Chondroitin sulfate hydrogel and wound healing in rabbit maxillary sinus mucosa

Objectives/Hypothesis: Chondroitin sulfate (CS) is a glycosaminoglycan in the extracellular matrix of all vertebrates. A biocompatible, nonimmunogenic, pliable hydrogel preparation of CS has recently been produced and has shown benefit in wound healing in murine and porcine epidermis. The objective of the current experiment is to compare the wound healing properties of CS hydrogel versus no treatment in wounds of the maxillary sinus mucosa. Study Design: Prospective investigation in an animal model. Methods: A 6 mm wound was created in bilateral maxillary sinuses of 17 New Zealand white rabbits. CS hydrogel (case) and no dressing (control) were randomly assigned to one side each as wound treatment. Wounds were examined ex vivo at 2,4,6, 10, and 14 day postinjury intervals. Wound diameter was measured microscopically by a blinded investigator. Representative specimens were examined histologically. Results: The CS disc was partially integrated into the wounds at the 4-day interval and completely integrated by the 6-day interval. The average wound diameters for the case versus control side were similar at 2 days (3.75 mm vs. 4.42 mm) but differed significantly at 4 days (2.86 mm. vs. 3.80 mm., P = .035). At 6 days, the wounds could not be discerned on either the case or control sides. However, histologic analysis revealed accelerated healing with the CS treatment. The treated wounds displayed respiratory epithelium as opposed to the squamous epithelium exhibited on the untreated sides. Conclusions: Despite some limitations, the New Zealand white rabbit is an effective model for the study of sinonasal wound healing. CS hydrogel accelerates wound healing in sinonasal mucosa at a 4-day endpoint. We propose that the CS hydrogel acts as a surrogate extracellular matrix, serving as a repository for cytokines and growth factors produced by the regenerating mucosa. It may also provide a structural framework for fibroblasts and epithelial regeneration. Further study is necessary to establish this relationship.