Visual acuity test

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Eye

Visual acuity test

Normal, near, and farsightedness

Overview

Risks

Results

Visual acuity test

Definition:

The visual acuity testis used to determinethe smallest letters a person can read on a standardized chart or card held 14- 20 feet away.

Alternative Names:
Eye test - acuity; Vision test - acuity
How the test is performed:

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This test may be done in a health care provider's office, a school, a work place, or elsewhere. Stand behind a line 20 feet from the eye chart. Remove glasses or contacts. Keep both eyes open and gently cover one eye with the palm of your hand, a piece of paper, or a paper cup while you read out loud the smallest line of letters that you can read on the chart.

If you are not sure of the letter, you may guess. This test is done on each eye, one at a time.If necessary, it is then repeated while you wear your glasses or contacts. You may also be asked to read letters or numbers from a card held 14 inches from your face. This will test your near vision.

How to prepare for the test:

No special preparation is necessary for this test.

For children, the preparation you can provide depends on your child's age, previous experiences, and level of trust. For general information regarding how you can prepare your child, see the following topics:

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.

Why the test is performed:

The visual acuity test is a routine part of an eye examination or general physical examination, particularly if there is a change in vision or a problem with vision. In children, the test is performed to screen for any visual problems. Vision problems in young children can often be corrected or improved. Undetected or untreated problems may result in permanent damage to vision.