Glaucoma can be primary, meaning there is no other underlying cause or secondary, meaning another disease is the reason for subsequent development of glaucoma.
There are two types of Primary Glaucoma:
This is the most common type of glaucoma where there is poor drainage of the aqueous fluid in the front part of the eye. This leads to building pressure inside the eye and subsequent damage to the optic nerve. The condition is painless and takes many years to evolve but leads to permanent loss of vision if not treated. This is the most common type of glaucoma in Australia.
- Narrow or closed angle glaucoma
If the front chamber of the eye is shallow, the iris base blocks the drainage angle and prevents fluid easily reaching the drainage tube. This leads to eye pressure build up which eventually damages the optic nerve.
This condition can present as an attack of acute angle closure glaucoma with sudden complaint of seeing haloes around light, blurred vision or severe eye pain. Vomiting can also occur if the eye pressure becomes very high. Immediate treatment is required to abort this attack of glaucoma by undergoing medical and eye laser treatment to open a hole in the iris allowing the aqueous fluid to escape (laser iridotomy). Our centre is equipped with a laser machine to perform this treatment promptly.
In many patients the condition develops slowly (chronic narrow angle glaucoma) with no pain but with ultimate damage to the optic nerve.
There are many causes of high eye pressure secondary to other conditions such as: pseudo exfoliation, pigment dispersion, viral or bacterial infection, inflammatory eye disease or genetic conditions.