Variations in Ciliary Beat Frequency Based on Chronic Rhinosinusitis Endotype and Phenotype

BackgroundChronic rhinosinusitis (CRS) is traditionally classified into CRS with or without nasal polyps and more recently into eosinophilic and non-eosinophilic endotypes. Limited research exists on the relationship between CRS subtype and mucociliary function. This study compares ciliary beat frequency (CBF) across CRS subtypes.ObjectiveTo investigate CBF across different CRS subtypes and validate spectrally encoded interferometric microscopy (SEIM) against phase contrast microscopy (PCM) for measuring CBF.MethodsSinonasal mucosa from endoscopic endonasal surgery cases were imaged ex vivo at physiologic temperature with PCM and SEIM. CBF measurements were compared between disease states (control vs chronic rhinosinusitis with nasal polyps (CRSwNP) vs chronic rhinosinusitis without nasal polyps (CRSsNP) and control vs eosinophilic chronic rhinosinusitis vs noneosinophilic chronic rhinosinusitis), as well as between PCM and SEIM.ResultsCRSwNP mucosa (5.77 ± 0.12 Hz) had significantly lower CBF compared to control (6.23 ± 0.11 Hz; p=0.001). Both eosinophilic rhinosinusitis (5.74 ± 0.16 Hz; p=0.005) and noneosinophilic CRS mucosa (6.00 ± 0.08 Hz; p=0.03) had significantly lower ciliary beat frequency compared to control (6.28 ± 0.11 Hz). There was no significant difference between PCM (7.65 ± 0.60 Hz) and SEIM (7.64 ± 0.51 Hz) as a means of evaluating CBF (p=0.36).ConclusionAmong CRS subtypes, eosinophilic, noneosinophilic, and CRSwNP are associated with lower ciliary beat frequency when compared to healthy controls. SEIM may have value in measuring ciliary beat frequency.