Influência do Rinne audiométrico pré-operatório no sucesso técnico da estapedotomia

Introduction: The aim was to determine the influence of preoperative air-bone gap (ABG), as independent prognostic factor, on technical success of stapes surgery. Methods: We reviewed charts of 118 case stapedotomies with an incomplete ABG closure (ABG>10dB), and 285 control stapedotomies with a complete ABG closure (ABG≤10dB). We retrospectively recorded preoperative air-conduction, bone-conduction, and ABG. We then classified both case and control groups into two categories according to the preoperative mean air-bone gap (ABG≤30dB and ABG>30dB). Multivariate logistic-regression model was used for casecontrol comparisons. Results: Thirty-five case surgeries had a preoperative ABG≤30dB (percent [%], 29.6) against 83 case surgeries had a preoperative>30dB (%, 70.4). On the over hand, 118 control surgeries had a preoperative ABG≤30dB (%, 41.4) against 167 control surgeries had a preoperative ABG>30dB (%, 58.6). The mean preoperative ABG was 41.7dB in case group (standard deviation [SD], 7.7) and 32.4dB in control group (SD, 7.5). Preoperative ABG≤30dB was associated with better technical success (odds ratio, 1.68; 95% confidence interval [CI], 1.06 to 2.65). Association persists when age, race, side ear and diameter of prosthesis were included in the multivariate model (adjusted odds ratio, 1.70; 95% CI, 1.07 to 2.7). Conclusions: Our findings suggest that ABG can be a valid prognostic factor to predict technical success of stapes surgery. The magnitude of ABG closure is superior in cases with minor preoperative ABG when compared with those with greater preoperative ABG.