title: Suppression effect of otoacoustic emissions in term and preterm infants.
abstract: OBJECTIVE
  This research aims at verifying the occurrence and magnitude of suppression effect of otoacoustic emissions evoked by transient stimulus in term and preterm infants, setting a benchmark for clinical use.
  
  
  METHODS
  The study sample consisted of 40 infants, with a rage of age from five days to four months, without any risk indicators for hearing loss and otoacoustic emissions present at birth: the 20 term and 20 preterm infants spent more than five days in the Neonatal Intensive Care Unit. Linear click was presented at 65 dB Sound Pressure Level, in blocks of 15 seconds without noise, and with contralateral noise at 60 dB Sound Pressure Level. The reduced response in the presence of noise indicates positive suppression effect. Mean values of suppression were established and the comparison between the groups was analyzed statistically.
  
  
  RESULTS
  Suppression occurred in 100% of the children and did not vary as a function of ear side and between the groups.
  
  
  CONCLUSIONS
  All children presented suppression regardless of the group. The average suppression obtained on the total population was 0.85 dB. The minimum recommended criterion for clinical use was a reduction of 0.20 dB in the overall response.
authors: Universidade Federal de São Paulo - UNIFESP - São Paulo (SP), Brasil.
authors: Natália Oliveira de
authors: NO
authors: Jesus
authors: Universidade Federal de São Paulo - UNIFESP - São Paulo (SP), Brasil.
authors: Rosanna Giaffredo
authors: RG
authors: Angrisani
authors: Universidade Federal de São Paulo - UNIFESP - São Paulo (SP), Brasil.
authors: Elaine Colombo
authors: EC
authors: Maruta
authors: Universidade Federal de São Paulo - UNIFESP - São Paulo (SP), Brasil.
authors: Marisa Frasson de
authors: MF
authors: Azevedo
mesh_terms: D000161:Acoustic Stimulation; D001309:Auditory Threshold / Q000502:physiology; D003430:Cross-Sectional Studies; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*