What is glaucoma?

Glaucoma refers to a group of eye diseases that damage the nerves carrying images from the eye to the brain. Primary open angle glaucoma (POAG) is a leading cause of blindness in the United States, according to the National Eye Institute. Glaucoma usually produces no symptoms until the disease has progressed to the point of damaging a person's sight.

Glaucoma defines a group of diseases that develop due to high fluid pressure within the eye. These diseases damage the optic nerve and can lead to some or all loss of eyesight. Vision loss due to any type of glaucoma is normally a gradual process.

Robert Abel Jr
Glaucoma is a disease of wasting of the optic nerve and the retinal nerve fibers which feed it. With clogging of the drainage sites for the eye fluid, the pressure may rise. However, eye pressure alone does not make for the diagnosis of glaucoma. It is really the health of the blood supply to the back of the eye that supplies those nerve fibers carrying the image from the retinal receptors through the optic nerve to the brain. Reduced blood supply in relationship to the pressure of the fluids inside of the eye will cause a drop out in nerve fibers giving a characteristic picture of optic nerve thinning.
We have two involuntary nervous systems, the parasympathetic and the sympathetic systems. When there is a disturbance in the balance between them, that's when we experience chronic stress. The parasympathetic nervous system controls the relaxation response and slows the heart rate; the sympathetic (or adrenaline) nervous system controls the anxiety response, speeding the heart rate and breathing. In some cases each response is necessary, which is why we have dual nervous system wiring. If a mugger is chasing you down the street, you want your sympathetic (adrenaline) nervous system to go into high gear and get you out of there. After you escape to safety, however, you don't want your heart to continue pounding or to remain in a state of high anxiety. Then, your parasympathetic nervous system takes over, relaxing you, and slowing your heart rate and breathing. With sustained imbalance between these two nervous systems, diseases like glaucoma can develop. We know chronic stress is not good for health in general. That's why it's extremely important to learn how to deal with stress through rhythmic, exercise meditation or other stress busters.
While the exact reason for how glaucoma damages the optic nerve is unknown, it is clear that all types of glaucoma are due to the lack of blood flow to the retina and optic nerve.
If you are at risk for developing glaucoma, take that risk seriously. Glaucoma is the second most important cause of blindness in the United States (after diabetic retinopathy). If glaucoma is detected early and treated properly, blindness can be prevented.
Many senior adults are affected by glaucoma and do not even know it. There are usually no early warning signs and most people are unaware that anything is wrong.
Glaucoma, in most cases, is an elevated pressure inside of the eye. This increase in pressure causes damage to the optic nerve and therefore leads to vision loss.  Most of the time, the disease progresses slowly. Usually there is no pain. Sometimes in susceptible people, the pressure rises rapidly and the patient experiences sudden decreased vision and intense eye pain. In either case, loss of vision from glaucoma can usually be prevented if the disease is detected and treated early.
When glaucoma is suspected, a test can detect subtle vision loss. This test is called a visual field test. If the ophthalmologist feels that glaucoma is present, the pressure can usually be lowered with eye drops or pills. In rare cases, laser surgery or an operative procedure may be necessary to lower the pressure and preserve the sight.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)

Glaucoma is a group of diseases that can damage the eye's optic nerve resulting in vision loss and blindness. It occurs when the normal fluid pressure inside the eye rises. Risk factors include African American descent, near-sightedness, and a family history.

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Glaucoma is one of the leading causes of blindness in the United States. It is a disease of the optic nerve, which is the part of the eye that carries the images we see from the eye to the brain. Glaucoma can damage nerve fibers, causing blind spots in our vision.

High eye pressure or intraocular pressure (IO P) can put you at risk for developing glaucoma. Aqueous humor is a clear liquid that normally flows in and out of the eye. When this liquid cannot drain properly, pressure builds up in the eye. The resulting increase in IOP can damage the optic nerve.

The most important risk factors for glaucoma include:

  • Age
  • Elevated eye pressure
  • Family history of glaucoma
  • African or Latino ancestry
  • Past eye injuries

The only sure way to detect glaucoma is with a complete eye examination. Symptoms of glaucoma are not noticeable until damage has already occurred. Early diagnosis and treatment are the keys to preventing blindness.

Your ophthalmologist can determine if you have glaucoma after examining the pressure in your eye, your optic nerve and your peripheral (side) vision.

Glaucoma is usually controlled with eyedrops. Laser surgery or operative surgery may be done if the drops do not control the disease. These treatments only stop further damage; they cannot reverse any damage or loss of sight that has already occurred. That is why early detection and taking eyedrops as prescribed are so important to prevent blindness from glaucoma.

Audrey K. Chun, MD
Geriatric Medicine
Glaucoma is a disease in which the optic nerve is damaged, usually due to high pressures within the eye. The nerve damage can result in a slowly progressive loss of vision, beginning with peripheral vision. Diagnosing glaucoma before there is vision loss is critical, since there is no way to restore the vision lost due to glaucoma.
Michael T. Murray, ND
Naturopathic Medicine

Glaucoma refers to increased pressure within the eye (intraocular), which results from greater production than outflow of the fluid of the eye (the aqueous humor). The normal intraocular pressure (IOP) is about 10 to 21 mm Hg. In chronic glaucoma, the IOP is usually mildly to moderately elevated, at 22 to 40 mm Hg. In acute glaucoma, the IOP is greater than 40 mm Hg.

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Glaucoma is a progressive loss of vision from damage to the optic nerve, a set of nerves that runs from the retina (the membrane at the back of the eyeball) to the brain. The damage usually occurs because the watery fluid of the eyeball (the aqueous humor) does not circulate properly through various parts of the eye, and the fluid (and pressure) builds up in the eyeball. Eventually, this high intraocular pressure (IOP) kills cells and nerve fibers and can lead to blindness.

Glaucoma is a serious eye condition, in which pressure is high within the eye. It can cause permanent vision loss. There are two types of glaucoma. One occurs suddenly, and if it is not treated within hours it will cause permanent vision loss. The other type occurs slowly over the years, and the patient may not realize that vision is slowly being lost.
Glaucoma is a fluid pressure build-up in the eye that damages the optic nerve. It is a leading cause of blindness.

Chronic glaucoma often goes unnoticed in the early stages, when peripheral vision may be affected. Once diagnosed, chronic glaucoma can usually be treated with eye drops. Sudden-onset, or congenital, glaucoma may require surgery.
Glaucoma is a group of eye diseases in which the normal pressure inside the eye rises slowly and becomes too high for the retina and optic nerve to function properly. People of African descent have greater risk for vision loss from glaucoma. Initially, there are no symptoms and vision stays normal. As the disease progresses, however, peripheral vision gradually starts to fail and people feel like they are looking through a tunnel. Over time, the entire vision can be impaired.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.