[Pisa syndrome with laterocollis associated with bilateral chronic subdural hematomas: a case report with reference to peripheral vestibular hypofunction].

An 88-year-old woman with a history of two prior episodes of vertigo developed a mild leftward head tilt approximately four months after initiating pregabalin for severe tingling in the distal extremities. Two months later (day 1), she sustained a head injury without loss of consciousness. On day 22, she acutely developed leftward lateral flexion of the head while standing. Her gait progressively deteriorated, and she presented to our clinic on day 38. Neurological examination revealed mild disturbance of consciousness and marked leftward tilt of the head and trunk. Cranial MRI demonstrated bilateral chronic subdural hematomas without intra-axial lesions, including in the brainstem or cerebellum. Following surgical evacuation, the abnormal posture of the head and trunk resolved promptly. A horizontal, direction-fixed, right-beating nystagmus was observed, suggesting left-sided vestibular hypofunction. Subtle postural imbalance due to vestibular hypofunction and adverse effects of pregabalin may have been decompensated by the subdural hematomas, resulting in the pronounced cervical and truncal tilt.