Visual field
Key points
- The visual field is the total area in which objects can be seen in the peripheral vision while the eye is focused on a central point.
- Confrontation visual field exam: A quick and basic evaluation of the visual field done by an examiner sitting directly in front of you.
- Adults: No special preparation is necessary for these tests.
- The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experiences, and level of trust.
Alternative names
Perimetry; Tangent screen exam; Automated perimetry exam; Goldmann visual field exam; Humphrey visual field exam
Definition
The visual field is the total area in which objects can be seen in the peripheral vision while the eye is focused on a central point.
How the test is performed
Confrontation visual field exam: A quick and basic evaluation of the visual field done by an examiner sitting directly in front of you. With one eye covered, you are asked to look at the examiner's eye and tell when you can see the examiners hand.
Tangent screen exam: You will be asked to sit about 3 feet from a screen with a target in the center. You will be asked to stare at the central target and let the examiner know when you can see an object brought into your peripheral vision. The extent of your peripheral vision is mapped.
Automated perimetry: You sit in front of a concave dome and stare at a central target within the dome. A computer-driven program flashes small lights at different locations within the dome's surface, and you press a button when you see the small lights in your peripheral vision. Your responses are compared to age-matched controls to determine the presence of defects within the visual field.
How to prepare for the test
Adults:
No special preparation is necessary for these tests.
Children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experiences, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:
- Toddler test or procedure preparation (1 to 3 years)
- Preschooler test or procedure preparation (3 to 6 years)
- Schoolage test or procedure preparation (6 to 12 years)
- Adolescent test or procedure preparation (12 to 18 years)
How the test will feel
There is no discomfort with this test. Some visual field tests take a long time and may be tiring.
Why the test is performed
The test will detect any loss of peripheral vision and provide a map of that loss which will be helpful in diagnosing the cause.
Normal Values
The peripheral vision is normal in extent.
Written and revised by
Gerald Hurowitz, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
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