[Normalcy parameters of spontaneous otoacoustic emissions]

In the present study we analyze the spontaneous otacoustic emissions (SOAEs) in a sample of 232 hearing-preserved ears. The examination was performed in people of the same gender aged 18 to 32 years (mean age 23.35) and always in the ear of the same side. We have found that the incidence of the SOAEs was 42.6% of the ears and 53.5% of the individuals, being modified by sex, age and audiometric threshold. Incidence in females was 58.62% and in males 26.72%. Mean age of the group presenting SOAEs was 22.68 years, while in the group without SOAEs was 23.85% years. The audiometric threshold in patients with SOAEs was lower (7.27 dB HL) that in those ears without SOAEs (8.17 db HL). Other parameters studied were the number of peaks, the intensity and the frequency of spontaneous otacoustic emissions. The number of peaks of the SOAEs varied from 1 to 12 (mean 3.1). Women showed higher number of peaks than men did. The intensity was ranged between 3 and 51 db SPL (mean 20.1 db SPL). The frequency spectrum presented a range from 488 to 6,103 hertzs, with a higher incidence (48.5%) in the frequency bands of 1,000 and 2,000 Hz. All these data were statistically significant.