title: Assessment of nasal-noise masking audiometry as a diagnostic test for patulous Eustachian tube.
abstract: OBJECTIVE
  The primary objective is to assess the validity of nasal-noise masking audiometry (NNMA) as a clinical diagnostic tool in our patient population.
  
  
  METHODS
  Retrospective case review.
  
  
  METHODS
  Tertiary ambulatory referral center.
  
  
  METHODS
  Patients with patulous Eustachian tube (PET) were identified from referrals to our Eustachian tube disorders clinic primarily with symptoms including autophony, aural fullness, and hearing their own breathing. The healthy subjects had no history of ear disease.
  
  
  METHODS
  NNMA was measured in 20 ears of 10 healthy subjects as well as in 42 ears of 21 patients with suspected PET.
  
  
  METHODS
  NNMA mean auditory thresholds were measured at frequencies ranging from 250 to 8,000 Hz.
  
  
  RESULTS
  When stratified as definitive or probable PET based on observed tympanic membrane movement with breathing, both Definitive and Probable PET groups had significantly higher NNMA mean auditory thresholds compared to Normal ears at 250 Hz (p = 0.001, p = 0.003), 1,000 Hz (p = 0.019, p = 0.001), and 6,000 Hz (p = 0.4, p = 0.001). When stratified based on symptoms on the day of testing, both Symptomatic Ears and Non-Symptomatic Ears had significantly higher mean auditory thresholds compared to Normal ears at 250 Hz (p = 0.001, p = 0.015) and at 1,000 Hz (p = 0.002, p = 0.004).
  
  
  CONCLUSIONS
  Our results demonstrate a larger masking effect in patients with PET compared to normal subjects in the low-frequency region. In clinical practice, the relatively small effect and the wide variability of results between patients have made this test be of little value clinically in our patient population.
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Justin
authors.initials: J
authors.lastname: Paradis
authors.forename: Manohar
authors.initials: M
authors.lastname: Bance
mesh_terms: D000328:Adult; D001299:Audiometry / Q000379:methods*; D001309:Auditory Threshold / Q000502:physiology*; D004427:Ear Diseases / Q000175:diagnosis* / Q000503:physiopathology; D005064:Eustachian Tube / Q000503:physiopathology*; D005260:Female; D006309:Hearing / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009622:Noise; D012189:Retrospective Studies