Characterizing the auditory changes in tumor metastasis to the bilateral internal auditory canals.
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.
Sone
Michihiko
M
Department of Otorhinolaryngology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan. michsone@med.nagoya-u.ac.jp
Katayama
Naomi
N
Otake
Naohiro
N
Sato
Eisuke
E
Fujimoto
Yasushi
Y
Ito
Masafumi
M
Nakashima
Tsutomu
T
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*