Endoscopic sinus surgery improves olfaction in nasal polyposis, a multi-center study.

BACKGROUND A positive effect of Endoscopic Sinus Surgery (ESS) as sole treatment on olfactory thresholds and sense of smell in patients with nasal polyposis has been questioned. The aim of this study was to test the hypothesis that ESS has a positive effect on sense of smell and olfactory threshold in nasal polyposis. METHODS Uncontrolled post-hoc analysis of a prospective study of 160 patients, > or = 18 years, with bilateral nasal polyps that underwent ESS to treat bilateral nasal polyposis. The effect of ESS was assessed with an olfactory threshold test, a diary score and a smell and taste score, pre-, and post-ESS. RESULTS All three effect measures were improved from pre-ESS to post-ESS. Olfactory threshold increased from 0.0 pre-ESS to 3.0 (p < 0.001), two weeks after surgery, and the smell diary score decreased from 3.0 to 1.7 during the same period (p < 0.001), i.e. improvement. The smell and taste score increased from 1.0 pre-ESS to 2.0 post-ESS (p = 0.002). Overall, the results were similar for patients with and without previous surgery, as well as for men and women. CONCLUSION ESS without concomitant medical therapy seems to improve both sense of smell and olfactory thresholds in patients with nasal polyposis in the short term.