Outcome and lack of prognostic factors in stapes surgery

To analyze predictive factors of outcome after primary stapes surgery for otosclerosis.

Retrospective review of 139 patients with otosclerosis and 147 operations performed by the same senior surgeon with the same surgical technique.

Academic hospital and tertiary referral center.

All patients had documented preoperative and peroperative audiologic assessments and preoperative records. The mean age of patients was 44.31 years.

Stapedotomy with diode laser using Teflon prosthesis.

The bone conduction threshold changes, the improvement of pure-tone average air-bone gaps (PTA-ABGs), and ABGs for each frequency were analyzed using 0.5, 1, 2, and 4 kHz. Success rate was defined by postoperative ABG. Log-rank test was used to define significant factors.

At 24 hours postoperative, there was a significant deterioration in bone conduction threshold at 1, 2, and 4 kHz. However, at 4 kHz, the threshold remained significantly worse at longer term. There was a significant improvement of the PTA-ABG. Eighty-six percent of patients obtained a PTA-ABG of 20 dB or less. We also obtained a significant ABG closure on every frequency except on 4 kHz. Multivariate statistical analysis had not identified a predictive factor of hearing outcomes such as the anatomy of the facial nerve, the incus, the stapes footplate and the external auditory canal, the prosthesis crimping, bleeding, and surgical damage of the tympanic membrane.

In experienced hands, we observed a significantly transient depression of bone conduction hearing levels that was definitively present at 4 kHz. Peroperative difficult or abnormal situations did not seem to have an influence on the hearing outcome. Those statements will enable accurate preoperative counseling. It will also permit precise matching of future series to allow accurate comparisons.