An essential guide

Glaucoma is a group of eye conditions that can damage the optic nerve at the back of the eye. If left untreated, your peripheral vision will gradually get worse and can lead to blindness. Glaucoma affects 1-2% of the population over 40 years of age. Many of these patients are unaware of the presence of the condition in its early stages.


The pressure inside the eye can rise if the amount of fluid being produced by your eye is not balanced by the fluid draining out of the eye. If there is too much pressure in the eye the optic nerve can become damaged.

A very high pressure could damage the nerve immediately (acute glaucoma). A lower level of pressure can cause damage more slowly, leading to a gradual reduction in sight if left untreated. Some people with normal pressures and vulnerable optic nerves may also develop glaucoma.

Detecting glaucoma

Glaucoma can be detected during your routine eye examination, during which certain screening tests are carried out. These may include some or all of the following:

  • Examination of the back of the eye (retina). This may be done by shining a light into your eyes and taking a photograph of the retina.
  • Measuring the pressure in your eye. There are different tests to measure eye pressure. The 'puff of air' test, or a test using eye drops may be carried out.
  • Checking your field of vision. This is the 'spot of light' test.  You will be asked to look at a screen and indicate when you see spots of light.

Is there any treatment for glaucoma?

If any of the results are suggestive of glaucoma you will usually be referred to an ophthalmologist who can diagnose the condition and start any treatment.

Treatment for chronic glaucoma is usually with eye drops. Laser treatment or surgery may be necessary in some cases. The good news is that once it is detected and treated, although someone cannot be cured of glaucoma, most people retain useful vision for a lifetime.

Risk factors for glaucoma

Some factors put you more at risk of getting glaucoma:

Age: Glaucoma becomes more common the older you get. It is rare under the age of 40.
Family History: You are at a higher risk if you have a close relative with the condition.
Race: People of African origin are at a higher risk of developing glaucoma. It may start at an earlier age and be more severe.
Diabetes: Diabetics are at an increased risk of developing glaucoma.
Eyesight: People with high levels of short-sightedness are at a higher risk of developing chronic glaucoma. Long-sighted people are more at risk of developing acute glaucoma which may be detectable through a routine eye test before any increase in eye pressure.

Who should be tested?

In most cases of glaucoma there is no pain and in the early stages your vision may seem unaffected. NHS eye examinations are free for everyone in Scotland. It is important that everyone should have a regular eye examination every 2 years, or if you over 60, have family history of glaucoma or are diabetic, we recommend annual examinations.

Optical coherence tomography

At Black and Lizars we can also use OCT scanning technology to look at microscopic changes to the optic nerve. An OCT scan is as simple as taking a photograph. Monitoring your optic nerve like this allows us to refer you accurately as soon as changes appear.

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