Glaucoma is an eye condition often, but not always, associated with pressure building up in the eye. Below we explain what causes glaucoma and when you should be concerned.
What is glaucoma?
Glaucoma is the name given to a group of eye conditions where the optic nerve at the back of the eye is damaged. It is often linked with raised pressure within the eye, although eye pressure can sometimes be normal. When the nerve is damaged, it can start to cause problems with the peripheral vision (side vision), and if left untreated can cause permanent damage. With early treatment, further damage to vision can be prevented. The condition often happens in both eyes, sometimes affecting one eye more than the other. Glaucoma is one of the leading causes of severe sight impairment.
There are several types of glaucoma – open-angle (chronic) glaucoma and closed-angle (acute) glaucoma are the main types associated with high eye pressure. However, normal-tension glaucoma also causes similar damage to the nerve without raise eye pressure. Even though there are many different causes of the disease, the outcomes are very similar. Glaucoma may not have symptoms, and this is why it is very important to have regular sight tests.
Age is the biggest risk factor for glaucoma. However, your risk also increases if you have family members with glaucoma or if you are of black African or black Caribbean ethnic origin. Other eye conditions can sometimes cause glaucoma as a side effect. If you are diagnosed with glaucoma, it is important to let your close relatives know as they may be at increased risk of developing the disease.
The danger with open-angle or chronic glaucoma is that, in the early stages, your eyesight may seem perfectly normal. There is no pain, but your peripheral vision (side vision) is being damaged. Eventually, your central vision can be affected. It is important to have regular sight tests as open-angle glaucoma often does not have symptoms.
Symptoms of closed-angle glaucoma can develop very quickly. Your eye might become very red and painful, you may get headaches and feel sick, and you may notice coloured halos around lights. This is a medical emergency. If you notice any of these symptoms, you should contact us for advice immediately.
The nerve sustains damage by mechanisms other than high pressure in the eye, such as poor perfusion of blood to the nerve. The eye pressure will be normal but the nerve will still be affected and the visual field can be damaged.
Open-angle glaucoma and normal-tension glaucoma are usually treated with eye drops which reduce the pressure in the eye. You will need to use these daily and you will be monitored regularly at the hospital.
Occasionally people with open-angle glaucoma need surgery to control the pressure.
Closed-angle glaucoma can damage the eye quickly. It is initially treated with drops and medication, and sometimes by drugs directly into the bloodstream to quickly reduce the pressure in the eye. Laser treatment is often needed to allow the fluid to flow through the eye more effectively. People with closed-angle glaucoma may need surgery if laser treatment is not successful.