Definition: Achromatopsia (ACHM) is the inability to see color. Achromatopsia is often associated with vision problems such as amblyopia, nystagmus, light sensitivity, and very poor vision. It is an extremely rare hereditary vision disorder, affecting about 1 person in 33,000 in the United States.
Achromatopsia can be divided into two primary forms: complete achromatopsia and incomplete achromatopsia.
- Complete achromatopsia - People affected have no real understanding of the concept of color. The color red might be perceived as dark gray, or the color yellow may be perceived as light gray. Individuals with this condition see the world much like a black and white photograph, with various shades of gray.
- Incomplete achromatopsia - Although individuals have profound color impairment, they do have a small residual amount of color vision. Visual acuity is also slightly better due to the presence of some functioning cone cells in the retina.
Achromatopsia is classified as a recessive inherited condition, requiring both parents to contribute the gene in order for the condition to occur.
Also Known As: rod monochromatism
