This is a special procedure to do perimetry, i.e., measure visual fields. It is specifically indicated in Glaucoma. It is an automated perimetry, wherein repeated light stimulus of varying intensities appears in different parts of the field. Fields are charted on the basis of patient’s perception of these lights, while his/her eye is focused on a central spot. The results obtained from the patient are then compared with those of the age matched normal population and the amount of damage is quantified.
It is a simple, painless out patient procedure and takes only about 15 minutes. This test is invaluable in diagnosing, and monitoring the treatment in patients with glaucoma. A patient typically requires multiple sittings of this investigation over a period of time to monitor the progression of the disease.

It is also useful in certain neurological conditions and in some conditions affecting the optic nerve of the eye.