[Auditory steady-state response in the auditory evaluation: clinical application].
BACKGROUND
the auditory steady state response (ASSR) is an electrophysiological procedure that evaluates, at the same time, the hearing thresholds of both ears at various frequencies. This procedure reduces the time of testing and enables the stimulation of levels close to 125dB HL, characterizing residual hearing.


OBJECTIVE
to verify the applicability of the ASSR to determine the hearing thresholds in different levels of sensorineural hearing loss.


METHODS
48 individuals aged 7-30 years, with different levels of hearing loss were assessed. The Pure tone Audiometry (PTA) and the ASSR were carried out in following carrier frequencies 0.5; 1; 2 and 4k Hz. The carrier frequencies in the ASSR were modulated in amplitude and frequency, with multiple dicotic stimulation for mild and moderate hearing loss. Simple stimulation was used to test the other hearing deficit levels.


RESULTS
there was a significant association (p<0.01) between the thresholds obtained in the PTA and in the ASSR for all of the tested frequencies, especially for the severe levels. However, for some patients, the hearing loss level was overestimated in the ASSR.


CONCLUSIONS
the ASSR can be used to estimate the PTA threshold; nevertheless, it should not be analyzed in an isolated way, but seen as a complementary procedure to the behavioral auditory assessment.
Duarte
Josilene Luciene
JL
Departamento de Fonoaudiologia, Faculdade de Odontologia de Bauru, Universidade de São Paulo. josileneduarte@uol.com.br
Alvarenga
Kátia de Freitas
Kde F
Garcia
Tatiana Manfrini
TM
Costa Filho
Orozimbo Alves
OA
Lins
Otávio G
OG
D000293:Adolescent; D000328:Adult; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold / Q000502:physiology*; D002648:Child; D004594:Electrophysiology; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D008297:Male; D013017:Sound Localization / Q000502:physiology*; D055815:Young Adult