Severe progressive sensorineural hearing loss improved after removal of large jugular foramen schwannoma.
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 30-100dB 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 60-90dB 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.
Department of Otolaryngology, Head and Neck Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka, Tokyo, Japan. o-ishi@mub.biglobe.ne.jp
Naoki
N
Oishi
Naoyuki
N
Kohno
Yoshiaki
Y
Shiokawa
D000328:Adult; D001309:Auditory Threshold / Q000502:physiology; D003399:Craniotomy / Q000379:methods; D018450:Disease Progression; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D006320:Hearing Tests; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009361:Neoplasm Invasiveness; D009442:Neurilemmoma / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology; D010039:Otorhinolaryngologic Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D011183:Postoperative Complications / Q000175:diagnosis* / Q000503:physiopathology; D019292:Skull Base Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery*