What is Color Blindness?

Color Vision Deficiency, more commonly referred to as Color Blindness is the difficulty or the inability to distinguish certain shades of color. In severe cases, patients experience the world as black and white without any color at all. This is true color blindness, however very few people have actually been diagnosed as completely color blind. The more accurate term is color deficient and affects males more frequently than females.

Color deficiency is an inherited condition, but there are ocular diseases (glaucoma, cataracts, macular degeneration) that can cause deficits in color vision. For the majority of cases, genetics is the cause of color deficiency. Roughly 8% of white males are born with some type of color deficiency. Less than 1 % of females have color deficiency, however women are typically just carriers of the color deficient gene (x-linked recessive gene passed from mother to a son). This genetic cause is due to faulty development of the neural retinal cones (specific cells that perceive color) and their ability to transmit information to the optic nerve. The most important take away is that inherited color vision deficiency does not lead to additional loss of vision or blindness.

Color deficiency is diagnosed through a comprehensive eye examination through a test that utilizes psuedoisochromatic plates. In other words, a book with specially designed plates or pages includes hidden numbers or figures that can only be seen by persons with normal color vision. Most patients who have difficulty with this test can't differentiate between shades of red/green (most common) or blue/yellow (less common). Normal color vision patients can distinguish the numbers or figures easily whereas a color deficient patient will not.

It is common for a patient who has poor color vision to be unaware of the deficiency. We all learn to see the 'correct color'. Grass is green so color deficient individuals call the color they see the grass as green too, when it really looks brown. Also, parents of young children can miss that their child is color blind until they struggle with color vision testing. The majority of learning materials rely heavily on color perception so early detection is critical and accommodations can be made for the child during the critical phases of learning.

Treatment options for color deficient individuals are quite straight-forward. While there is no cure for inherited color deficiency using specially tinted spectacles or contact lenses can increase the ability to distinguish color. Most individuals compensate for this disorder in various ways such as organizing and labeling clothing with the help of family for ease of recognition. By knowing the order of things vs. their color improves the ability to correctly identify colors. A great example is the traffic light where red is on the top, yellow in the middle and green on the bottom.

Knowing if you or a loved one is color deficient is an important part of a comprehensive eye examination. This is especially important for any young children who are just beginning school. With 'back-to-school' coming up next month, it's a great time to schedule an annual eye examination.

Nothing on this web site is intended, nor should it be construed, as professional advice. Those reviewing the information should consult with a qualified professional.