What is a glaucoma assessment?
Glaucoma is a group of eye conditions where damage to the optic nerve — usually caused by elevated pressure inside the eye — leads to gradual, irreversible loss of vision. It is the leading cause of irreversible blindness worldwide and affects around 700,000 people in the UK, with many more undiagnosed. A glaucoma assessment is a targeted evaluation that goes beyond a routine eye test to thoroughly investigate your risk and detect the condition at the earliest possible stage.
A comprehensive glaucoma assessment typically involves three key tests: tonometry (measuring the pressure inside your eyes), visual field testing (checking your peripheral vision for blind spots), and examination of the optic nerve head — either by direct observation through a dilated pupil or, increasingly, by OCT scan. Your optometrist will also consider risk factors such as your age, ethnicity (glaucoma is more common in people of African-Caribbean descent), family history, and the thickness of your corneas.
If you are aged 40 or over and have a parent, brother, sister, or child who has been diagnosed with glaucoma, you are entitled to a free NHS-funded eye test every year — and you should take up this offer. Early detection is critical because glaucoma damage cannot be reversed, only slowed or halted with treatment (usually daily eye drops or, in some cases, laser treatment or surgery). Many people with glaucoma have no symptoms until significant damage has already occurred, which is why regular screening is so important.
Who needs a glaucoma assessment?
- People aged 40 and over with a first-degree relative (parent, sibling, or child) who has glaucoma
- Anyone whose optometrist has found raised eye pressure or suspicious optic nerve appearance
- People of African-Caribbean descent (higher risk of developing glaucoma)
- Those aged 60 and over (risk increases with age)
- People with very high myopia (short-sightedness)
- Patients already diagnosed with glaucoma who need ongoing monitoring
- Anyone using long-term steroid medications (oral or eye drops)
What to expect during a glaucoma assessment
- 1Tonometry — measuring the pressure inside your eyes using a small instrument or puff of air
- 2Visual field test — pressing a button when you see lights flash in your peripheral vision
- 3Examination of your optic nerve using an ophthalmoscope or slit lamp with a special lens
- 4An OCT scan of the optic nerve and retinal nerve fibre layer may be performed
- 5Your corneal thickness may be measured (pachymetry) as this affects pressure readings
- 6Your optometrist will explain the results and, if necessary, refer you to a specialist
How much does it cost?
Free as part of an NHS-funded eye test for those at risk. Privately, £30–£60 depending on the tests included
How often should you have this test?
Annually for those at risk; every 6–12 months for diagnosed glaucoma patients under treatment