Autologous Platelet- and Extracellular Vesicle-Rich Plasma Is an Effective Treatment Modality for Chronic Postoperative Temporal Bone Cavity Inflammation: Randomized Controlled Clinical Trial

PURPOSE: To determine the efficacy of autologous platelet- and extracellular vesicle-rich plasma (PVRP) to treat chronic postoperative temporal bone cavity inflammation (CPTBCI) after exhausting surgical and standard conservative therapies. MATERIALS AND METHODS: Patients were randomly allocated to treatment with PVRP (PVRP group) or standard conservative methods (control group) in a setting of four once-monthly checkups and subsequent follow-up. The treatment outcome was measured with the Chronic Otitis Media Questionnaire-12 (COMQ-12), CPTBCI focus surface area, and CPTBCI symptom-free time after the fourth checkup. RESULTS: Eleven patients from each group completed the trial; 95% of patients suffered from chronically discharging mastoid cavity (the type of CPTBCI). Within four checkups, the COMQ-12 score decreased statistically significantly in the PVRP group (p < 0.001) but not in the control group (p = 0.339). The CPTBCI foci surface area decreased statistically significantly between the first and second checkups (p < 0.0005) but not between other checkups (p > 0.05) in the PVRP group. No statistically significant differences in CPTBCI foci surface area were detected between checkups in the control group (p = 0.152). Nine patients from the PVRP group and three patients from the control group were CPTBCI symptom-free at the fourth checkup. The median symptom-free time was 9.2 months (95% CI [7.4, 11.9]) in the PVRP group. Cumulatively, 49% of patients in the PVRP group remained CPTBCI symptom-free for 12.7 months after the fourth checkup. CONCLUSION: Autologous PVRP represents a novel additional and successful treatment modality for a chronically discharging radical mastoid cavity when the surgical and standard conservative treatment methods have been exhausted. TRIAL NUMBER: https://clinicaltrials.gov (NCT04281901).