Abstract
Contrary to the characterisitc slow growing of the tumor the authors report an acoustic neuroma with unusually rapid growth.
The 41-year-old male was first seen at the Jikei University Hospital with a complaint of left hearing defect of one month's duration.
Otoneurological examination showed left sensorineural hearing loss at lower frequency range, horizontal nystagmus and readily induced OKP.
ETT showed slight saccadic patterns and caloric test left canal paresis.
Radiological examination of the temporal bone revealed an obscure left internal auditory canal.
Within 3 months of the initial visit the patient became ataxic in gait associated with further aggravation in hearing.
Gaze nystagmus and OKP and ETT findings together with the above results were suggestive of central nervous system invasion of the tumor.
The dimension of the tumor had been confirmed by CT scan prior to surgical intervention. Exposure of the internal auditory canal revealed a large acoustic tumor with cystic changes involving the V, VIII, IX, X and XI cranial nerves.
