title: Characterizing the auditory changes in tumor metastasis to the bilateral internal auditory canals.
abstract: We report the changes in auditory function in a patient with tumor metastasis to the bilateral internal auditory canals (IAC). The hearing gradually deteriorated at frequencies below 1 kHz and above 4 kHz, with the auditory brainstem response (ABR) eventually becoming absent in both ears. However, distortion product otoacoustic emissions (DPOAE) were present at low frequencies, which suggests that the organ of Corti in its upper turn remained unaffected by tumor invasion. Metastatic tumors in the bilateral IAC have been reported to mimic neurofibromatosis type 2, and radiological differentiation from acoustic schwannoma is difficult. We characterize the hearing deterioration caused by metastasis of malignant tumors in the IAC.
authors: Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan. michsone@med.nagoya-u.ac.jp
authors: Michihiko
authors: M
authors: Sone
authors: Naomi
authors: N
authors: Katayama
authors: Naohiro
authors: N
authors: Otake
authors: Eisuke
authors: E
authors: Sato
authors: Yasushi
authors: Y
authors: Fujimoto
authors: Masafumi
authors: M
authors: Ito
authors: Tsutomu
authors: T
authors: Nakashima
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000230:Adenocarcinoma / Q000473:pathology; D003390:Cranial Nerve Neoplasms / Q000503:physiopathology* / Q000556:secondary; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005770:Gastrointestinal Neoplasms / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000503:physiopathology*; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*