What is a visual field?
The visual field is the section of space that the eye can distinguish around a fixed point.
The objective of examining the visual field is to draw this space when the eye fixes an immobile point straight ahead to determine the range of space that each eye can see (the ability to see in the center and on the sides).
It is the only test capable of understanding the functioning of the optic nerve, making it possible to see whether a visual or neurological pathology has affected peripheral (since the patient is not aware of the deficits) or central (to assess the importance of 'a scotoma).
How is the exam going?
The patient is installed in a room protected from light and noise. The device is suitable for patients with reduced mobility or in a wheelchair.
To exercise this type of exam, no preparation is necessary.
The orthoptist will install you in front of the device and explain the course of the examination. She will answer your questions and remain present for the duration of the measurement.
You will be asked to fix a light point for the duration of the exam. Several visual stimuli will appear, you will have to press a joystick each time you perceive these stimuli.
Why and when to make a visual field?
This examination is essential for the diagnosis of glaucoma. It helps to define the stage of the disease. Annual or bi-annual exams will then be requested in order to follow the evolution of the pathology and thus best adapt the treatment of the patient.
It is also possible to perform a binocular and kinetic visual field in the context of neuro-ophthalmological disease.
Other pathologies affecting the optic nerve can be detected during this examination (intracranial tumor, cerebrovascular event, intracranial hypertension, retinitis pigmentosa).
An examination of the visual field can also be requested in order to assess the capacities to drive certain vehicles, to practice a sport and to detect an ophthalmological impairment linked to certain drug treatments (synthetic antimalarials, antiepileptics, anti-tuberculosis drugs) .
To note :
The total duration of the examination (installation and explanation included) does not exceed 20 to 30 min and each eye is tested alternately.