What is Glaucoma?

Glaucoma is a group of eye conditions that damage the optic nerve, the health of which is vital for good vision. This damage is often caused by abnormally high pressure in your eye.

Glaucoma is one of the leading causes of blindness for people over the age of 60. It can occur at any age but is more common in older adults.

Many forms of glaucoma have no warning signs. The effect is so gradual that you may not notice a change in vision until the condition is at an advanced stage.

Because vision loss due to glaucoma can't be recovered, it's important to have regular eye exams that include measurements of your eye pressure so a diagnosis can be made in its early stages and treated appropriately. If glaucoma is recognized early, vision loss can be slowed or prevented. If you have the condition, you'll generally need treatment for the rest of your life.
Symptoms

The signs and symptoms of glaucoma vary depending on the type and stage of your condition. For example:

Open-angle glaucoma

Patchy blind spots in your side (peripheral) or central vision, frequently in both eyes
Tunnel vision in the advanced stages
Acute angle-closure glaucoma

Severe headache
Eye pain
Nausea and vomiting
Blurred vision
Halos around lights
Eye redness
If left untreated, glaucoma will eventually cause blindness. Even with treatment, about 15 percent of people with glaucoma become blind in at least one eye within 20 years.

When to see a doctor

Promptly go to an emergency room or an eye doctor's (ophthalmologist's) office if you experience some of the symptoms of acute angle-closure glaucoma, such as severe headache, eye pain, and blurred vision.
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What is Glaucoma?