Dizziness after an earthquake tilted the house.

Major earthquakes occasionally cause vertiginous attacks or persistent dizziness, which may be related to the effects of autonomic stress on equilibrium function and/or psychological factors. We present the case of a 73-year-old woman who suffered from persistent dizziness for 1 year, during which she lived in a house tilted by the great 2011 Tōhoku earthquake. An electronystagmogram demonstrated leftward horizontal and downbeat nystagmus in the sitting and supine positions with eyes closed. Caloric testing and cervical vestibular-evoked myogenic potentials showed normal responses in both ears. Posturography indicated no involvement of psychological factors or autonomic stress. After moving into a new apartment, both the dizziness and nystagmus completely disappeared within 10 weeks. We speculate that the gravity-related linear acceleration with vertical and horizontal components in the tilted house may have chronically stimulated the otoliths, inducing the symptoms and nystagmus via the velocity storage mechanism.