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CURVA DE CRESCIMENTO DAS EMISSÕES OTOACÚSTICAS PRODUTO DE DISTORÇÃO EM NEONATOS
REV ASSOC MED B RAS 2014; 60(6):591-598 597
parado com os outros paradigmas (P1 e P2), e os valores
do slope do P geral forammaiores do que os obtidos nos P1
e P2. A média dos valores do slope no P geral foi de 10,05
na orelha direita e 8,85 na orelha esquerda.
CONCLUSÃO
Os limiares de surgimento foram em média 30 dB NPS
em 2.000 Hz e 35 dB NPS em 4.000 Hz, sendo, portanto,
os limiares de surgimento melhores na frequência de
2.000 Hz comparada a 4.000 Hz.
Não foi observada diferença nos valores de slope ob-
tidos nas curvas de crescimento das EOAPD; porém, as
curvas tinham inclinação mais íngreme nas intensidades
mais fracas (P1) e mais linear nas intensidades modera-
das (P2), sugerindo que a análise visual do gráico relete
a compressão coclear.
AGRADECIMENTOS
A Peter Bray e Lee VanMiddlesworth, da Otodynamic, que
colaboraram com conhecimento técnico todas as vezes que
foram consultados. À Prof. Erika Fukunaga, pela análise
estatística. AMirtes, Sonia e Daniel, secretários da pós-gra-
duação, pela ajuda constante e imprescindível. À bibliote-
cária Sadia Hussein Mustafá, pelos artigos conseguidos e
icha catolográica. À Faculdade de Ciências Médicas da
Santa Casa de São Paulo e à Irmandade da Santa Casa de
Misericórdia de São Paulo. À Capes, pela bolsa de estudos
concedida. Aos responsáveis pelos neonatos, que aceita-
ram o convite para participar deste estudo.
SUMMARY
Growth curve otoacoustic emissions distortion product
in neonates
Background: The recording of otoacoustic emissions
(OAE) enabled us to prove that the cochlea is able not
only to receive sounds but also to produce acoustic energy.
Through the use of distortion-product otoacoustic emis-
sion measurements, the growth of the response was seen
according to the intensity of the sound stimulus presen-
ted (growth curve).
Objective: to determine the thresholds for the emergen-
ce of distortion-product otoacoustic emissions (DPOAE)
on frequencies of 2000 and 4000 Hz with a stimulus
varying from 20 to 65dB SPL, and to establish the slope
values obtained in the growth curves.
Methods : 39 neonates aged 5 to 28 days without risk in-
dicators of hearing loss were studied. The DPOAE growth
curves were obtained on the frequencies from 2000 Hz
and 4000 Hz with a level of intensity ranging from 20 to
65dB SPL divided into two paradigms (20 to 40dB SPL
and 40-65dB SPL).
Results: there was a statistically signiicant difference in
the thresholds for the emergence of DPOAE depending
on the criteria used. The thresholds were on average higher
at 4000 Hz than 2000 Hz and the slope was higher on
average at 2000 Hz than 4000 Hz, although not statisti-
cally signiicant in either case.
Conclusion: the thresholds were on average 30dB SPL at
2000Hz and 35dB SPL at 4000Hz. The slope values varied
between 3 and 4 on average, reaching 15 in some cases.
Keywords: spontaneous otoacoustic emissions, hearing
tests, hearing, newborn.
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