The importance of side difference in nasal obstruction and rhinomanometry: a retrospective correlation of symptoms and rhinomanometry in 1000 patients

Clin. Otolaryngol. 2012, 37 , 17–22 Objectives:  The correlation between subjective and objective outcomes of nasal obstruction is still a matter of controversy. The aim of this study was to determine the minimal level of side difference in nasal airway resistance (NAR measured by Broms’ v 2 ) between the two nasal cavities, which could be discerned subjectively by the patient on a visual analogue scale (VAS). Nasal airway resistance was calculated from rhinomanometric measurements of nasal airflow and transnasal pressure after decongestion of the nasal mucosa. Design:  A retrospective study. Setting:  ENT department, Vaxjo Central Hospital, Sweden. Participants:  We studied 1000 active anterior rhinomanometries from patients with nasal obstructions. Main outcome measures:  We compared the side difference of nasal airway resistance with the side difference of VAS estimated immediately prior to the rhinomanometry. Each measurement was performed after nasal decongestion. Results:  When the difference in nasal airway resistance between the two nasal cavities was larger than 20° (Broms’ v 2 ) or R 2  > 0.36 Pa/cm 3 /s, we found a significant correlation between side differences of the objective measurement and the subjective assessment (VAS). With a nasal airway resistance side difference over 20°, an additional 20° difference corresponded to a 0.9 centimetre average VAS change. The more obstructed side of the nose could be determined by VAS in 823 (82.3%) of 1000 patients. Yet, 177 (17.7%) patients had a paradoxical sensation of nasal obstruction with the low resistance side of the nose experienced as the most congested side. Conclusion:  A significant correlation between the side differences of nasal airway resistance and VAS can serve as a supplement to rhinoscopy in decisions about nasal surgery. This study also showed that in 17.7% of patients, there was a negative correlation between subjective and objective evaluations of nasal airway resistance. But in this group, the nasal airway resistance side difference was mostly under 20°.