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Color Blindness: An Overview


Color blindness is a condition impacting the capability to see colors under normal light or to perceive colors as they are normally seen. Usually, the condition is present at birth, but it can also result from old age or a number of diseases of the eye.


The discernment of color is dependent upon the cones found in the eye's macula. People are commonly born with three types of cones, each perceiving various wavelengths of color tone. With shades of color, the length of the wave is directly related to the resulting color. Long waves are seen as reds, moderately-sized waves are seen as greens and short waves are perceived as blue tones. Which type of cone is involved has an impact on the spectrum and level of the color blindness.


Since it is a gender-linked recessive trait, green-red color deficiency is more frequent in males than in women. Nevertheless, there are a small number of females who do experience varying degrees of color blindness, particularly yellow-blue deficiencies.


Some individuals acquire color blindness later on as a result of another condition including macular degeneration, glaucoma and aging. Thankfully, it could be possible to restore color vision if the underlying cause is corrected.


There are several tests for the condition. The most widely used is the Ishihara color exam, named after its inventor. For this test a plate is shown with a group of dots in a circle in seemingly random sizes and colors. Within the circle one with proper color vision can see a numerical figure in a particular tint. The patient's capability to make out the digit inside the dots of contrasting shades indicates the level of red-green color blindness.


While hereditary color blindness can't be corrected, there are some options that can help to make up for it. For some, wearing colored contacts or glasses which block glare can help to perceive the differences between colors. Increasingly, computer applications are being developed for standard computers and even for mobile machines that can help people enhance color distinction depending on their specific diagnosis. There is also interesting research being conducted in gene therapy to enhance color vision.


The extent to which color vision problems limit an individual depends on the kind and severity of the deficiency. Some patients can accommodate to their condition by familiarizing themselves with substitute clues for colored objects or signs. For example, many people can learn the order of traffic signals or contrast items with color paradigms like the blue sky or green trees.


If you notice signs that you or your family member could have a color vision deficiency it's important to schedule an appointment with an eye doctor. The sooner you are aware of a problem, the easier it will be to manage. Contact our Knoxville, TN eye care practice for information about scheduling an exam.