Comparison of Pre and Post-operative Hearing Results in Canal Wall Down Mastoidectomy with Type III Tympanoplasty

Abstract

This study was done to compare the pre and post-operative hearing results in patients undergoing canal wall down mastoidectomy with classical type III tympanoplasty using temporalis fascia alone. Patients of ≥5 years age with the diagnosis of Chronic otitis media (squamous) with conductive or mixed hearing loss, needing canal wall down mastoidectomy and with intact and mobile stapes suprastructure at surgery who underwent classical type III tympanoplasty were included in the study. The pre and post-operative PTA was performed and evaluated. The post-operative hearing was assessed in terms of average ABG and size of ABG closure. Mean pre and post-operative air bone gap in classical type III tympanoplasty were 37.8 dB and 29.8 dB respectively and these differences were statistically significant. The postoperative PTA-ABG ranged from 15-61.2 dB. Hearing results after type III tympanoplasty varied widely showing statistically significant improvement in mean post-operative PTA-ABG but there was a great variation. Key words: air bone gap, chronic otitis media, mastoidectomy, tympanoplasty