ABSTRACT
OBJECTIVE: To monitor the effect of mastoid drilling on the non-operated ear distortion product otoacoustic emissions. MATERIALS AND METHODS: Distortion product otoacoustic emissions (DPOAEs) were measured at frequencies of f 2=2, 3, 4 and 5 kHz, and a frequency ratio f 1 /f 2=1.22. DPOAEs were measured in 49 cases, pre and post-operatively who underwent mastoid drilling procedures, compared with each other and with 49 controls who underwent myringoplasty and myringotomy procedures. RESULTS: Amplitudes of DPOAEs decreased significantly in those who underwent mastoidectomies over all the measured frequencies in the immediate post-operative period but had recovered by the seventh post operative day. CONCLUSION: Drill induced noise can cause temporary decrease in the DPOAEs postoperatively and hence temporary hearing loss for a period of one week.
