The Effect of a Hyaluronic Acid–Based Nasal Pack on Mucosal Healing in a Sheep Model of Sinusitis

Background A hyaluronic acid–based nasal pack has been shown previously to have a beneficial effect on mucosal healing in a healthy sheep model. However, endoscopic sinus surgery (ESS) usually is performed in the presence of infection and inflammation. The aim of this study was to examine the efficacy of hyaluronic acid–based nasal packing on mucosal healing in a sheep model of chronic sinusitis. Methods A standardized sheep model of chronic sinusitis was used. Full-thickness mucosal injuries were performed under endoscopic guidance with a microdebrider. Adjacent wounds were created between the lateral nasal wall and the ethmoid turbinate. Then, the injuries were either packed with a dissolvable hyaluronic acid–based pack or left unpacked to serve as a control. Serial biopsies of the healing mucosa were performed at days 28, 56, 84, and 112 postsurgery, and the presence or absence of adhesions between the ethmoid turbinate and lateral nasal wall was noted. The biopsy specimens were assessed for reepithelialization and epithelial height using light microscopy, and for reciliation using scanning electron microscopy. Results There was no significant difference in reepithelialization or relative epithelial height between the packed sides and the control sides at any time point. There was a statistically significant difference in reciliation between the two groups at day 112 but this was not deemed clinically significant. The packing had no significant effect on adhesion formation. Conclusion In the sheep model of chronic sinusitis, a dissolvable hyaluronic acid–based pack did not have any significant effect on mucosal healing or adhesions formation after ESS, as assessed by examining reepithelialization, epithelial height, reciliation, and the presence of adhesions.