Retrospective analysis of early postoperative hearing results obtained after stapedotomy with implantation of a new titanium stapes prosthesis

Objective: To evaluate the early postoperative hearing results of a new titanium stapes prosthesis (K-Piston) implanted in patients with otosclerosis. Study design: A retrospective analysis of preoperative and early postoperative hearing thresholds. Setting: One tertiary referral and teaching hospital. Patients: Eighteen men and 40 women, mean age 47 years, with otosclerosis. Intervention: Primary stapedotomy. Main Outcome Measure: Main outcome measures were the mean gains in bone-conduction and air-conduction pure-tone thresholds, and pure-tone averages for different frequency combinations. Success and failure of the individual cases were presented using Amsterdam Hearing Evaluation Plots. Results: The overall postoperative air-bone gap for the frequency combination 0.5-1-2-4 kHz was 8.4 (standard deviation: 5.2) dB. In 79% of the patients the postoperative air-bone gap was less than 10 dB. Air-conduction improved even in higher frequencies, while the Carhart effect was not seen in most cases. In three patients a deterioration of bone-conduction was observed ranging from 11 to 16 dB sound pressure level (SPL), and in four patients the gain in air-conduction was insufficient (3-29 dB SPL) to close the preoperative air-bone gap to within 20 dB. Conclusion: The new low-weight, full-titanium stapes prosthesis with its slight rough surface and its good mechanical stability and biocompatibility can safely and successfully restore the function of the middle ear when implanted in patients with otosclerosis.