Glaucoma is a disease of the optic nerve. The optic nerve sends signals from the eye to the brain. It is usually damaged by an increased pressure of fluid within the eye. Once damaged, the nerve cannot recover, which means glaucoma can lead to poor sight or blindness.
Glaucoma may be acute or chronic. Acute glaucoma occurs when the pressure in the eye rises quickly to very high levels. There may be sudden and severe eye pain with blurred vision and headache on the affected side. Chronic glaucoma is slow to develop and does not cause any symptoms in the beginning. As the nerve becomes more damaged, peripheral vision is lost until only ‘tunnel vision’ is left. Some people may become blind.
The different types of glaucoma are:
- Closed angle glaucoma – Happens slowly or suddenly, and can be painful
- Glaucoma suspect – Happens when there is a weak optic nerve, but no loss of vision
- Low pressure glaucoma – Happens slowly when the optic nerve is weak
- Open angle glaucoma – Happens slowly and is the most common form
- Other types – May be secondary to other eye conditions or some drugs (eg. steroids)