Abstract
Dix and Hallpike reported previously of a disease state in which vertigo occurs in association with a specific position of the head in space, and is accompanied with rotatory nystagmus of transient duration. These authors postulated that the condition is distinct from Meniere's and described it as “benign paroxys-mal positional nystagmus”(BPPN). The present author noticed similar attacks of BPPN occurring frequently during the course of Meniere's disease. The purpose of this paper is to give a brief account of these cases. Six cases of BPPN were seen during 1988. In all six cases, there first occurred a typical attack of Meniere's disease, accompanied with horizontal nystagmus andsmarked deviation for the stepping test. In 4 of the 6 cases, the rotatory nystagmus of BPPN was noted to occur as the Meniere's attack was subsiding. In the other two cases, after a period of clinical quitescence following an initial Meniere's attack, a second attack started with BPPN. The duration of the BPPN attacks ranged from 4 days to 4 months. The horizontal nystagmus of Meniere's disease and the rotatory nystagmus of BPPN generally were in opposite directions. There were no striking left-to-right differences in either audiograms or calorigrams. Gait tests performed during an episode of BPPN demonstrated forward and backward gait to deviate to the same direction in many instances. This was interpreted as indicating that probably, and mainly as a result of excitation of statoconia, there was a tendency to lateropulsion, but not to laterotorsion. During the course of BPPN there occasionally were transient reversals of the rotatory nystagmus direction with the same postion of the head. This phenomenon was arbitralily called reversed nystagmus of delayed onset. In 4 of the 6 cases, the patient's received hospital treatment. During the year of 1988, a total of 97 patients were admitted to the hospital with an attack of Meniere's disease. Thus it follows that of these, 4.1% went on to develop BPPN. BPPN is considered to be a condition occurring during Meniere's disease, a process which involves the entire inner ear, in which only the statoconia are in a state of excitement. Therefore, it should be regarded as a pathologic condition of the inner ear rather than an independent disease entity.
