Nystagmus: prevalence, classification, pathogenesis. (Literature review)
The article provides information on the prevalence of nystagmus in the Russian Federation and the world. However, the lack of standards for data collection and the very understanding of the definition of optical nystagmus is the reason for the variation in prevalence values in different sources. Additionally, the article presents various classifications of nystagmus. Currently, there are many different classifications, and the most commonly used examples are given. The classification of eye movement disorders and strabismus, adopted by the working group in 2001 (Classification of Eye Movement Abnormalities and Strabismus CEMAS), is used worldwide. In our country, the most popular was the classification proposed by E.S. Avetisov (2001). Various sources have suggested quite contradictory data on the nature of the onset and the mechanism of development of nystagmus. Recently, the issues related to the pathogenesis of nystagmus have been revised. The theories that existed at the end of the last century were not substantiated in modern works. The pathogenesis of optic nystagmus remains less studied due to its complexity and ambiguity. The investigations continue to find the relationship between the pathology of the central nervous system and functional disorders of visual functions. The question of the relationship between visual acuity and nystagmus remains unclear. Does a decrease in vision cause nystagmus? How do oscillatory movements in nystagmus affect visual functions? This article encompasses the main areas of this issue. However, despite a significant step in understanding the causes of the development of nystagmus, this pathology remains insufficiently studied. This prompts many researchers and practicing doctors to study its pathogenesis further