Visual field test
What is your visual field?
Your visual field is how wide of an area your eye can see when you focus on a point. In terms of its examination, we distinguish between central and peripheral fields.
The peripheral visual field helps you to navigate. Although peripheral vision is not capable of distinguishing fine details, it perceives movement and, to some extent, colors. The central field allows for sharp vision, facial recognition, and color .
What is visual field loss?
Visual field loss is a condition associated with a decrease in the patient’s vision due to damage to the visual tract. Visual field loss can occur both on the periphery and near the center of vision. In the case of central visual field loss, the patient may not notice anything of it because the loss of vision in one eye is compensated by the other eye due to the overlapping visual fields of the two eyes.
Larger visual field loss (when the visual field is significantly narrowed compared to the healthy one) can usually be caused by various hereditary atrophic diseases of the optic nerve or cataracts.
What does visual field examination mean?
During the visual field examination, we examine the eyes with a special perimetry test. We examine the area that the patient sees with both eyes when his head is upright and motionless.
In doing so, we measure the extent of the loss of vision, if any, by covering the eyes individually.
Why is it important to take the visual field test?
When do you need a visual field test?
Visual field test is required to diagnose the following diseases or cases:
- Cataract disease
- Central nervous system diseases affecting vision
- Tumors affecting the choroid and retina, inflammatory processes
- Circulatory disorders of the eye
- Inflammatory, circulatory and toxic diseases of the optic nerve
- Inherited eye diseases
- Obtaining and renewing a professional license
How does the test work?
The test takes about 15-20 minutes.
During the examination, the medical assistant maps your vision field to each eye separately using a computer.
The vision field test is especially important in case you use reading glasses.
During the test, it is very important that you only look at the center light. In the peripheral vision field, points flash here and there alternately, which you must signal to your examining doctor without looking straight to the points. Some points are checked several times. The same process is repeated for the other eye.