What are the different types of glaucoma?
The main types of glaucoma are:
- Primary open angle glaucoma is the most common type of glaucoma in the UK. It’s also known as chronic open angle glaucoma which means the damage to your optic nerve and changes to your sight happen very slowly over time.
- Acute closed angle glaucoma happens when your eye pressure rises very suddenly, which can cause damage to your optic nerve over a very short space of time. It happens when the outer edge of the iris is pushed forward by the aqueous fluid (a clear, watery fluid that flows between the lens and the cornea) behind it. This causes the iris to come into contact with the cornea, closing the drainage angle. This stops the aqueous fluid from draining away altogether.
- Normal tension glaucoma occurs when your eye pressure is within normal range, but causes damage to your optic nerve. It’s not entirely known why some people’s optic nerve becomes damaged even though their eye pressure is at a normal level. It’s thought that perhaps some people’s optic nerve may just be weaker or have a more fragile blood supply, and unable to cope with an eye pressure within the normal range.
- Secondary glaucoma is caused by the effect of another eye condition, an injury to the eye, or certain treatments, medications or operations.
- Congenital glaucoma is a rare form where a baby is born with glaucoma because their drainage system didn’t develop properly before birth. Congenital glaucoma is usually treated early on in life, usually with surgery, and is managed by specialist clinics.
- Ocular hypertension (high eye pressure) happens when people have eye pressure above the normal range, but the pressure doesn't cause any damage to the optic nerve. This is called ocular hypertension rather than glaucoma. If you have ocular hypertension, it can increase your risk of developing glaucoma so this needs to be monitored.
For more information on glaucoma see What is glaucoma?
