Visual Field Testing (Perimetry) is the systematic assessment of visual function within the visual field. It is performed using a machine which displays objects in your peripheral vision while your eyes are fixated on a central target. It is a painless and non-invasive procedure which may take between 10 and 15 minutes to perform.
The ophthalmic assistant will ask you to place your head on a chin rest and look into a machine. You will then be presented with targets in your peripheral vision and prompted to press a button if you are able to see the target.
This test provides your ophthalmologist with a detailed map of your visual field which can be used to diagnose and monitor various neurological diseases such as stroke and brain tumours. It is especially important in patients with glaucoma, who need regular visual field tests to monitor their response to treatment.