Your visual field refers to how much you can see around you, including objects in your peripheral (side) vision.

This test produces a map of your field of vision. Visual field tests help your ophthalmologist (Eye M.D.) monitor any loss of vision and diagnose eye problems and disease.

How is a visual field test performed?
The test is performed with a large, bowl-shaped instrument called a perimeter. In order to test one eye at a time, one of your eyes is temporarily patched during the test. You will be seated and positioned comfortably in front of the perimeter and asked to look straight ahead at a fixed spot (the fixation target). The computer randomly flashes points of light around the bowl-shaped perimeter. When you see a light, press the indicator button. It is very important to always keep looking straight ahead. Do not move your eyes to look for the target; wait until it appears in your side vision. It is normal for some of the lights to be difficult to see. A delay in seeing a light does not necessarily mean your field of vision is damaged.

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