Measurement of Nasal Nitric Oxide in Chronic Rhinosinusitis and Its Relationship to Patient-Reported Outcome: A Longitudinal Pilot Study.

Irrespective of occluded or open ostiomeatal complexes, no statistically significant differences in nNO were found in CRS compared with healthy controls using aspiration and humming methods. Treatment of CRS improved sinus patency without accompanying a significant change in nNO. This study can therefore not conclude that nNO can be used as a diagnostic tool for CRS without polyposis.