Digital spectral analysis of the drill-bone acoustic interface during temporal bone dissection: a qualitative cadaveric pilot study.
OBJECTIVE
To qualitatively assess the different acoustic signatures of an otologic drill burr-bone interface during temporal bone dissection on full thickness calvarial and thin tegmen bone.


BACKGROUND
An appreciable change in the sound generated by drilling occurs with progressive thinning of the bone during temporal bone dissection. To date, descriptions of this phenomenon are limited to a handful of subjective characterizations. Using digital power spectral analysis, interpretation of complex functions of time such as acoustic signals can be interpreted.


METHODS
Acoustic data recorded from five cadaveric temporal bone dissections were studied using digital spectral analysis.


RESULTS
The energy bandwidth concentration was between 5.0 and 7.9 kHz for full thickness bone using the cutting burr. Thin tegmen bone bandwidth concentration was lower, between 3.7 and 7.4 kHz and 3.9 and 6.0 kHz, using cutting and diamond burrs, respectively. Harmonic frequencies for thin tegmen bone-burr signals were 630 Hz.


CONCLUSIONS
There is a consistent, reproducible qualitative difference in the spectral domain of the acoustic signature from the drill burr-bone interface between thick calvarial bone and thin tegmen bone caused by a higher harmonic peak interval and lower energy bandwidth concentration in the thinned tegmen bone-burr interface signal thus concentrating the acoustic signal within a more optimal frequency range for human perception. These results allow for a better understanding of the perceived change in sound with progressive thinning of bone with drilling. In addition, these data may allow the development of more realistic acoustic interfaces in virtual reality temporal bone dissection simulators.
Shine
Neville Patrick
NP
South Infirmary Victoria Hospital, Cork, Republic of Ireland. shiner1@eircom.net
O'Sullivan
Peter G
PG
Connell
Joseph
J
Rulikowski
Pawel
P
Barrett
John
J
D000162:Acoustics; D002102:Cadaver; D005583:Fourier Analysis; D006801:Humans; D009622:Noise; D010865:Pilot Projects; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013701:Temporal Bone / Q000502:physiology* / Q000601:surgery*