title: Auditory adaptation testing as a tool for investigating tinnitus origin: two patients with vestibular schwannoma.
abstract: To enhance the understanding of tinnitus origin by disseminating two case studies of vestibular schwannoma (VS) involving behavioural auditory adaptation testing (AAT).
  
  
  
  Retrospective case study.
  
  
  
  Two adults who presented with unilateral, non-pulsatile subjective tinnitus and bilateral normal-hearing sensitivity. At the initial evaluation, the otolaryngologic and audiologic findings were unremarkable, bilaterally. Upon retest, years later, VS was identified.
  
  
  
  At retest, the tinnitus disappeared in one patient and was slightly attenuated in the other patient. In the former, the results of AAT were positive for left retrocochlear pathology; in the latter, the results were negative for the left ear although a moderate degree of auditory adaptation was present despite bilateral normal-hearing sensitivity. Imaging revealed a small VS in both patients, confirmed surgically.
  
  
  
  Behavioural AAT in patients with tinnitus furnishes a useful tool for exploring tinnitus origin. Decrease or disappearance of tinnitus in patients with auditory adaptation suggests that the tinnitus generator is the cochlea or the cochlear nerve adjacent to the cochlea. Patients with unilateral tinnitus and bilateral, symmetric, normal-hearing thresholds, absent other audiovestibular symptoms, should be routinely monitored through otolaryngologic and audiologic re-evaluations. Tinnitus decrease or disappearance may constitute a red flag for retrocochlear pathology.
authors.affiliation: a Department of Speech-Language Pathology and Audiology , Hunter College, City University of New York , New York , NY , USA.|b AuD Program and PhD Program in Speech-Language-Hearing Sciences , Graduate Center, City University of New York , New York , NY , USA.|c Department of Otolaryngology-Head and Neck Surgery , New York Medical College , Valhalla , NY , USA , and.
authors.forename: Carol A
authors.initials: CA
authors.lastname: Silverman
authors.affiliation: b AuD Program and PhD Program in Speech-Language-Hearing Sciences , Graduate Center, City University of New York , New York , NY , USA.|d Department of Speech Communication Arts and Sciences , Brooklyn College, City University of New York , Brooklyn , NY , USA.
authors.forename: Shlomo
authors.initials: S
authors.lastname: Silman
authors.affiliation: d Department of Speech Communication Arts and Sciences , Brooklyn College, City University of New York , Brooklyn , NY , USA.
authors.forename: Michele B
authors.initials: MB
authors.lastname: Emmer
mesh_terms: D000223:Adaptation, Psychological; D001307:Auditory Perception; D001309:Auditory Threshold; D006309:Hearing; D006320:Hearing Tests; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology; D011237:Predictive Value of Tests; D013997:Time Factors; D014012:Tinnitus / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology
keywords: Behavioural measures; conditions/pathology/disorders; medical audiology; tinnitus