Transmission of bone-conducted sound in the human skull measured by cochlear vibrations.
Journal article, 2008
One limitation with the Bone Anchored Hearing Aid (Baha) is too poor amplification for patients with moderate to severe sensorineural hearing losses. Therefore, we investigated if bone conducted (BC) sound transmission improves when the stimulation approaches the cochlea. Also the influence from the squamosal suture on BC sound transmission was investigated. Both sides of the heads on seven human cadavers were used and vibrational stimulation was applied at eight positions on each side with a frequency range of 0.1-10 kHz. A laser Doppler vibrometer was used to measure the resulting velocity of the cochlear promontory. It was found that the velocity of the promontory increases as the stimulation position approaches the cochlea; this was especially apparent at distances within 2.5 cm from the ear canal opening and when the stimulation position was in the opened mastoid. At frequencies above 500 Hz there was on average 10 to 20 dB greater vibrational response at the cochlea when the stimulation was close to the cochlea compared with the normal Baha position. Moreover, even if there were general indications of attenuation of BC sound when passing the squamosal suture, an effect from the suture could not be conclusively determined.
Humans
Cochlea
80 and over
Vibration
physiology
physiology
Regression Analysis
Cranial Sutures
Cadaver
Middle Aged
physiology
Acoustic Impedance Tests
Aged
Male
Aged
Bone Conduction
Female
Skull
Author
Måns Eeg-Olofsson
University of Gothenburg
Stefan Stenfelt
Chalmers, Signals and Systems, Signal Processing and Biomedical Engineering
Anders Tjellström
University of Gothenburg
Gösta Granström
University of Gothenburg
International Journal of Audiology
1499-2027 (ISSN) 1708-8186 (eISSN)
Vol. 47 12 761-9Subject Categories
Otorhinolaryngology
DOI
10.1080/14992020802311216
PubMed
19085400