Mohsen Rajati - Sinus and Surgical Endoscopic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Ali Ghanbari - Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.
Razieh yusefi - Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.
Sadegh Jafarzadeh - Department of Audiology, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran.
Navid Nourizadeh - Sinus and Surgical Endoscopic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Mohammad Reza Sharifian - Sinus and Surgical Endoscopic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
Imaneh Roshanzamir - Sinus and Surgical Endoscopic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

Introduction:The aim of this study was to investigate hearing outcome of stapes surgery, considering the post-operative air and bone conduction (AC&BC) changes, in a frequency specific approach.Materials and Methods:This was a retrospective cohort study. A total of ۲۴۵ ears (۲۳۱ patients), who underwent Stapedotomy at our tertiary referral center in a period of ۵ years were enrolled in the study. Pure tone audiometry (PTA) was evaluated preoperatively and one month postoperatively. AC, BC, and Air-bone gap (ABG) were documented. Moreover, one-year post-op PTA was also recorded for more than a quarter of the cases.Results:Overall, significant improvements were observed in AC thresholds with a mean AC gain of ۲۰.۴۴±۱۳.۶۴ dB. At higher frequencies the results were poorer (AC gain of ۲۷ dB at ۲۵۰ Hz vs ۷ dB at ۸۰۰۰ Hz). ABG significantly improved at all frequencies after one month. BC thresholds were typically better after surgery. However, there appears to be a worsening trend in BC thresholds at frequencies higher than ۲۰۰۰ Hz. In ۶۸ patients with ۱-year follow-up, BC thresholds were slightly worse (but not statistically significant) at most frequencies, in comparison to the one-month results.Conclusions:Stapes surgery significantly improves air and bone conduction hearing, particularly at lower frequencies. Nonetheless, there exists a potential for sensorineural hearing loss (SNHL) at high frequencies. However, the changes are insignificant and not within the speech frequencies. Therefore, patients are typically satisfied with the hearing outcome of the surgery.

Air conduction, Bone Conduction, frequency-specific, Hearing, Stapedotomy