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Eye Test
An eye test checks your vision and the health of your eyes. As well as measuring sight, it can detect eye conditions and sometimes signs of other health problems.
Quick answer
Eye Test: what it is and what the results mean
An eye test (sight test) assesses how well you see and examines the health of your eyes. It includes checking your vision, eye pressure, and looking at the structures inside and at the back of the eye.
- Why it is done: It is used to check and correct vision with glasses or contact lenses, to detect eye conditions such as glaucoma, cataracts and macular problems, and sometimes to reveal signs of conditions like diabetes or high blood pressure.
- Understanding results: Results show whether you need glasses or a change of prescription and whether your eyes are healthy.
What it is
An eye test (sight test) assesses how well you see and examines the health of your eyes. It includes checking your vision, eye pressure, and looking at the structures inside and at the back of the eye.
Why it is done
It is used to check and correct vision with glasses or contact lenses, to detect eye conditions such as glaucoma, cataracts and macular problems, and sometimes to reveal signs of conditions like diabetes or high blood pressure.
What to expect
You read letters on a chart, and the optometrist uses instruments and lights to examine your eyes and measure pressure. Sometimes drops are used to widen the pupils for a clearer view, which can blur vision for a few hours.
Understanding the results
Results show whether you need glasses or a change of prescription and whether your eyes are healthy. If a problem is found, you may be advised on treatment or referred to a specialist for further assessment.
Good to know
Risks and limitations
Eye tests are safe and painless. If pupil-widening drops are used, vision may be blurred and light-sensitive for a few hours, so you may need someone to drive you home.
Education and reference only. This explains the test in general terms and is not medical advice. Always follow the specific instructions from the team arranging your test, and discuss your results with your clinician.
Answers
Eye Test: frequently asked questions
How often should I have an eye test?
Many people are advised to have an eye test around every two years, or more often if recommended or if you notice changes in your vision. Your optometrist will suggest how frequently you should be seen.
Can an eye test detect other health problems?
Yes. Examining the back of the eye can reveal signs of conditions such as diabetes, high blood pressure and, occasionally, other health problems, as well as eye-specific diseases like glaucoma.
Related tests
Other other investigations
Sources
Where this is drawn from
- NHS — Tests and treatments
- NICE — diagnostic guidance
- Relevant royal college / professional body
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