title: [Normal parameters of ear acoustic emissions in neonates].
abstract: BACKGROUND
  The ear acoustic emissions (EAE) are produced from pure low intensity tones coming from the cochlea in response to a stimulus. Hypocusia in the neonate may be detected by universal hearing screening programs using EAE that have a sensitivity of 91% and specificity of 85%.
  
  
  OBJECTIVE
  To define the normal limits we measured the EAE in a group of healthy newborns and calculated the media and standard deviation (SD).
  
  
  METHODS
  We enrolled 280 healthy neonates, previous external ear evaluation for permeability and we measured the EAE at 7 to 30 days of life at 2000, 2500, 3187, 4000, 5062 y 6375 Hz, using a 55-65 dB stimulus for each frequency band.
  
  
  RESULTS
  In each frequency band evaluated we calculated the media: 10.76, 9.16, 9.46, 7.89, 4.83, 2 dB SPL, and minus two SD: 0.54, -0.33, 0.06, -2.04, -4.37, -7.43 dB SPL, that we considered the lower limit of normality for both ears in each frequency band tested. There were no significant differences between measurements in both ears (p>0.05).
  
  
  CONCLUSIONS
  The EAE measurement is an easy, and low cost test that can be used to make the universal hearing screening accessible. These results support the normal levels of EAE and the Corti organ function in healthy newborns.
authors.affiliation: Departamento de Pediatría, Hospital Regional de Especialidades 23, Instituto Mexicano del Seguro Social, Monterrey, Nuevo León, Mexico. richdzher@hotmail.com
authors.forename: Ricardo Jorge
authors.initials: RJ
authors.lastname: Hernández-Herrera
authors.forename: Luz María
authors.initials: LM
authors.lastname: Hernández-Aguirre
authors.forename: Norma
authors.initials: N
authors.lastname: Castillo-Martínez
authors.forename: Natalia
authors.initials: N
authors.lastname: de la Rosa-Mireles
authors.forename: Jesús
authors.initials: J
authors.lastname: Martínez-Elizondo
authors.forename: Roberto
authors.initials: R
authors.lastname: Flores-Santos
authors.forename: Miguel Eloy
authors.initials: ME
authors.lastname: Torcida-González
authors.forename: Rogelio
authors.initials: R
authors.lastname: Hernández-Núñez
mesh_terms: D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D012016:Reference Values