Effects of compound betamethasone on vocal fold wound healing in rabbit model: A preliminary study

The compound betamethasone is widely used to prevent scarring in dermatology. This study aims to explore the effects of compound betamethasone on vocal fold (VF) wound healing.

Prospective animal study in rabbits.

Eighteen rabbits underwent bilateral VF stripping and three rabbits served as controls. 0.1 mL of compound betamethasone (1 mL: betamethasone sodium phosphate 5 mg and betamethasone dipropionate 2 mg) was injected into the right VF of each rabbit, and 0.1 mL 0.9% saline was injected into the contralateral VF. Endoscopy was performed for morphologic observation. Six larynges were harvested for histological analysis at 3 days, 7 days, and 1 month. The VFs were stained with hematoxylin and eosin (H&E), Alcian blue, and Masson' trichrome staining.

In morphological analysis, there was no visible difference between betamethasone-treated and saline-treated VFs at 3 and 7 days. After 1 month, more VF scars appeared on the saline-treated VFs than the VFs treated with betamethasone. Inflammatory cell number showed significant difference between both VFs at 3 days (p = .037) and 7 days (p = .045). No significant different was found in epithelial thickness at 1 month between the betamethasone and saline groups. The collagen in the saline-treated VFs was significantly denser than that of the betamethasone-treated group (p = .037). There was also a significant increase in the level of hyaluronic acid (HA) in betamethasone-injected VFs in comparison to the saline-injected VFs (p = .006).

Based on this study, compound betamethasone can improve VF healing. Our findings suggest that VF injection with compound betamethasone helps to minimize scarring by increasing HA level and decreasing collagen density.