Audiometric Results of Stapedotomy Surgery for Otoscelorsis: Influence of the Radiological Stage

Background: The objective of this study was to identify a correlation between the radiological stage of otosclerosis and the pre- and postoperative audiometric results of patients who underwent a stapedotomy. Methods: Ninety-three patients with radiologically and surgically confirmed otosclerosis who underwent stapedotomy surgery and CT scanning within 18 months before the operation were included. The CT scans were interpreted by an otologist and a specialised radiologist to determine their radiological stage according to the classification of Veillon and Fraysse. The patients received a pre- and postoperative audiogram in the short and long term. Results: The preoperative bone conduction thresholds were higher in patients who presented with an advanced radiological stage of otosclerosis: 32.7 dB +/- 12.4 compared with those who presented with a less advanced radiological stage: 24.3 dB +/- 10.0. The preoperative air conduction thresholds were higher in patients who presented with an impairment of the round window: 58.1 dB +/- 13.5 compared with those who presented with no impairment of the round window: 48.7 dB +/- 14.5. The postoperative improvement in the air-bone gap was significantly higher for the localised foci: 16.9 dB +/- 8.6 versus 11.0 dB +/- 9.2, but only in the short term. Conclusion: There was a clinical radiological correlation with the preoperative results: In BC, there was a correlation with the radiological stage of Veillon and in AC, there was a correlation with impairment of the round window. The link between the radiological stage of otosclerosis and the postoperative audiometric results is less obvious. In the short term, the audiometric improvements in the air-bone gap were greater in patients in the early stages according to the Veillon classification, but this result was not sustained in the long-term.