Severe progressive sensorineural hearing loss improved after removal of large jugular foramen schwannoma

Abstract

We report a very rare case of hearing improvement after removal of the intracranial part of a jugular foramen schwannoma (JFS) presenting with chronic and severe progressive sensorineural hearing loss (SNHL). The patient presented with progressive hearing impairment in his right ear, lasting 2 years. The patient's pure tone audiogram revealed severe SNHL. His speech discrimination score (SDS) was 0%. Auditory-evoked brain responses (ABRs) comprised only I waves following 30–100 dB stimulation, although distortion-product otoacoustic emissions (DPOAEs) had good responses. These test results indicated that his hearing impairment was retrocochlear SNHL. Magnetic resonance imaging revealed within the right jugular foramen a large intracranial–extracranial tumor that compressed the brainstem. The intracranial part of the tumor was resected through retrosigmoidal craniotomy, and the tumor was pathologically diagnosed as a schwannoma. Several months after the operation, the patient's auditory thresholds improved to a level consistent with mild SNHL, ABR V waves emerged following 60–90 dB stimulation, and SDS improved significantly to 95%. This case demonstrates that hearing improvement can be achieved after surgery for JFS presenting with severe and chronic progressive SNHL, and that good DPOAE responses and the presence of ABR I waves may be predictors of postoperative hearing recovery in JFS.