What is Glaucoma?

Glaucoma is an eye condition resulting in irreversible optic nerve damage. The condition can affect your vision so gradually that you may not notice any loss of vision until the disease is at an advanced stage. Therefore, early diagnosis and treatment are key in minimising or preventing optic nerve damage and limiting related vision loss.


There are several types of glaucoma which can affect the eye, and these are typically classified as follows:

1 Open-angle Glaucoma

Open-angle glaucoma happens when the drainage canals become clogged over time or when the tissues around the canals harden. Poor fluid drainage out of the eye results in increased eye pressure. Most patients have no symptoms and no early warning signs.

Initially, open-angle glaucoma has no symptoms and causes no pain. It can develop in one or both eyes. Without treatment, individuals will slowly lose their peripheral (side) vision. As it remains untreated, people may miss objects to the side and out of the corner of their eye. They seem to be looking through a tunnel. Over time, straight-ahead (central) vision may decrease until no vision remains.

2 Angle-closure Glaucoma

Angle-closure glaucoma is caused by a shallow space between the iris and cornea. Fluid drainage is obstructed if the iris slips forward. This condition is triggered by medication that dilates the pupil or occurs naturally when the eye dilates in low lighting. Hyperopic (Long-sighted) patients are at a higher risk because their eyes have narrow drainage angles. Symptoms include severe eye pain, blurred vision, nausea and vomiting.

Those more at risk of developing angle-closure glaucoma include:
• Anyone with hyperopia (long-sightedness)
• Women (4 times more likely)
• Anyone over the age of 50

3 Low-tension Glaucoma

Low-tension glaucoma is a condition in which the optic nerve is damaged and vision loss has occurred despite normal pressure in the eye.

4 Congenital Glaucoma

Congenital glaucoma is present at the time of birth.