Getting to the Root of Color Blindness
For most people, the vast array of colors we see every day is something that usually gets taken for granted. We describe objects everyday by pointing out their various patterns and hues, and it is difficult to even imagine what the world would be like without them. However, for a small but significant minority this is not the case. An estimated 8% of the male population (and about 0.5% of women) suffer from some form of color blindness, and for them the world can look very different. At Georgia Eye Physicians and Surgeons, we treat all forms of visual impairment and understand the specific needs of those suffering from this relatively common condition.
When we see, light reflected off objects in the outside world is focused, via the eye’s lens, onto the retina, a layer of millions of tiny, light-sensing, nerve cells located at the back of the eye. The cone cells, which are concentrated at the center of the retina and are primarily responsible for distinguishing colors and fine details, come in three varieties. Each type of cone is sensitive to specific range of light wavelengths: one perceives blue light, another perceives green, and the third perceives red. By recognizing and interpreting varying combinations of these three basic pigments, the brain is able to distinguish all of the colors that make up the visible spectrum.
People with normal color vision have all three types of cones present and working together, but color blindness is the result when one or more of the cone types are faulty or absent, making it difficult for the eye to distinguish between certain specific colors. For example, without red-sensitive cones the eye would be unable to see colors containing red clearly. There are several different forms of color blindness, each differentiated by the particular colors involved. People suffering from protanopia are unable to perceive any ‘red’ light, those with deuteranopia are unable to perceive ‘green’ light, and those with tritanopia are unable to perceive ‘blue’ light. People with both red and green deficiencies, the most common forms, live in a world of murky greens where blues and yellows stand out. Browns, oranges, and shades of red and green are easily confused, resulting in the common term “red-green color blindness.”
While the various forms of color blindness are most commonly genetic, they can also, in some cases, be caused by external factors. Eye problems, such as glaucoma, macular degeneration, cataracts, or diabetic retinopathy, traumatic injury to the eye, the side effects of some medicines, and even simple deterioration associated with age can all produce similar symptoms. Although inherited color blindness cannot be reversed or corrected, there are some treatments that can help minimize the symptoms. Colored contact lenses can sometimes help patients distinguish between certain colors, but these lenses don’t provide normal color vision and can distort objects. People with severe color vision problems can sometimes see differences between colors better when there is less glare and brightness, so glasses or contacts that reduce glare may be helpful. For the most part, those with color-blindness usually learn to look for cues like brightness or location to discern meaning where necessary. Early identification and support are usually the best ways to minimize any long term effects.
If you have any questions about the various conditions of the eye, or would like to schedule an eye exam, please contact Georgia Eye Physicians and Surgeons today to make an appointment. Be sure to follow us on Facebook, Twitter, and Google+ for more tips for healthy eyes.