When you look at something you not only see the object you are looking at, but you can see all around it. The area that you can see (without moving your head or eye) is called your visual field. In each eye it extends from the object you are looking at, to about 95º out to the sides, 60º upwards, 75º downwards and 60º towards your nose.

The visual field test can be a good indication of the health of your eyes and indeed the whole of your visual system (i.e. retina, nerves and parts of the brain). It is, therefore, a useful part of the eye examination. For example, it is used in the diagnosis and monitoring of glaucoma but it can show up many other problems as well.

The visual field test is done using a piece of equipment called a visual field screener (sometimes known as an auto-perimeter) of which there are many types. We use the Humphry Field Tester which is considered the gold standard in the industry. During the test you have to look at a little spot in the centre of the machine (to keep your eye still) and respond pushing a hand held button when you see the target (usually a light that flashes on and off once), which will appear somewhere else on the screen.

Threshold visual field testing is used to detect many diseases of the optic nerve and parts of the brain and re-inforces our committment to provide you with the best ocular health diagnosis.