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Alternative names Return to top
Eye test - color; Vision test - color; Ishihara color vision testDefinition Return to top
A color vision test checks your ability to distinguish between different colors.How the test is performed Return to top
Your health care provider will ask you to sit in a comfortable position, and the test will be explained to you. You will be shown several symbols made of colored dot patterns. These dot patterns are on a background of randomly mixed colors.
You will be asked to identify the symbols, if possible.
You will cover one eye, and the tester will then show you the test plates, holding them 14 inches from your face, and ask you to quickly identify the symbol found in each color scheme.
How to prepare for the test Return to top
If your child is to have this test performed, it may be helpful to explain how the test will feel, and even practice or demonstrate on a doll. The more familiar your child is with what will happen and why, the less anxiety he or she will feel.
If you or your child normally wears glasses, wear them during the test.
With small children, distinguishing a red bottle cap from caps of a different color may be the test.
How the test will feel Return to top
The test is similar to a vision test.Why the test is performed Return to top
By using these plates, your health care provider can detect, classify, and estimate the degree of defect in your color vision.
In some circumstances, color vision testing is used to evaluate the function of the optic nerve. The optic nerve is the main nerve connecting the eye to the brain.
Normal Values Return to top
Normally all symbols are distinguished.What abnormal results mean Return to top
This test can determine the following abnormalities:What the risks are Return to top
There are no risks associated with this test. Update Date: 7/21/2003 Updated by: Edward B. Feinberg, M. D., Professor and Chair, Ophthalmology, Boston University School of Medicine, Boston, MA. Review provided by VeriMed Healthcare Network.
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Page last updated: 28 October 2004 |