What are the Different Types of Glaucoma?

Chronic Open-Angle Glaucoma

This is the most common form of glaucoma. It occurs as a result of aging.
The drainage angle of the eye becomes less efficient with time, and pressure within the eye gradually increases. An increased pressure in the eye can cause a decrease in blood flow which may result in optic nerve damage.

If this increased pressure results in optic nerve damage,
it is known as chronic
open-angle glaucoma. Over 90% of adult glaucoma patients have this type of glaucoma.

Chronic open-angle glaucoma damages vision so gradually and painlessly that you are not aware of trouble until the optic nerve is already badly damaged.

Angle-Closure Glaucoma

Sometimes the drainage angle of the eye may become completely blocked.
It is as though a sheet of paper floating near a drain suddenly drops over the opening and blocks the flow out of the sink. In the eye, the iris (the part that makes eyes blue or brown) may act like the sheet of paper closing off the drainage angle.

When eye pressure
builds up suddenly,
it is called acute
angle-closure glaucoma.

Symptoms of Glaucoma may include:

         Blurred vision
         Severe eye pain
         Headache

Rainbow haloes around lights
Nausea and vomiting

If you have any of these symptoms, call your ophthalmologist immediately.

Unless an ophthalmologist treats acute angle-closure glaucoma quickly, blindness can result. Acute angle closure glaucoma is more common in Asian people than in people of European descent; it is rare in people of African descent.

In some patients' glaucoma has features of both the chronic open angle type and the acute angle closure type. This may be called chronic angle closure glaucoma or mixed mechanism glaucoma. It occurs more frequently in people of African and Asian descent.