Olfactory Neuroepithelium in Olfactory Cleft Polyps: Do They Have Any Effect on Olfaction Results After Endoscopic Sinus Surgery?

Objective: How the presence of olfactory structures in olfactory cleft polyps (OCPs) affect olfaction function outcomes after surgical removal has not yet been investigated. In this study we aimed to assess the presence of olfactory structures in OCPs and correlate these findings with olfactory outcomes after endoscopic sinus surgery (ESS). Methods: Twenty seven patients with OCP underwent preoperative topical and systemic steroid treatment and ESS. Biopsies from the middle meatal polyps (MMPs) and OCPs were immunohistochemically analyzed for olfactory marker protein (OMP). The smell diskettes olfaction test was applied to patients at baseline, after steroid treatment (AST) and after ESS. Results: OCPs exhibited OMP staining more commonly and intensely compared to MMPs (p=0.008), however, there were no correlations between OMP staining scores and any of the olfaction scores (p>0.05). Steroid treatment increased smell function significantly (p<0.001), however, there were no significant differences between AST and after ESS smell scores (p=0.17). There were significant correlations between smell gains AST and final smell gains after ESS (r=0.665, p<0.001). Conclusion: OCPs contain olfactory neuroepithelium more commonly and intensely than MMPs in nasal polyp patients. However, surgical importance of this finding is controversial because removal of these polyps did not decrease smell function postoperatively in our study. Nasal polyp patients who will take steroid treatment pre-operatively must be informed that the success of ESS on olfaction depends on the response of the steroid treatment and ESS AST might not have additional favorable effect on smell function.