Hearing screenig using steady state evoked potentials with white noise stimuli

THESES

Hearing screenig using steady state evoked potentials with white noise stimuli (Abstract)^*. Dissertation. Recife 2010

Danielle Gomes Pinto^**

BACKGROUND: Early identification of hearing loss and early intervention are crucial to maximize the development of receptive and expressive language abilities and communicative experience. Therefore, the need for universal newborn hearing screening has been ratified by the Joint Committee on Infant Hearing. Objective physiological techniques which are not influenced by sleep or sedation, have to be applied to be able to provide adequate intervention before 6 months of age. Auditory steady-state potentials evoked by amplitude modulated noise or transient stimuli might be useful in providing rapid and objective tests of hearing during screening procedures.

OBJECTIVE: The aim of this study was to evaluate the use of auditory steady-state evoked potentials with white noise stimuli as a screening tool.

METHOD: This study was approved by the Human Research Ethics Committee. The population of the study was composed of 30 newborns. The equipment used in the study was the MASTER. The stimuli was white noise amplitude modulated between 80 and 110 Hz, the electrodes position were: FZ active, M1 reference and M2 ground. All stimuli were presented at 40 dBSPL to 70 dBSPL intensities. The ears were recorded simultaneously.

RESULTS: The data was inserted in Microsoft Excel 2002 for Windows program, were analyzed specificity, sensibility and likehood ratio. For the intensity of 50dBSPL considered as the point of pass-fail, the results for sensibility were 100%, specificity: 100% and LR+: ∞, which shows a near relation between ASSR screening and the gold standard assessment. There was a high fail index (10%), probably because were evaluated high risk children with risk factors for hearing loss (prematurity and low-weight), and the media of age was 28 days, its known that in this age, changes in ear canal-recorded sound levels across the assessment period can be observed, what may reflect differences in ear canal volume, canal resonance and middle eat mechanical properties.

CONCLUSION: This work showed that the use of auditory steady state with white noise in hearing screening is possible, and a alternative tool for hearing screening assessment. Clinical application of the ASSR procedure in the neonatal population will need to take into account developmental changes occurring in the first weeks of life. More studies have to be made to solidify these findings.

Key words: auditory, steady state, hearing screening, white noise.

*

Triagem auditiva por potencial evocado de estado estável com estimulo white noise (Resumo). Dissertação de Mestrado, Universidade Federal de Pernambuco, UFPE (Área: Neurociências). Orientador: Otávio Gomes Lins.

Publication Dates

• Publication in this collection
  24 June 2010
• Date of issue
  June 2010