Benutzerspezifische Werkzeuge

Measuring System for Evaluating Drilling Induced Noise

For surgical interferences at the human head using medical drilling tools it has been concern that the induced noise, transmitted via bone conduction, could damage the cochlea. For evaluating the drilling induced noise, we develop an acoustical measuring system which is (1) capable to determine an equivalent sound pressure level, and (2) applicable to the day-to-day operations of a clinic.


It is already known, that sound is not only transmitted by air conduction to the cochlea via the outer and middle ear, respectively. The perception of sound is also done by bone conduction, e.g. wave propagation in the cranium and/or effects of inertia of the ossicular chain of the middle ear. This can impressively demonstrated by pressing an oscillating tuning fork at someones head. This pathway of the perception of sound could be hazardous to the patient during operations at the cranium by using high speed drills. In an in vivo study, we measured equivalent sound pressure levels >120 dB(A). Therefore, it is necessary to regulate the noise exposure to keep intact the full or partial hearing of the patients.