Assessment of bone conduction prosthesis in situ.
Conventional and bone anchored bone conduction hearing aids can be tested with skull simulating devices and the individual adjustment rely on time consuming psychoacoustic audiometry in free-field which can be quite demanding for the patient. A method is presented in which the hearing aid induced skull vibrations are collected with an acceleromotor and recorded on a digital audio tape. The recordings are analysed with Fast Fourier 'Transformation (FFT) by using a signal processor. The free-field test signal can be either narrow-band or white noise. Changes in frequency characteristics can be easily monitored with white noise as signal, harmonic distortion and dynamic response can be analysed reliably by using pure tones. The inter-individual comparisons can be made when calibration is based on skull vibrations at the individual bone-conduction hearing thresholds. Two case reports are presented and discussed.
Laitakari
K
K
University of Oulu, Department of Otolaryngology, Finland.
Löppönen
H
H
D000328:Adult; D001299:Audiometry; D001844:Bone Conduction; D006310:Hearing Aids; D006801:Humans; D008297:Male; D008875:Middle Aged; D016348:Osseointegration; D012815:Signal Processing, Computer-Assisted