Subacute Progression of Gait Disturbance and Consciousness Impairment Due to Communicating Hydrocephalus Associated With Vestibular Schwannoma.

Patients with vestibular schwannomas (VSs) present with vestibulocochlear nerve dysfunction such as vertigo and tinnitus. VSs occasionally develop communicating hydrocephalus as a complication, which is typically characterized by an insidious progression of symptoms. We report a case of an 84-year-old female patient with a VS who developed gait disturbance and consciousness impairment over a three-week period, ultimately resulting in an inability to walk and communicate. A thorough evaluation ruled out encephalitis and other differential diagnoses. Imaging studies demonstrated findings consistent with communicating hydrocephalus, and a tap test temporarily improved her consciousness disturbances. The patient underwent ventriculoperitoneal shunting and stereotactic radiosurgery (SRS), after which both consciousness and gait disturbances dramatically improved 10 days postoperatively. The subacute development of symptoms due to normal pressure hydrocephalus associated with VSs is rare. Furthermore, to the best of our knowledge, this is the first reported case of severe gait impairment and disturbance of consciousness progressing within a short period. This case highlights the importance of considering communicating hydrocephalus associated with VSs as a differential diagnosis, even in cases of subacute consciousness disturbance. We also discuss the pathophysiology of hydrocephalus in relation to cerebrospinal fluid (CSF) clearance into the extracranial space.