Also known as cyanopia and blue vision. The term cyanopsia comes from the Greek words kuaneos (blue) and opsis (seeing). It is used to denote a *chromatopsia (i.e. a temporary aberration of colour vision) in which whites are seen as blue or bluish, and yellows as less intense. As the opposite condition (known as *xanthopsia or yellow vision) is sometimes caused by cataract of the lens, it is understandable that cyanopsia can occur as a temporary side effect after cataract extraction. Cyanopsia tends to be classified as an * entoptic phenomenon. The term is used in opposition to the terms *chloropsia (green vision), * xanthopsia (yellow vision), *erythropsia (red vision), and * ianothiopsia (violet or purple vision).
References
Pinckers, A., Cruysberg, J.R.M., Liem, T.A. (1989). Chromatopsia. Documenta Ophthalmologica, 72, 385-390.
Dictionary of Hallucinations. J.D. Blom. 2010.