Injection of Cultured Autologous Fibroblasts for Human Vocal Fold Scars

Objectives: This study evaluated the safety and effectiveness of injection of autologous fibroblasts into the lamina propria layer to treat vocal fold scarring. Study Design: A prospective, open-label, single arm, pilot study at a single tertiary care center. Methods: Autologous fibroblasts were expanded in cell culture from punch biopsies of the buccal mucosa of five human subjects with vocal fold scarring. Three doses of 1-2 x 10(7) cells/mL were injected into the superficial lamina propria layer of each scarred vocal fold at four-week intervals. The primary efficacy measure was an objective evaluation of the mucosal wave grade; secondary measures included acoustic analyses, a patient-completed voice handicap index (VHI) survey, and voice quality questionnaire. Safety assessments included clinical laboratory blood tests, vital signs, and monitoring for adverse events. Patients were followed for 12 months following the first treatment. Results: Mucosal wave grade improved and the improvement was sustained through month 12. Sustained improvements through month 12 were also noted for the VHI and voice quality questionnaire. Multiple injections of autologous fibroblasts into the lamina propria were well tolerated. Temporary otalgia was noted following treatment in two subjects. Conclusions: This study demonstrates that injection of autologous fibroblasts into the scarred vocal fold lamina propria layer is safe. Sustained trends for improved outcome were supported by 12-month data for mucosal wave grade, VHI, and voice quality questionnaire.