What is glaucoma?

Diana Meeks
Diana Meeks on behalf of Sigma Nursing
Family Practitioner

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.

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 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.

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.

Dr. Jeanne Morrison, PhD
Family Practitioner
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.

Continue Learning about Glaucoma

Can Blindness Be Prevented?
Can Blindness Be Prevented?
What Are the Challenges in Treating Glaucoma?
What Are the Challenges in Treating Glaucoma?
How Has Glaucoma Treatment Advanced?
How Has Glaucoma Treatment Advanced?
Do genetics Play a Role in Eye Diseases Like Glaucoma?
Do genetics Play a Role in Eye Diseases Like Glaucoma?

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.