Analysis of Galvanic Nystagmus in Patients with Ménière's Disease by Video-oculography

Galvanic nystagmus (GN) has been studied with regard to equilibrium. However, the nystagums-provoking mechanism has not been clarified. In this study, we considered Meniere's disease (MD) to be a unilateral vestibular disorder model, and analyzed GN recorded in MD by video-oculography. The subjects were 10 patients with MD (38-60 years). The patients were divided into an acute group of 5 patients who had the last insult within 2 weeks and a chronic group of 5 patients who had the last insult more than 4 weeks before. Stimulation of the cathode using direct current at 1, 2, or 3 mA for 30 sec was alternately performed on the affected and healthy sides in the acute and healthy subjects as controls using the mean frequency of nystagums and slow phase velocity. The mean frequency of nystagmus caused by stimulation at 2 MA on the affected side was significantly lower in the acute group (0.453±0.354 Hz) than in the control group (1.088±0.437 Hz) (P