PURPOSE: Postoperative pain and delayed wound healing are the main complications following anal surgery associated with poor quality of life. Hyaluronic acid (HA) supports tissue regeneration and rapid wound healing by promoting cell proliferation and migration. We investigated the effects of HA on perianal wound healing in a rat model. METHODS: Forty-eight 8-week-old Sprague-Dawley rats with perianal wounds created by biopsy punch were divided into 3 groups: simple dressing with gauze (control), dressing with topical HA film, and dressing with topical HA gel. HA agents were not reapplied postoperatively. Wound healing was evaluated by measuring the healed area, and histological analyses were randomly performed using hematoxylin and eosin and Masson trichrome staining. RESULTS: Fewer mean days were required for complete wound healing in the HA film and HA gel groups than in the control group (11.6 11.9 13.8 days, respectively; P = 0.010). The healed area in the HA film group on day 11 was larger than that in the HA gel and control groups (80.2% 61.9% 53.2%, respectively; P < 0.001). Histologically, the HA film group showed accelerated reepithelialization, a rapid transition to lymphocyte-predominant inflammation, and increased fibroblastic proliferation and collagen deposition compared to the other groups. There was no treatment-related toxicity in the HA application groups. CONCLUSION: Topical application of HA film to perianal wounds improves the wound healing rate in a rat model. This finding suggests a potential benefit of HA film application in promoting wound healing after anal surgery in humans.
