What exactly is the examination of the visual fields?
The examination of optical perimetry (visual fields), is, undoubtedly, the most widespread examination of the functionality of the optic nerve. The technology is based on recognition of a number of light stimuli of various dimensions, which are appropriately displayed by the diagnostic system. The examination of the visual fields is directly related to the diagnosis and monitoring of glaucoma, but also in investigating neurological diseases.
The whole process is painless and takes about 10 minutes. It does not require any preparation of the patient (e.g., drops). The examination is actually studying not the central vision (i.e. how well you see) but the peripheral vision (i.e. how well we understand the surrounding environment).
How is the examination of the visual fields performed?
The examination of optical perimetry is performed in a relatively dark room, separately for each eye. The patient’s head is placed in a machine with a large white dome. The patient holds hand a special button in their hand (joystick) which they press whenever the dome of the machine shows bright object (while they focus on a specific luminous target located just opposite them).
The subject should not move the test eye (not looking for and pressing the button only when they see the light in the peripheral field of vision), otherwise the credibility of the examination is affected. The lights can be strong or weak, in various parts of the site and some of them check if you are focused. The result helps the ophthalmologist in the diagnosis and monitoring of your condition.