Blåsynsdefekter

Blåsynsdefekter, also known as blue color blindness or tritanomaly, is a rare form of color vision deficiency where an individual has difficulty distinguishing between blue and green, and also between yellow and red. It is not a complete absence of color vision, but rather a reduced sensitivity to blue light.

This condition is typically congenital, meaning it is present from birth, and is usually inherited in an autosomal recessive pattern, although autosomal dominant inheritance has also been observed. It is caused by a genetic mutation affecting the cone cells in the retina, specifically those responsible for detecting blue wavelengths of light. In tritanomaly, the cones are present but function abnormally. In tritanopia, the cones are absent.

Individuals with blåsynsdefekter may perceive blues as greenish or grayish, and yellows as pinkish or reddish. This can affect their ability to discern traffic lights, distinguish between different colored objects, and appreciate the full spectrum of colors. The severity can vary, with some individuals experiencing mild difficulties while others have more significant challenges.

Diagnosis is usually made through specialized color vision tests, such as the Ishihara plates or the Farnsworth-Munsell 100-hue test. There is currently no cure for congenital blåsynsdefekter, but in some cases, specialized filters or contact lenses can assist with color discrimination. Acquired forms of blue color vision deficiency can occur due to certain medical conditions or medications, and addressing the underlying cause may improve vision.