title: Acoustic immittance in children without otoacoustic emissions.
abstract: Considering the hypothesis that middle ear changes can impair the recording of otoacoustic emissions, it is possible that absent otoacoustic emissions in infants could be associated with a light tympanometric change.
  
  
  OBJECTIVE
  To study the association between transient otoacoustic emissions and changes in acoustic immittance measurements with 226 Hz probe tone in neonates.
  
  
  METHODS
  Cross-sectional contemporary cohort study. 20 infants with no transient otoacoustic emissions (study group) and 101 infants with transient otoacoustic emissions (control group), with ages ranged from birth to eight months, were assessed. Infants were submitted to: admittance tympanometry; contralateral acoustic reflex threshold with stimulus of 0.5, 1, 2, 4 kHz and broad band noise; transient and distortion product otoacoustic emissions. The auditory brain response was used to study the threshold in neonates without transient otoacoustic emissions.
  
  
  RESULTS
  Significant statistical differences were observed between the groups (p < 0.005), characterized by reduction in tympanometric configuration and increase acoustic reflex thresholds in the study group. These data suggest the occurrence of middle ear mild impairment in infants without transient otoacoustic emissions associated with normal auditory brain response.
  
  
  CONCLUSIONS
  tympanometry associated with acoustic reflex adds accuracy to the diagnosis of middle ear abnormalities.
authors.affiliation: FM, Universidade de São Paulo, Brazil.
authors.forename: Ana Emilia
authors.initials: AE
authors.lastname: Linares
authors.forename: Renata Mota Mamede
authors.initials: RM
authors.lastname: Carvallo
mesh_terms: D000158:Acoustic Impedance Tests; D000161:Acoustic Stimulation; D001309:Auditory Threshold / Q000502:physiology*; D016022:Case-Control Studies; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D004432:Ear, Middle / Q000503:physiopathology*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D012016:Reference Values; D012022:Reflex, Acoustic / Q000502:physiology*