Vestibular investigations in Meniere's disease

151 patients with unilateral Meniere's disease were investigated with a vestibular test battery in the interval between vertigo attacks, and the results were compared with those obtained in a control group. In 73.5% of the patients a caloric response reduction of the afflicted ear was observed. The mean caloric response reduction was 34.3%; a major response reduction or a total absence of the caloric response of the afflicted ear was rare. A correlation was found between the amount of caloric response reduction and the duration of the disease. Spontaneous nystagmus was found in 47% of the cases (mean value 3 degrees/sec) and a mainly direction fixed positional nystagmus in 78% (mean value 4.0 degrees/sec). No correlation was found between the mean hearing loss and the magnitude of caloric response reduction on the day of investigation.