Endoscopic ossiculoplasty: audiological and surgical outcomes from a multicenter experience with 292 cases.

Purpose
To evaluate surgical and audiological outcomes of different endoscopic ossiculoplasty (endo-OPL) techniques and prosthesis materials.
Methods
In this multicenter retrospective study, 292 patients underwent endo-OPL for various ossicular chain pathologies at three university hospitals between 2017 and 2023. We analyzed pre- and postoperative hearing metrics, perforation characteristics, surgical procedures, prosthesis types, and complication rates.
Results
The cohort showed significant audiological improvement, with the mean preoperative air-bone gap (ABG) reducing from 26.88 dB (SD ± 12.73) to 19.94 dB (SD ± 10.90) at the last follow-up (FU; mean 20.7 months ± 15.53) (p = 0.001), and a graft success rate of 94.2%. Significant postoperative ABG improvements were observed with bony partial ossicular replacement prostheses (PORP) (p < 0.001), titanium total ossicular replacement prostheses (TORP) (p = 0.008), and semi-synthetic TORP (p = 0.016). Both cement PORP and bony PORP groups showed consistent ABG improvements over two FU visits. Conversely, titanium based PORP and TORP demonstrated initial improvements but later showed deterioration. Prosthesis extrusion and dislocation rates were 8.4% and 4.2% for titanium PORP, and 0% and 5.2% for titanium TORP, respectively, at the last FU. Endo-OPL combined with additional mastoidectomy (n = 59) did not yield significant ABG improvements.
Conclusion
This multicenter study supports the efficacy of endo-OPL as a valuable technique to improve hearing outcomes in patients with conductive or mixed hearing loss. It highlights the superior performance of specific prosthesis materials and demonstrates that endo-OPL without additional mastoidectomy provides better hearing results, emphasizing the benefits of mastoid preservation in exclusive endoscopic procedures.