抄録
Congenital nystagmus has been relatively easily diagnosed by using optokinetic nystagmus test because of its characteristic reactions, such as lack of optokinetic nystagmus, so-called “inversive reactions (bilateral, unilateral, and partial)”, or ataxic reaction. These characteristic reactions have long been believed to be seen only in patients with congenital nystagmus. However, recently we experienced an ataxic pattern of optokinetic nystagmus in acquired diseases which is quite similar to the ataxic pattern of optokinetic nystagmus in congenital nystagmus.
This fact has brought confusion in diagnosing congenital nystagmus, but at the same time, this might be a clue to elucidate the unknown pathophysiological mechanism of congenital nystagmus. In this paper we report 8 cases of acquired diseases which manifested ataxic reaction in optokinetic nystagmus test.
