Postoperative Olfactory Results in Chronic Rhinosinusitis with Nasal Polyposis According to Wound Healing Status

OBJECTIVES Postoperative wound healing status has not been considered in earlier studies on olfactory changes after surgery. This may be a factor accounting for the equivocal postoperative olfactory results. The aim of this study was to investigate postoperative olfactory results according to wound healing status. METHODS Fifty patients who underwent endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps with smelling disturbance were examined preoperatively, and at 6 months after surgery. Patients were divided into two groups according to postoperative Lund-Kennedy score: favorable and unfavorable wound healing. Preoperative ostiomeatal unit computed tomography (CT), such as Lund-Mackay score and olfactory cleft opacification score, clinical characteristics and olfactory function tests such as the butanol threshold test and cross-cultural smell identification test, and questionnaire responses were compared between the two groups. RESULTS There were no differences in preoperative clinical characteristics between the favorable and unfavorable wound healing groups. The favorable wound healing group displayed greater improvement of olfactory results after surgery than the unfavorable wound healing group. Postoperative olfactory improvement patterns showed a hierarchy from subjective to objective improvement and from threshold to identification improvement. Patients who had postoperative favorable wound healing but showed no success of olfaction were characterized by more severe preoperative subjective symptoms and higher olfactory cleft opacification, especially in the upper part of olfactory cleft on preoperative CT scan. CONCLUSION Wound healing status is an apparent risk factor for postoperative olfactory improvement. Moreover, preoperative opacification in the olfactory cleft may predict bad olfactory results after surgery, even in patients with favorable wound healing.