Bogdanov V, et al. - In this prospective study, researchers analyzed dynamics of olfaction after endoscopic sinus surgery (ESS) in relation to the effect of preoperative administration of glucocorticosteroids in chronic rhinosinusitis with nasal polyps (CRSwNP). Study participants included 52 CRSwNP patients divided into a control group (n = 31) subjected to ESS without preoperative steroids and a treatment group (n = 21) receiving orally administered glucocorticosteroids preoperatively. Using the extended Sniffin’ Sticks test battery (threshold, discrimination and identification [TDI] score), self-ratings of olfaction and olfactory testing were performed. TDI score significantly improved in 57% of patients and olfactory function remained unchanged in 43% after glucocorticosteroids. Additionally, there was a significant correlation between improvement in TDI score after steroids and 3 months postoperatively. In CRSwNP, glucocorticosteroids improved olfaction comparable to surgery. Moreover, changes in relation to steroids postoperatively predicted the olfactory outcome. As far as olfactory dynamics are concerned, it could be shown that olfactory function increased 1 month after surgery and decreased 3 months after surgery.