Olfaction after Endoscopic Sinus Surgery of Chronic Rhinosinusitis

Abstract

Objectives: Chronic rhinosinusitis (CRS) is one of the most common causes of olfactory dysfunction. After endoscopic sinus surgery (ESS), olfactory function may improve in most cases, but may not in others. The purpose of this study was to investigate the prognostic factors for olfaction improvement after endoscopic sinus surgery in CRS. Methods: A total of 103 patients (175 nostrils) with CRS who underwent ESS were studied. We performed olfactory function test for all patients using the butanol threshold test (BTT) and Cross Cultural Smell Identification test (CC-SIT) preoperatively and postoperatively. The patients’ subjective symptoms were also recorded using the visual analog scale (VAS) pre- and postoperatively. We also analyzed the duration of disease and preoperative computed tomography by Lund-Mackay score. Results: The improvement of olfactory function after ESS in patients with longer duration of symptoms was not significantly lower than in patients with shorter duration. In multivariable study, anosmics had better improvement than hyposmics in recovery of olfaction. There were significant differences in anterior ethmoid involvement between responder and non-responder group. Conclusions: The improvement of olfaction after ESS mainly depends on the degree of preoperative olfactory function and involvement of anterior ethmoid involvement. Therefore, for the better outcome of ESS especially in olfactory function, early and proper treatment (including ESS) for CRS will be necessary.