What is Tritanopia?
Tritanopia is a type of color vision deficiency that affects the perception of color. Individuals with tritanopia have a blue-yellow defect. A blue-yellow defect does not mean they can’t see yellow and blue, but they have difficulty differentiating shades of blue and green. While tritanopia affects color perception, it does not affect the clarity or sharpness of your vision. Tritanopia is more rare than a red-green deficiency and is estimated to affect 1% of the population.
- Individuals with tritanopia have a blue-yellow color defect.
- Tritanopia is congenital and affects both males and females.
- Tritanopia cannot be cured, but may be improved with specialty tinted glasses, aids, and apps.
Individuals with tritanopia are missing the S-cones, which are the type of cone sensitive to short-wavelengths of light. Tritanopia prevents one from being able to tell the difference between blue and green, purple and red, and yellow and pink. It also makes colors appear less bright. Blue–yellow color blindness can be a more serious deficiency because some individuals may also have red–green color blindness.
Tritanomaly is different from tritanopia in that those with Tritanomaly have difficulty distinguishing between green and blue, and red and yellow. Individuals with tritanomaly have defective S-cones caused by a gene mutation. When compared, those with tritanopia seem to have less difficulty performing routine tasks than those with red–green color deficiency.
Risk Factors for Tritanopia
Tritanopia is an autosomal dominant disorder of the visual system and is typically present at birth. It is a genetic mutation, but in contrast to other forms of color blindness, is not an x-linked recessive trait. It is equally found in both males and females. Tritanopia can be acquired with certain ocular conditions such as cataracts, diabetes, and macular degeneration. Other factors that have demonstrated an association with tritanopia are alcoholism, workers exposed to low concentrations of organic solvents, and traumatic brain injuries.
- Difficulty with shades of blue and green
- Difficulty distinguishing dark blue from black
- Increased light sensitivity (photophobia)
Doctors commonly use the Ishihara Color Test to diagnose Tritanopia. The Ishihara Color Test requires the patient to look at a series of dots. Individuals with normal vision will be able to see the dots, but the number will be invisible or difficult for those with Tritanopia.
The only treatment available for tritanopia is specially tinted glasses designed for color blindness. The glasses may be beneficial in viewing colors more accurately. Colorblind glasses contain optical materials designed to filter specific wavelengths of light. Visual aids or color vision apps may be helpful for day-to-day living.
There is not a cure for any type of color blindness, but gene therapy for color blindness is currently being researched and success has been demonstrated in monkeys.