The eye is a ball filled with fluid under pressure. The fluid is constantly made within the eye and drains out through small holes in the internal angle of the eye into the venous system.

The pressure of the fluid is usually maintained quite constant so that we may see clearly. As we age, the drainage holes can narrow and the fluid drains away less readily, leading to a rise in pressure.

If this pressure rise is high or if it is maintained for some time, it can damage the nerves as they enter and leave the eye, leading to loss of peripheral vision in the early stages and ultimately to complete loss of vision. This process is known as glaucoma.

Glaucoma may be acute or chronic.

Acute glaucoma comes on rapidly and causes symptoms of pain in the eye, haloes around lights, and blurred vision. Most people realise something is seriously wrong and seek help quickly. The condition is treatable with eye drops, tablets and laser. Sometimes surgery is required. If treated early, permanent damage can be prevented.

Chronic glaucoma is much more common and causes no symptoms at all until significant permanent damage has occurred. This is why it is so important to have regular eye health checks, for everyone over 40 and even earlier if there is a family history of glaucoma or your eye has been injured.

 The diagnosis is made by measuring eye pressures, examining and recording the appearance of the optic nerves and measuring the peripheral vision.

Treatment usually consists of eye drops used every day for the rest of your life. Some of these drops reduce the production of the fluid, such as Timolol. Others increase the drainage of the fluid, such as Xalatan. All drops are drugs and may cause side effects. Your doctor will discuss these with you. If you experience any problems you must discuss these with doctor.

Regular checks are required to ensure the drops are effective, reducing the pressure to a safe level that is causing no further harm to your optic nerves and to make sure the drops are causing you no harmful side effects.

Sometimes treatment with laser or surgery is required and doctor will discuss this with you if necessary. Please discuss any questions you may have with your doctor.