Achados timpanométricos em neonatos com emissões otoacústicas presentes: medidas e interpretações

Abstract

Tympanomet ry is used in evaluating middle ear functional conditions. Before six months of age its results may be misleading. High frequency studies aim to provide more valid procedures. Aim: To describe and discuss tympanometric measurements and the interpretation in normal hearing neonates at 226, 678 and 1000Hz. Method: 110 neonates that were analyzed had normal otoacoustic emissions and no risk for hearing impairment. The age range was 6 to 30 days. Curves were obtained using the GSI-33-II, at the "Divisão de Educação e Reabilitação dos Distúrbios da Comunicação", São Paulo, in 2004. Study design: Clinical prospective. Results: There was a balance between single and double peak curves at 226Hz. Most of the curves were asymmetric at 678Hz, and single-peaked at 1000Hz. quantitative measurements showed a significant gender difference in the Equivalent Ear Canal Volume at 226Hz and on the Peak Compensated Static Acoustic Admittance at 1000Hz. The English protocol showed that almost 100% of ears were normal at 678 and 1000Hz. Conclusion: 1000Hz yielded superior results for characterizing normality. The English protocol was efficient to reduce the variability of tympanometric measurements. Data from this study may be used as a guide for diagnosis using tympanometry in neonates.

Medidas imitanciométricas em crianças com ausência de emissões otoacústicas

“…20 If we consider a purely neonatal age range, the rate of Double peak tympanograms increases considerably (52.3%). 5 In the group of infants without TEOAEs, there was a higher rate of tympanogram alterations as presented on Table 5. We noticed that in 48.5% of altered and normal tympanograms, only 3% had a Double peak curve.…”

“…Studies with the 1000Hz probe in neonates proved to be efficient in detecting middle ear alterations. [3][4][5] The 226Hz probe tone has been suggested in the literature as the frequency of choice to assess infants up to four months of age, because such probe would be less affected by maturity differences and also because tympanometry patterns are better interpreted in this frequency when compared to the higher frequencies. 6,7 However, in the literature, papers stress the need to be careful in carrying out this test in infants below seven months of age, because they may present a type A tympanometry curve, even when there is fluid in the middle ear.…”

Simetria das medidas timpanométricas e as respostas das emissões otoacústicas transientes em neonatos

“…It is therefore necessary to also apply a 1000-Hz probe tone to acquire more reliable results 16,17 . Acoustic immittance using a 1000-Hz probe tone produces better results than using 226-and 678-Hz probe tones 1 .…”

“…Liliane Aparecida Fagundes Silva (1) , Kilza de Arruda Lyra e Silva (1) , Seisse Gabriela Gandolfi Sanches (1) , Renata Mota Mamede de Carvallo (1) (1) Faculdade de Medicina da Universidade de São Paulo, FMUSP, São Paulo, SP, Brasil.…”

“…For this reason, methods for the early evaluation of auditory system integrity are needed [1][2][3][4] .…”