Dpoae20 teb

Audiological tests were performed in a standard anechoic chamber with a pure-tone audiometer (Interacoustics AD229b; Interacoustics A/S DK-5610 Assens, Denmark) at frequencies ranging from 250 to 8000 Hz. Using an acoustic emmittance measurement apparatus (Interacoustics AT235h; Interacoustics A/S DK-5610 Assens), auditory brainstem response (ABR) was recorded ipsilaterally in response to click stimuli presented at 100 dBnHL (Interacoustics Eclipse EP2; Interacoustics A/S DK-5610 Assens). Additionally, a distortion product otoacoustic emissions system (DPOAE; 2f1–f2; Interacoustics DPOAE20 + TEb; Interacoustics A/S DK-5610 Assens Denmark) was used, where f2/f1 = 1.22; the level for f1 was 65 dB SPL, and the level for f2 was 50 dB SPL (DP S/N: 5 dB SPL). Ear endoscopy, computed tomography (CT) scans, and magnetic resonance imaging (MRI) were used to exclude deafness caused by anatomical abnormalities of the middle and inner ear.

Audiological tests were performed in a standard anechoic chamber with a pure-tone audiometer (Interacoustics, AD229b, Manufactured by Interacoustics A/S DK-5610 Assens Denmark) at frequencies ranging from 250–8000 Hz. Using an acoustic emmittance measurement apparatus (Interacoustics, AT235 h, Manufactured by Interacoustics A/S DK-5610 Assens Denmark), ABR was recorded ipsilaterally in response to click stimuli presented at 90 dBnHL (ABR, Interacoustics, Eclipse EP2, Manufactured by Interacoustics A/S DK-5610 Assens Denmark), and DPOAE (2f1–f2) (Interacoustics, DPOAE20+TEb, Manufactured by Interacoustics A/S DK-5610 Assens Denmark, f2/f1 = 1.22; the level for f1 was 65 dB spl and the level for f2 was 50 dB spl. DP S/N: 5 dB SPL) was used. Ear endoscopy, CT scans, and MRI were used to exclude deafness caused by anatomical abnormalities of the middle and inner ear.