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Published on: February 10, 2023
Effect of drill-induced noise on hearing in non-operated ear
Seyyed Hamidreza Abtahi1, Alireza Fazel1, Mehrdad Rogha1
1Department of Otorhinolaryngology, Isfahan University of Medical Sciences, Isfahan, Iran.
Background:
The aim of this study was to evaluate the effect of drill-generated noise on hearing loss in non-operated ear and if any, was temporary or persistent.
Materials And Methods:
In this prospective clinical study, 23 patients who had undergone mastoidectomy and normal contralateral hearing were enrolled. Patients were evaluated preoperatively and postoperatively (1 and 7 days) following surgery using low and high-frequency pure tone audiometry (PTA) and low and high-frequency transient evoked and distortion product otoacoustic emission (DPOAE) testing.
Results:
Comparing preoperative and 1-day after surgery, PTA averages were significantly different at low frequencies, but no statistical significant differences were observed at 0.25 KHz and high-frequencies. Comparing 1-day after surgery and 7 days after surgery showed that, PTA averages at 0.5, 2 and 2 KHz were significantly different with no significant differences at the other average of thresholds in low and high frequencies; PTA average at 1 KHz was significantly different with, no significant differences at the other averages of thresholds in low and high frequencies. DPOAEs showed a significant difference preoperative and 1-day after surgery, 1-day and 7 days after, but DPOAEs were not significantly different. Transiently evoked otoacoustic emissions (TEOAEs) had a significant difference preoperative and 1-day after surgery, 1-day and 7 days after but when comparing preoperative and 7 days after surgery, TEOAEs were not significantly different.
Conclusions:
Drill-induced noise during ear surgery (mastoidectomy) can cause reversible changes in PTA, DPOAEs and TEOAEs in the non-operated ear.

