Functional anatomy of the uncinate process and its role in endoscopic sinus surgery

Background: A basic step of Functional Endoscopic sinus surgery - the most modern and revolutionary surgical treatment for chronic and recurring sinusitis, is removal of uncinate process to expose the infundibulum. The purpose of this study is to explore the functional role of uncinate process with special reference to endoscopic sinus surgery. Methods: A fixed dose of sterile methylene blue was sprayed into the nasal cavities of post endoscopic sinus surgery cases, 20 without uncinate process preservation and 20 with uncinate process preservation. The area of staining/deposition of the stain in the ethmoidal cavity and the maxillary sinuses was endoscopically observed. Results: Deposition of methylene blue was consistently found to be occurring in a larger area of the ethmoidal cavity including the maxillary sinus in post endoscopic sinus surgery cases without uncinate process preservation. Conclusion: Uncinate process probably acts as a protective wall by directing the allergen bearing and contaminated inspired air away from the sinuses and facilitating ventilation of the sinuses in the mucocilliary pretreated expiratory phase. Injudicious removal of the uncinate process especially in cases with allergic rhinosinusitis should thus expose the sinus mucosa to contaminated air.