Background: Wound healing of the nasal mucosa after endoscopic sinus surgery (ESS) is frequently complicated by scaring and consequently recurrences are encountered. Methods of optimizing results have been sought. In the present study we evaluated the effects of a powerful antioxidant, astaxanthin, on nasal mucosa healing after surgery, comparing it to the extensively studied properties of dexamethasone. Materials and Methods: 63 Wistar rats were used. The nasal mucosa from one side was damaged employing the brushing method. They were randomly divided into three experimental groups, one treated with astaxanthin, the second treated with dexamethasone and the third one acted as the control and was given normal saline. The rats were killed on days 5, 14 and 28 following injury. We observed the temporal evolution of the wound healing process and quantified the results by assessing four parameters: the epithelial thickness index (ETI), the subepithelial thickness index (STI), the goblet cell count and the subepithelial fibrosis index (SFI). Results: At 28 days, the ETI was significantly lower in the astaxanthin group (p < 0.05) compared to the other two groups. The STI was also lower in the astaxanthin group (p < 0.05), but comparable to the dexamethasone group at 28 days. The goblet cell count was higher in the astaxanthin group. The SFI had similar results in both dexamethasone and astaxanthin groups, with lower values compared to the control group. In the astaxanthin group there was no synechia formation. Conclusion: Astaxanthin given in the post injury period significantly decreases fibrosis, inhibits synechia development and significantly decreases subepithelial fibrosis. Moreover, it has no general or local toxic effects.

Introduction. The aim of the present study is to evaluate the presence of biofilms in patients with chronic rhinosinusitis (CRS), with or without nasal polyps, and their relationship to eosinophils and plasma cells. We compared the results with those obtained in nonCRS patients. Methods. A total of 50 patients were included in the study, 30 CRSwNP patients, 10 CRSsNP cases and 10 control patients who were operated for deviated septum. Biofilm detection was performed by means of H&E staining and SEM. Eosinophil and plasma cell values were recorded and compared between groups. Results. Biofilms were identified in 30 patients (60%), 76.6% (23 out of 30) of the CRSwNP patients, 70% (7 out of 10) of the CRSsNP patients and none of the septoplasty patients. Eosinophil and plasma cell values were more elevated in CRS patients, being strongly correlated to biofilm presence and nasal polyposis. Conclusion. Biofilm presence was demonstrated in many of the CRS patients, with no evidence in the control cases. Our study findings indicate that inflammatory cell counts are higher in patients with CRS compared to controls, but also more elevated in patients with polyposis. In biofilm-positive patients, eosinophil and plasma cell counts were greater than those in patients without biofilms, demonstrating the proinflammatory action of the biofilm in the sino-nasal pathology.