The Olfactory Cleft Endoscopy Scale correlates with olfactory metrics in patients with chronic rhinosinusitis

Olfactory loss affects a majority of patients with chronic rhinosinusitis (CRS). Traditional objective measures of disease severity, including endoscopy scales, focus upon the paranasal sinuses and often have weak correlation to olfaction.

Adults with CRS were prospectively evaluated by blinded reviewers with a novel Olfactory Cleft Endoscopy Scale (OCES) that evaluated discharge, polyps, edema, crusting, and scarring of the olfactory cleft. Objective olfactory function was assessed using "Sniffin' Sticks" testing, including composite threshold-discrimination-identification (TDI) scores. Olfactory-specific quality of life was evaluated using the short modified version of the Questionnaire of Olfactory Disorders (QOD-NS). Interrater and intrarater reliability was assessed among 3 reviewers for OCES grading. Multivariate linear regression was then used to test associations between OCES scores and measures of olfaction, controlling for potential confounding factors.

The OCES score was evaluated in 38 patients and had a high overall reliability (intraclass correlation coefficient [ICC] = 0.92; 95% confidence interval [CI], 0.91 to 0.96). The OCES significantly correlated with objective olfaction as measured by TDI score (p < 0.001), with TDI score falling by 1.13 points for every 1-point increase in OCES score. Similar significant associations were found for threshold, discrimination, and identification scores (p < 0.003 for all) after controlling for age, gender, race, and reviewer/review. The OCES was also highly associated with patient-reported QOD-NS scores (p = 0.009).

A novel olfactory cleft endoscopy scale, OCES, shows high reliability and correlates with both objective and patient-reported olfaction in patients with CRS. Further studies to determine prognostic value and responsiveness to change are warranted.