Glaucoma is usually caused by a build-up of pressure in the fluid inside your eye. This can damage the optic nerve, which links your eye to your brain and enables you to see.
Glaucoma usually develops gradually, initially affecting the outer edge of your vision (tunnel vision) and, later, causing patchy or blurred vision. If undiagnosed or diagnosed too late, glaucoma can result in permanent blindness. However, this is less likely in the UK as many cases of glaucoma are picked up during a routine eye check.
Although it’s quite common, it mostly affects people in their 70s and 80s.
If your sight has been damaged by glaucoma, it can’t be repaired. However, once diagnosed, regular eye checks and eye drops to relieve the pressure of fluid in your eye should prevent further vision loss.
There are two main kinds of glaucoma – chronic (long-term) glaucoma and acute angle closure glaucoma.
Chronic glaucoma, also known as primary open angle glaucoma, is the most common. Initially symptomless, chronic glaucoma develops slowly.
Acute angle closure glaucoma is caused by a sudden increase in eye pressure. It's extremely painful and requires urgent medical attention to prevent permanent damage to your sight.
Other kinds of glaucoma are:
Chronic glaucoma can take years to develop. In fact, you may not realise there’s a problem with your sight as glaucoma symptoms are difficult to spot. However, you may notice your vision becoming blurred as glaucoma progresses.
Acute angle closure glaucoma happens without warning and can seriously damage your vision. Visit your nearest A&E department immediately if you have sudden, severe eye pain and any or all of the following:
Glaucoma symptoms are easy to miss, so it’s important to have a routine eye test every two years.
During your eye test, your optician will carry out glaucoma tests to check your vision, eye pressure and optic nerve. If glaucoma is detected, your optician will refer you to a specialist eye doctor called an ophthalmologist.
If your ophthalmologist confirms you have glaucoma, they’ll recommend treatment and regular follow-up appointments.
You’re more likely to develop glaucoma if:
To protect against further loss of vision, your ophthalmologist will recommend treatment to relieve your high eye pressure. In most cases, daily application of eye drops will prevent further damage.
However, your ophthalmologist may recommend laser treatment or surgery to drain the fluid which is causing your high eye pressure.