We studied the effects of gender and ear asymmetry of infants in transient evoked otoacoustic emission (TEOAE), including signal-to-noise ratios (SNR) and emission reproducibility, using otoacoustic emission for screening in a well-born nursery. TEOAE was analyzed in 253 healthy full-term newborns, i. e., 138 males and 115 females. Results indicated significant gender and ear effects on SNR, response, and whole wave and band reproducibility. The right ear was found to have higher whole wave reproducibility, response, SNR, and band reproducibility than the left ear. Girls showed higher whole wave reproducibility, response, band reproducibility, and SNR than boys, as we discuss in light of previous results.
We studied the efficacy of a digital hearing aid with an adaptive beamformer (senso Diva® SD-9M). The hearing aid was fitted using an SP3 fitting device. The testing protocol included speech recognition tests using 67S word lists presented at 60dBSPL (0° azimuth) in the presence of 70dBSPL speech noise (at 90° or 180° azimuth). Speech recognition scores were measured while subjects wore an SD-9M with 4 fitting algorithm or noise azimuth conditions (beamformer on/90°; beamformer on/180°; beamformer off/90°; and music mode/90°), Results showed that speech recognition in noise improved with the beamformer.
A-to-G mutation at nucleotide positions 3243 and 1555 of mitochondrial DNA may cause sensorineural hearing loss. We studied such mutation in patients with bilateral sensorineural hearing loss of unknown etiology, finding 3 cases of A3243G mutation and 1 of A1555G mutation in 46 cases. It 3243 mutation is reported to be associated with diabetes mellitus and maternally inherited sensorineural hearing loss, and our study showed 3 cased of A3243G mutation in 8 cases having both maternally inherited hearing loss and diabetes mellitus. A case of A1555G mutation occurred in 1 case of maternally inherited hearing loss. Hearing loss related to A3243G mutation was characterized by late onset in adulthood and slow progression. That in A1555G mutation was characterized by comparatively rapid hearing loss.