Health Encyclopedia


What is glaucoma?

Glaucoma is a health problem where the normal fluid pressure inside the eyes slowly builds up and doesn’t drain properly. Instead, the fluid collects and causes damage to the optic nerve.  The optic nerve is a bundle of nerve fibers that connects the retina with the brain. This damage leads to loss of eyesight.

There are many different types of glaucoma:

  • Open-angle glaucoma
  • Low-tension or normal-tension glaucoma
  • Angle-closure glaucoma
  • Childhood glaucoma
  • Congenital glaucoma
  • Primary glaucoma
  • Secondary glaucoma

What causes glaucoma?

The causes of glaucoma are unknown. Even people with normal fluid pressure inside the eyes can lose their eyesight from glaucoma.

Who is at risk for glaucoma?

Anyone can develop glaucoma. However, some people are at higher risk than others. The risk factors for glaucoma are:

  • Race. Glaucoma is the leading cause of blindness for African-Americans.
  • Age. People ages 60 and older are more at risk for developing glaucoma.
  • Family history. People with a family history of glaucoma are more likely to develop the disease.
  • High fluid pressure inside the eyes. People with a high fluid pressure inside the eyes are at an increased risk.

Anyone in these risk groups should get an eye exam with dilated pupils every two years.

What are the symptoms of glaucoma?

Most people who have glaucoma do not notice any symptoms until they start to lose some of their eyesight. As optic nerve fibers are damaged by glaucoma, small blind spots may begin to develop. They usually happen on the side or in their peripheral vision. Many people do not notice the blind spots until significant optic nerve damage has already happened. If the entire nerve is destroyed, the person becomes blind.

One type of glaucoma, called acute angle-closure glaucoma, does produce noticeable symptoms. This is because there is a quick buildup of pressure in the eye. These are the most common symptoms of this type of glaucoma. However, each person may experience symptoms differently. Symptoms may include:

  • Blurred or narrowed field of vision
  • Severe pain in the eyes
  • Haloes or “rainbows” around lights
  • Nausea
  • Vomiting
  • Headache

The symptoms of acute angle-closure glaucoma may look other eye problems. Get medical attention right away if you notice symptoms in order to prevent blindness.

How is glaucoma diagnosed?

Your eye doctor may do the following tests to diagnose glaucoma. He or will take your complete medical history and examine your eyes. You may also have the following tests:

  • Visual acuity test. The common eye chart test measures how well you can see at various distances.
  • Pupil dilation. The pupil is widened with eye drops to allow a close-up exam of the eye’s retina.
  • Visual field. This test measures a person’s side or peripheral vision. Lost peripheral vision may mean a person has glaucoma.
  • Tonometry. This standard test determines the fluid pressure inside the eye.

How is glaucoma treated?

Your health care provider will figure out the best treatment for you based on:

  • Your age
  • Your overall health and medical history
  • How sick you are
  • How well you can handle specific medications, procedures, or therapies
  • How long the condition is expected to last
  • Your opinion or preference

The symptoms of glaucoma sometimes look like other conditions or medical problems. Always see your health care provider for a diagnosis.

While glaucoma can’t be cured, early treatment can often control it. Treatment may include:

  • Medicines. Some medicines cause the eye to produce less fluid while others lower pressure by helping fluid drain from the eye.
  • Surgery. The purpose of surgery is to create a new opening for fluid to leave the eye.
  • Laser surgery. There are several types of surgeries using a laser that are used to treat glaucoma.
  • Tube shunt. A flexible plastic tube is placed in the eye to help drain fluid.

In some cases, a single surgery isn’t enough to slow down the progress the glaucoma. In those cases repeat surgery and/or continued treatment with medicines may be necessary.

What are the complications of glaucoma?

Without treatment, glaucoma can cause permanent blindness.

Living with glaucoma

To help prevent your glaucoma from getting worse, it’s important to follow your health care provider’s advice. If you have already lost some of your eyesight, ask your health care provider for information on services for people with low vision. There are devices that may help you with your everyday tasks.

When should I call my health care provider?

If your symptoms get worse or you have new symptoms, call your health care provider.

Key points about glaucoma

  • Glaucoma is a health problem where the normal fluid pressure inside the eyes slowly builds up and doesn’t drain properly
  • Most people who have glaucoma don’t notice any symptoms until they start to lose some of their eyesight
  • Acute angle-closure glaucoma can damage your vision, cause severe eye pain, nausea, vomiting, and headache
  • While glaucoma can’t be cured, early treatment can often control it
  • Treatment may include medicines and/or surgery
  • Without treatment, glaucoma can cause permanent loss of eyesight

Next steps

Tips to help you get the most from a visit to your health care provider:
  • Before your visit, write down questions you want answered.
  • Bring someone with you to help you ask questions and remember what your provider tells you.
  • At the visit, write down the names of new medicines, treatments, or tests, and any new instructions your provider gives you.
  • If you have a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your provider if you have questions.

Medical Reviewers:

  • Berry, Judith, PhD, APRN
  • Bogus, William J., OD, FAAO