Is the Extent of the Preoperative Air-Bone Gap an Indictor of Potential Success in Stapedectomy?

Abstract

Objectives:

(1) Could preoperative air-bone gap (ABG) magnitude act as a predictor of postoperative outcome in patients undergoing stapedectomy for otosclerosis? (2) If this were to occur, is it frequency specific?

Methods:

Retrospective case series from January 2010 to December 2012 in a tertiary London teaching hospital. Intervention: Laser stapedectomy using Smart Nitinol stapes prosthesis. Main outcome measure: Audiometric. Retrospective analysis comparing preoperative and postoperative air-bone gap in 302 patients undergoing stapedectomy. Patients were stratified into subgroups according to their preoperative ABG and this was compared to their postoperative result of air-bone closure. In addition, for each commonly tested frequency (0.5, 1, 2, 3, 4 kHz) the preoperative and postoperative air-bone gap were analyzed in order to ascertain whether the preoperative ABG could act as a predictor. Having not passed normality testing, Wilcoxon matched paired signed rank test and Spearman rank coefficient were used for analysis.

Results:

Throughout the statistical analysis, preoperative ABG correlated most strongly with net difference in postoperative ABG (P < .0001). For each commonly tested frequency assessed this demonstrated a “very strong” positive correlation. As such, the greater the preoperative ABG, the greater the closure obtained through stapedectomy in this series.

Conclusions:

In performing stapedectomy for otosclerosis, our series suggested the preoperative ABG may have a role in preoperative patient counseling and consent but is unable to predict success in stapedectomy surgery.