Objective To evaluate if molecular markers of eosinophilia in olfactory enriched mucosa are associated with olfactory dysfunction. Study Design Cross-sectional study of tissue biopsies from 99 patients, and a further 30 patients who underwent prospective olfactory testing prior to sinonasal procedures. Methods Tissue biopsies were processed for analysis of inflammatory markers using qRT-PCR. Ipsilateral olfactory performance was assessed using the Sniffin Sticks threshold component and the UPSIT and age-adjusted data was correlated with inflammatory marker expression and clinical measures of obstruction from CT and endoscopy. Results Gene expression of the eosinophil marker CLC (Charcot Leyden crystal protein) was elevated in superior turbinate (ST) tissue in CRS with nasal polyps (CRSwNP) compared to ST and inferior turbinate (IT) tissue in CRS without nasal polyps (CRSsNP) and control patients (all p < 0.001 respectively). CLC in ST tissue was correlated with IL-5 and eotaxin-1 expression (all p<0.001; r = 0.65 and 0.49 respectively). CLC expression was strongly correlated with eosinophilic cationic protein levels (p<0.001; r=0.-76) and ST CLC expression was inversely related to olfactory threshold (p = 0.002, r = −0.57) and discrimination scores (p = 0.05, r = −0.42). In multiple linear regression of CLC gene expression, polyp status, radiographic and endoscopic findings with olfactory threshold, CLC was the only significantly correlated variable (p<0.05). Conclusions Markers of eosinophils are elevated in the ST of patients with CRSwNP and correlate with olfactory loss. These findings support the hypothesis that olfactory dysfunction in CRS correlates local eosinophil influx into the olfactory cleft.

MRI in idiopathic dysosmia yielded information regarding the diagnosis in one-quarter of cases. The implications of missing an intracranial neoplasm alone justify the cost of screening MRI for idiopathic dysosmia.

Compared to sprays, irrigations provide a more effective method of delivering topical agents to the posterior and superior aspects of the nasal cavity. The thorough distribution of irrigations has important clinical implications for improving the delivery of therapeutic agents to the olfactory mucosa.

Nasal obstruction plays a modulating, but not causative, role in SDB. Nasal interventions may improve subjective aspects of snoring and OSA but do not improve objective indicators of disease. Standardization of methods and higher evidence level studies will further clarify the benefit of nasal interventions in the treatment of SDB.

This study proposes 9 QIs for the diagnosis and management of patients with CRS. These QIs can serve multiple purposes, including documenting the quality of care; comparing institutions and providers; prioritizing quality improvement initiatives; supporting accountability, regulation, and accreditation; and determining pay-for-performance initiatives.