Efficacy of S53P4 Bioactive Glass for the Secondary Obliteration of Chronically Discharging Radical Cavities.

Objective: Present the results of the secondary obliteration of chronically discharging radical cavities using S53P4 bioactive glass (BAG). Study Design: Retrospective cohort study. Setting: Single-center study. Methods: A single-center retrospective cohort study was conducted of all patients that underwent secondary obliteration of persistently draining radical cavities using S53P4 BAG between 2011 and 2022. Patients with middle ear cholesteatoma were excluded. The main outcome was postoperative otorrhea, as indicated by Merchant grading. Results: In total, 97 patients were included. The median postoperative follow-up time was 3.9 years (range 0.5-10.4). Average time between the original canal wall down surgery and the secondary obliteration was 25.3 years (SD 11.7, range 2-66). At the most recent follow-up visit, a Merchant grade of 0 to 1 was observed in 95% of the cases. There were no cases of sensorineural hearing loss or facial palsy, one case developed a retro auricular skin defect and 1 patient developed CSF leakage. Minor complications were seen in 10 patients (10%). Ossicular chain reconstruction with a titanium prosthesis was performed in 42 cases, resulting in a median improvement of 11.2 dB in air conduction thresholds. In 9/42 cases (21%), closure of the postoperative air-bone gap to ≤20 dB was achieved. Twenty-five percent of cases could be discharged from out-patient visits. Conclusion: Revision of persistently draining radical cavities with BAG obliteration is feasible and results in a dry and safe ear in 95% of the patients, thereby enabling wearing of a conventional hearing aid. Out-patient visits could be ceased in 25% of the cases.