Glaucoma types

Glaucoma typesGlaucoma types

Glaucoma types

There are several types of glaucoma. The two main types are open-angle and angle-closure.

These are marked by an increase of intraocular pressure (IOP), or pressure inside the eye.

Open-angle glaucoma, the most common form of glaucoma, accounting for at least 90% of

  • Is caused by the slow clogging of the drainage canals, resulting in increased eye pressure
  • Has a wide and open angle between the iris and cornea
  • Develops slowly and is a lifelong condition
  • Has symptoms and damage that are not noticed.

“Open-angle” means that the angle where the iris meets the cornea is as wide and open as it should be.

Open-angle glaucoma is also called primary or chronic glaucoma. It is the most common type of glaucoma, affecting about three million Americans.

Angle-Closure Glaucoma


  • Is caused by blocked drainage canals, resulting in a sudden rise in intraocular pressure
  • Has a closed or narrow angle between the iris and cornea
  • Develops very quickly
  • Has symptoms and damage that are usually very noticeable
  • Demands immediate medical attention.

It is also called acute glaucoma or narrow-angle glaucoma.

Unlike open-angle glaucoma, angle-closure glaucoma is a result of the angle between the iris and cornea closing.

Normal-Tension Glaucoma (NTG)


In normal-tension glaucoma the optic nerve is damaged even though the eye pressure is not very high.

We still don’t know why some people’s optic nerves are damaged even though they have almost normal pressure levels.

This type of glaucoma occurs in babies when there is incorrect or incomplete development of the eye’s drainage canals during the prenatal period. This is a rare condition that may be inherited. When uncomplicated, microsurgery can often correct the structural defects.

Other cases are treated with medication and surgery.


eye-health-3___SourceThe two main types of glaucoma are primary open angle glaucoma (POAG) and angle closure glaucoma, but there are several other types of glaucoma.

  • Primary Open Angle Glaucoma- the most common type of glaucoma and it is hereditary. The optic nerve is damaged due to an increase of intraocular pressure (IOP), or pressure inside the eye. This type of glaucoma develops slowly and sometimes without noticeable sight loss for many years because there are no symptoms or warning signs. It usually responds well to medication, especially if caught early and treated.
  • Angle Closure Glaucoma- more rare and is very different from open angle glaucoma in that the eye pressure usually rises very quickly. Symptoms of angle closure glaucoma may include headaches, eye pain, nausea, rainbows or halos around lights at night, and very blurred vision.
  • Normal Tension Glaucoma-when optic nerve damage has occurred despite an increase in eye pressure
  • Secondary Glaucoma- any case in which another disease causes or contributes to increased eye pressure, resulting in optic nerve damage and vision loss.
  • Pediatric Glaucoma- consist of congenital glaucoma (present at birth), infantile glaucoma (appears during the first three years), and juvenile glaucoma (age three through the teenage or young adult years). The range of treatment is very different from that for adult glaucoma, so it is very important to catch pediatric glaucoma early in order to prevent blindness.