What is Glaucoma?

Glaucoma is an eye disease that involves damage to the optic nerve, the part of the eye that carries the images we see to the brain. The optic nerve is like an electric cable containing about 1.2 million wires. This condition can damage nerve fibers, causing blind spots to develop. In the most common type of Glaucoma, patients may experience a gradual narrowing of their peripheral vision that creates “tunnel vision.”

Glaucoma is a leading cause of blindness in the United States, especially for older people, but loss of sight can often be prevented with early treatment.

What causes Glaucoma?

Increased pressure inside the eye can be the culprit. Pressure builds up in the eye when the clear liquid called the aqueous humor, which normally flows in and out of the eye, is prevented from draining properly. This can happen in different ways, depending on the type of Glaucoma. The resulting increase in pressure within the eye can damage the optic nerve. As the optic nerve deteriorates, blind spots develop in the visual field. This can develop in one or both eyes.

Eye doctors used to think that high intraocular pressure was the main cause of optic nerve damage. Today, however, we know that even people with “normal” pressure can experience vision loss from Glaucoma. On the other hand, some people with high intraocular pressure never develop optic nerve damage. (These people need to be followed carefully by an eye doctor, because they are considered “Glaucoma suspects.”)

Symptoms of Glaucoma

Common Symptoms:

By the time your vision is damaged from Glaucoma, the disease has been at work for a long time. There are some signs and symptoms that may be noticeable before Glaucoma reaches an advanced stage, including:

  • Sensitivity to light and glare
  • Trouble differentiating between varying shades of light and dark
  • Trouble with night vision, halos around lights
  • Loss of side vision
  • Eye pain or discomfort

Risk Factors:

Anyone can develop glaucoma. Some people are at higher risk than others. They include:

  • Over the age of 40
  • Family history of glaucoma
  • Abnormally high eye pressure
  • African, Scandinavian, Celtic or Russian ancestry
  • Diabetes
  • Nearsightedness
  • Regular, long-term use of steroids/cortisone
  • Previous eye injury

Early detection of Glaucoma is the best way to control the disease. If you fall into one of the higher risk groups, it is very important to have a comprehensive dilated eye exam yearly. If eye pressure can be lowered in the early stages, it can slow the progression and help prevent loss of sight.

How is Glaucoma treated?

As a rule, damage caused by Glaucoma cannot be reversed. Glaucoma is usually controlled with eye drops taken daily to decrease eye pressure. Depending upon your situation, laser surgery and surgery in the operating room are used to help prevent additional damage. Oral medications may also be prescribed.

To learn more: Facts about Glaucoma from the National Eye Institute