A visual field test is a way to measure what you can see above, below and all-around. Visual field tests are specifically used to detect areas of vision loss (blind spots). If you have previously had vision loss problems, these tests can also be used to monitor the progression.
What is a visual field test?
A visual field test is a simple test which measures your peripheral vision and all-around vision. The visual field machine will complete an analysis of the responses given during the test and collate these results in a visual plot field.
Why do I need a visual field test?
Your optometrist uses the visual plot field to compare your visual field test to others from people of a similar age, as well as looking for any loss of sensitivity across the visual field. This is split into two types: diffuse and localised. You can find out more about visual field test results interpretation here, including what an abnormal visual field test means.
What does a visual field test show?
The visual field machine will complete an analysis of the responses given during the test and collate these results in a visual field plot. This information will be used to look for any loss of sensitivity across the visual field. This is split into two types: diffuse and localised.
What can a visual field test detect?
Diffuse vs localised visual field test
A diffuse visual field defect happens when the overall sensitivity of the eyes is lower than average. This type of defect is commonly caused by a cataract, but it could also be due to not wearing the correct glasses during the test. That’s why your optometrist will consider your visual field results along with the results from other tests carried out during your eye exam.
A localised field defect happens when a particular area of the visual field has reduced sensitivity, so it’s harder for that person to detect the lights appearing in that location. There are certain patterns of localised visual field defects that are typical of different eye diseases, including glaucoma.
Noticed a change in your vision?
If you’re not sure whether you need glasses, or you’ve had a sudden change in your eyesight, a field vision test can help by measuring your all-around vision and detect any vision problems you might have. Symptoms of eye problems are not always obvious, so it’s important to have your eyes tested regularly.