What’s this test? Visual field test

A visual field test assesses your peripheral or side vision.

There are a variety of ways to assess peripheral vision. A screening test is often done during a comprehensive eye exam. The optometrist will ask you to look straight ahead while they hold up fingers at the edge of your vision, then ask how many fingers you see. If a more formal test is required, you may be asked to do a visual field test involving an instrument called a perimeter.

An optometrist may recommend visual field testing to a patient who has, or is suspected of having, an ocular condition such as glaucoma, a retinal disorder such as macular degeneration, or another disease of the optic nerve. Patients who have, or are suspected of having, neurological (brain) conditions affecting their vision, such as a tumour or stroke, may also be recommended for visual field testing.

You may not feel you have a problem with your peripheral vision. However, because we mostly rely on our central vision, it can be difficult to notice subtle changes such as increased blurriness at the edges of your vision.

Patients may be asked to have repeat visual field tests, often more than once a year. Repeating a test allows the optometrist to confirm any loss of vision and to monitor for any improvement, stability or worsening of vision.

A visual field test is non-invasive. Patients are asked to sit in front of an instrument with a bowl-shaped screen. Typically, one eye is covered so each eye can be tested individually, though both eyes might be tested together under some circumstances. Sometimes a lens may be placed in front of the eye being tested.

With your face comfortably positioned against a chin and forehead rest, you will be asked to stare at a dot straight in front of you. If you have difficulty with central vision – for example, if you have macular degeneration – you may be asked to look at the centre of four lights.

Lights will flash in different parts of your field of vision – above, below and at the sides of your central vision. You will be asked to click a button every time you see a light. Some lights will be brighter or duller than others and some will flash for longer than others. Don’t worry about missing any lights – the same points are tested multiple times to ensure an accurate result.

Depending on the test you’re having, the lights may be static or they may move. They may run in an automatic random pattern or the technician may manually choose particular areas of your visual field to test.

Testing usually takes about five minutes per eye, but additional time will be needed to set up, switch eyes, etc.

You don’t need to do much to prepare. However, keep in mind that you need to be alert and focused, so it’s best not to schedule the test when you’re likely to be tired, i.e. at the end of a long workday.

If you wear glasses, please bring them in for your test. If you wear contact lenses, you can usually do the test while wearing your contact lenses.

You will not normally get dilating eye drops before a visual field test. However, if you are doing a visual field test shortly after a dilated eye exam, don’t worry – the test can be adjusted to compensate for the effects of dilating eye drops.

The most important thing to remember during the test is to keep looking straight ahead rather than letting your gaze move around, because the point is to test your peripheral vision.

Your optometrist will review the test results and then go over them with you. Depending on why you were tested and the results, the optometrist may discuss a treatment or management plan with you.

If you have a condition where improvement is possible, you will be scheduled for repeat testing to monitor for these changes. If you have a condition where vision loss cannot be reversed, repeat testing will determine if vision loss is stable or worsening.

Visual field testing is done at the Waterloo clinic, located (until the permanent location reopens) at Unit C, 419 Phillip St., Waterloo. Learn more about the construction and interim clinic location.

We have two visual field instruments – a Humphrey Visual Field Analyzer for automated testing and a Goldmann Perimeter for manual testing. The type of visual field test you receive will depend on what condition or disease you have (or are suspected to have) and its progression.

A visual field test isn’t a standard part of a comprehensive eye exam, so there is a separate fee. As of early 2025, an automated test costs $60 and manual testing costs $105. These fees are subject to change. OHIP may cover the cost of visual field testing for patients with conditions such as glaucoma or certain brain conditions affecting the vision. Some private insurance plans may also cover the cost of testing.

A visual field test is done by our Imaging Service, so you will typically need to book separate appointments for the test and for consultation with the optometrist.

If you need multiple tests – i.e. a visual field test and an OCT scan of the retina – it is usually possible to book these back to back. For example, the visual field test might take 15 minutes and the retinal scan might take 15 minutes, with both taking place during one 30-minute appointment.

• What you should know about: Glaucoma
• What you should know about: Macular degeneration
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