Evaluation of bone-conducted sound during ear surgery: an in vivo pilot study

The impact of noise induced by drilling on hearing during ear operations has been discussed several times in the past. However, direct measurements of the equivalent sound pressure level in patients undergoing ear surgery have not previously been reported. This pilot study presents an easy-to-use method based on a calibrated accelerometer to determine the equivalent sound pressure level potentially applicable in the clinical routine. During seven monitored cochlear implant surgeries, the equivalent A-weighted sound pressure level L AF ranged from 111 to 126 dB(A) eqSPL at its maximum, whereas C-weighted peak levels L Cpeak showed peaks up to 140 dB(C) eqSPL . The recommended daily noise exposure limit was exceeded for three of the seven patients, suggesting the potential for drilling-induced temporal shifts in hearing threshold. Based on these findings, standardized noise monitoring is recommended as a quality assurance measure during otological surgery.