1993 Volume 52 Issue 3 Pages 374-380
Positional nystagmus of the direction changing type, especially nystagmus towards the side of the upper ear in the lateral head position, is considered to appear in patients with disorders of the central nervous system. However, it might also occur in patients with peripheral vestibular disturbances.
The pathogenesis of nystagmus directed towards the upper ear side remains obscure because controversial results have been reported in several papers.
This paper discribes two patients with positional nystagmus directed towards the upper ear side, which was provoked after a short latency in both lateral head positions and disppeared within a few days. In both patients neurological and neurootological examinations indicated the presence of peripheral vestibular disorders.
A fragment of statoconia adhering temporarily to the cupula of the lateral semicircular canal might be the cause of the nystagmus in our two patients.
