To which of you that want to experience in a visual field test, and feel what happens in that dark room, I made a simulation of the test, for you to experiment in the feeling felt during the test.
At the bottom of this page you will see a simulation in which lights are projected on the round screen of the test. In order to experience the test as if in the clinic, follow the steps below:
Cover your left eye with your left hand, in a way the eye will be covered during the test.
Look with your open eye, (right eye) at the X on the center of the large grey circle in the picture at the end of this page.
Make sure your gaze stays centered on the X, its important the lights appear from time to time will not divert your gaze.
Place your right hand on the table and gently knock on it (so that a faint noise will be heard) whenever you see a circle of white light appears in the grey area of the test. Each time the circle will appear in a different location so that all of your visual field will be checked.
Remember that the test objective is to check if you see at the whole extent of your visual field, therefore you are requested to look the whole time at the central X, while the light are moving to a different location of your visual field unexpectedly.
In this simulation the lights will appear much stronger than in the real test where some of the lights will be so faint you won’t be able to see them at all. The reason of the faint lights (during the real test) is to identify the weakest light your eye can see.
Therefore, the projected lights at the test will be “the weakest lights you are capable of seeing” and “the strongest lights you are not capable of seeing”.
By comparing these two, the computer of the visual field test will be able to calculate the threshold of your vision at every point of your visual field.
Roll down this page and perform 10-20 knocks until you feel comfortable with the test, so you know what awaits you during the real test.
Good luck!
A simulation of a visual field test

Glaucoma & Cataract:



This website was written by Prof. Eytan Blumenthal, to better understand glaucoma & cataract. This information should not replace medical consultation.

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