Self-reported course of olfactory impairment determines outcome for successful surgical intervention in nasal polyps with anosmia

Olfactory impairment is one of important symptoms of Chronic rhinosinusitis with nasal polyps (CRSwNP). However, the relationship between course of olfactory impairment and postoperative symptom improvement was still unclear.The aim of this study was to assess the relationship between the self-reported course of olfactory loss and the degree of improvement in olfaction to determine the timing for successful surgical intervention in improving olfaction in patients with CRSwNP.A total of 86 CRSwNP patients with loss of smell and undergoing functional endoscopic sinus surgery (FESS) were recruited consecutively. The self-reported course of smell lose before treatment was recorded. Olfactory function was recorded before and after FESS using TT Olfactometry.Fifty-seven patients demonstrated recovery of olfaction and 29 patients no-recovery. The average recovery time of smell loss in the study was 2.6 weeks. The course of smell loss showed moderate accuracy as a marker for determining the timing for successful FESS; with up to 4.5 years of self-reported smell loss being the cut-off point for recovery of smell following FESS.This study suggests that FESS in CRSwNP patients with self-reported significant olfactory impairment for less than 4.5 years may lead to improvement in olfaction.FESS in CRSwNP patients with self-reported significant olfactory impairment persisting for less than 4.5 years may lead to considerable improvement in olfaction in these patients.