Color vision deficiency means that your ability to
distinguish some colors and shades is less than normal. It occurs when
some of the color-sensitive cone cells in the retinas of your eyes do not work properly, causing inaccurate color information to be sent to the brain. About eight percent of men
and one percent of women are color deficient. Red-green deficiency (deuteranopia) is by far the most common form of color defect and it results
in the inability to identify certain shades of red and green. To many people with a red-green color defect, certain shades of red and green may appear as similar shades of grey. Those
with a less common type have difficulty distinguishing blue and yellow.
In very rare cases, color deficiency exists to an extent that no colors
can be detected, only shades of black, white and grey.
Since many learning materials are color-coded, it is important to
diagnose color vision deficiency early in life. Color vision testing is simple and painless, and usually involves identifying characters of different colors in a specially printed book, or putting a series of colored caps in the proper sequence. The
American Optometric Association recommends a comprehensive optometric
examination before a child begins school, so this problem can be detected and parents and teachers alerted.
Color vision deficiency is usually inherited and cannot be cured,
but those affected can often be taught to adapt to the inability to
distinguish colors. In some cases, a special red-tinted contact lens may be worn in one eye to help people with some kinds of color deficiencies telll the difference between certain colors. In some cases, developing a color vision defect where there was none before can be a symptom of certain types of eye or neurological disease. Consult your optometrist for more information and testing for color vision problems.
