Objective: The present study defines the extent of bone conduction loss that can be accounted for by stapes fixation.
Study Design: Prospective clinical evaluation.
Setting: Tertiary.
Patients: Two hundred consecutively operated cases. All patients have been operated by the first author.
Intervention: Posterior partial stapedectomy with a platinum-Teflon piston over a perichondral graft.
Main Outcome Measures: The bone conduction is studied preoperatively, 1 week, 1 month, and 1 year after surgery.
Results: There are at least 3 postoperative gain patterns that change with time, from 1 week to 1 year after surgery. These are patients with maximum gain at 1, 2, and 4 kHz.
Conclusion: The results suggest that these changes are due to the relation of the preoperative and postoperative oval window transfer functions. The gain in the 3 postoperative audiometric thresholds can be approximated by looking at the characteristics of the preoperative bone conduction audiogram.