Glaucoma refers to a group of eye disorders that can all cause damage to the optic nerve that carries information from the eye to the brain.

Glaucoma usually has few or no initial symptoms. This is why eye checkups should be scheduled regularly.

In the majority of cases, glaucoma is associated with having higher-than-normal pressure inside the eye. But it can also occur when intraocular pressure (IOP) is normal.

If it goes untreated or uncontrolled, glaucoma can cause peripheral vision loss and can even lead to blindness.

Types of Glaucoma and Symptoms

Primary open-angle glaucoma.

• This common type of glaucoma gradually reduces your peripheral vision without other symptoms. By the time you notice it, permanent damage already has occurred.
  
• If your IOP remains high, the loss of your vision can progress until tunnel vision, and you will be able to see only objects that are straight ahead.
• Ultimately, all vision can be lost, leading to blindness.

Acute angle-closure glaucoma.

• This is also called narrow-angle glaucoma.
  
• This type of glaucoma produces sudden symptoms such as eye pain, headaches, halos around lights, dilated pupils, vision loss, red eyes nausea and vomiting.

Normal-tension glaucoma.

• Normal-tension glaucoma is a type of open-angle glaucoma that can cause visual field loss due to optic nerve damage.
  
• In normal-tension glaucoma, the eye’s IOP remains in the normal range.
• Pain is unlikely and permanent damage to the eye’s optic nerve will most likely not be noticed until symptoms such as tunnel vision occur.
• The cause of normal-tension glaucoma is still not known. Many doctors believe it is related to poor blood flow to the optic nerve.
• Normal-tension glaucoma is more common in those who are Japanese, are female and/or have a history of vascular disease.

Congenital glaucoma.

• This is an inherited form of glaucoma, and is present at birth, with 80 percent of cases diagnosed by age one.
• Children diagnosed with this type of Glaucoma are born with narrow angles or another type of defect in the drainage system of the eye.
• It’s hard to spot the signs of congenital glaucoma, because children most likely do not understand what is happening to them or notice the changes in vision.
• If you notice a cloudy, white, hazy, enlarged or protruding eye in your child, talk to your eye doctor.