Color Blindness - A Deficiency in Color Vision

Introduction

Color blindness is a condition that usually occurs right from birth or can be acquired in later life. Ideally, an eye comprises several layers like the cornea, sclera, lens, iris, retina, etc. The retina comprises two types of cells, cones, and rods. The rods work and detect dark and light environments. Rods do not perform any function regarding color vision. Rods are mostly concentrated in dark vision (vision in dark space). At the same time, cones are essential in detecting the colors in the environment.

Three types of cone cells are present in the retina and are involved in detecting red, blue, and green colors. If any of the color cones are not present, say if red cones are not present, that particular individual will not be able to view red colors in the environment. The condition is considered severe if all three color cones are absent and that person cannot detect colors other than black and white or view objects in the shades of gray from the environment.

Color blindness is a common inherited condition that affects both males predominantly, but females can also acquire it. It is X-linked hence, can be passed on by the mother who is a carrier to her son as males have only one X chromosome. However, if the father is color-blind and the mother is a carrier, the daughter can be color-blind too. It can be mild or severe. In milder conditions, the affected person may find it difficult to detect colors in dim light. Color blindness can be caused by various factors, most of which are various underlying medical conditions. This article will discuss the symptoms, causes, diagnosis, and treatment of color blindness.

What Are the Various Causes of Color Blindness?

Generally, the wavelength of red light is the longest, green being medium, and blue being the shortest. Therefore, when we view an object or a scene, light travels through the different layers of the eyes like the cornea, lens, vitreous humor (a gel-like substance), and finally reaches the retina. As discussed above, this retinal layer will contain the cones and rods. The cones contain the necessary chemicals for detecting the wavelength of the light reaching the retina. It sends appropriate information to the brain through the optic nerve and, thus, produces an image for vision. But if these cones do not present incorrect numbers, the color perception will reduce or diminish completely; thus, color blindness results. Various conditions can cause this condition, and they are as follows:

1. Genetics: Color blindness is most commonly inherited. It is predominantly seen in the male population rather than the female population. It can result in any degree of the condition, mild, moderate, or severe. The severity does not increase or decrease with age; it will remain the same. It affects both eyes. Blindness to red and green colors is more common, and blindness to blue and yellow is the least common. Blindness to all colors is a rare phenomenon.

2. Aging: Aging is another common cause of color blindness. But in older people, color blindness does not significantly affect their quality of life.

3. Medical Conditions: The presence of certain medical conditions will cause color blindness. Those medical conditions are as follows:

• Alzheimer’s disease.

• Multiple sclerosis.

• Diabetes.

• Glaucoma.

• Parkinson’s disease.

• Leukemia.

• Alcoholism.

• Macular degeneration.

These conditions affect one eye more commonly than the other. It resolves or gets better if the underlying medical conditions are treated appropriately.

• Medications: Certain medications are taken to treat medical conditions like high blood pressure, nervous conditions, psychological issues, erectile dysfunctions, autoimmune diseases, etc., and are bound to reduce the perception of cones to produce colored vision. Hydroxychloroquine is a common drug to cause color blindness.

• Exposure to Chemicals: Exposure to carbon disulfide and certain types of fertilizers in the workplace more commonly will cause color blindness.

What Are the Signs and Symptoms of Color Blindness?

• Some people may have inherited color blindness, and they will never know they are suffering from color blindness since they never got to see that particular color.

• In the case of people who got in the later stages of life will notice signs like an inability to differentiate the shades of colors like red, green, blue, yellow, etc.

How to Diagnose Color Blindness Condition?

It has to be properly diagnosed by a doctor. Once the patient discovers some issue with viewing colored images or identifying the colors, consultation with an ophthalmologist and a few tests have to be done. One such test involves a chart of different colors, and certain numbers and shapes will be embedded. If the patient finds it hard to find the numbers and shapes, it is confirmed that the patient is suffering from color blindness.

How to Manage Color Blindness Condition?

As such, there is no cure for inherited color blindness. Instead, one has to learn to live with it. A few of the suggestions that can be followed are to memorize the order of colors, especially in traffic lights. With the help of someone with good color vision, dresses can be arranged in a particular color order so that the process becomes easier in day-to-day life. Several technical applications are coming into the market to help color blindness-affected individuals sort colors.

If color blindness is acquired later in life due to some medication, chemical exposure, or medical conditions, it can be treated to a greater extent. It can be cured by stopping the medications causing it, reducing the chemical exposure by wearing appropriate protective eyewear, and treating the underlying medical condition appropriately.

Conclusion

Color blindness may affect the quality of life if acquired in later stages as they would already have the fruitful experiences of the colors that are blinded now. Treating the conditions at the right time can help cure them to a greater extent.