Vocal Fold Scar Treatment via Controlled Dexamethasone Delivery With a Light‐Activatable Implant

Objective Intralesional steroid injections for vocal fold (VF) scarring are rapidly cleared, limiting their effectiveness. This study evaluates the efficacy of a light‐activatable dexamethasone implant compared to a single steroid injection for VF scar healing. Methods Ten rabbits underwent endoscopic VF injury and were treated with either a dexamethasone injection or a light‐activatable implant; injured‐only and no‐injury VFs served as controls. On days 0 and 21, VF implants were irradiated with a near‐infrared pulsed laser for 1 min. Larynges were harvested after 42 days. High‐speed video (> 10 kHz) of excised larynges captured VF vibrations for kymographic analysis. Normal force, structural stiffness, and displacement were measured. Data were analyzed with appropriate statistical tests. Results Compared to injury‐only VFs, implant‐treated VFs demonstrated significantly reduced normal force and stiffness (5.28 ± 0.77 mN vs. 2.34 ± 0.66 mN, p < 0.0001; 17.74 ± 2.45 mN/mm vs. 6.80 ± 1.32 mN/mm, p < 0.0001), and increased displacement at 1.96 mN (0.14 ± 0.02 mm vs. 0.29 ± 0.05 mm, p < 0.0001) along the injury zone. Implant‐treated VFs exhibited larger amplitude ratios and improved tissue architecture than untreated scars. No differences in quantitative measures were observed between implant‐treated and injection‐treated groups. Conclusion A light‐activatable dexamethasone implant improved VF biomechanics, vibratory behavior, and histological outcomes in a rabbit injury model comparable to a single steroid injection. This novel approach shows promise for delivering controlled, repeatable therapy to VF scars.