-up of pressure in the eye when fluid is unable to drain properly. This increase in pressure then damages the nerve that connects the eye to the brain optic nerve.
It's often unclear why this happens, although certain things can increase the risk, including:. It's not clear whether you can do anything to prevent glaucoma, but having regular eye tests should pick it up as early as possible.
Glaucoma can usually be detected during a routine eye test at an opticians, often before it causes any noticeable symptoms. Find out if you're eligible for free NHS eye tests. Several quick and painless tests can be carried out to check for glaucoma, including vision tests and measurements of the pressure inside your eye.
If tests suggest you have glaucoma, you should be referred to a specialist eye doctor ophthalmologist to discuss treatment. Find out how glaucoma is diagnosed.
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