ABSTRACT
BACKGROUND AND OBJECTIVES: Endoscopic sinus surgery (ESS) improves olfactory dysfunction due to chronic rhinosinusitis. Cross-Cultural Smell Identification test (CC-SIT) is known to be one of the useful methods to assess the olfactory dysfunction. We assessed the influence of ESS on olfactory function by using symptom scores and CC-SIT, and determined the clinical validity of CC-SIT. MATERIALS AND METHODS: 151 patients with chronic rhinosinusitis who had received ESS were evaluated. Prior to and three months following the surgery, each patient was requested to mark a 5-point scale ranging from normosmia to anosmia. Preoperative and postoperative CC-SITs were performed for 20 patients who complained of olfactory dysfunction. To evaluate the clinical validity of CC-SIT, we assessed the correlations between CC-SIT scores, symptom scores and CT scores using the Lund-Mackay CT scoring system. RESULTS: There were a significant decrease in the symptom scores and an increase in the CC-SIT scores after ESS. However, normosmia was achieved in only 38.5% (25/65) of the patients determined by symptom scores and 23.5% (4/17) by CC-SITs. There were significant correlations between CC-SIT scores, symptom scores and CT scores (r=-0.416, r=-0.357, r=0.510, p<0.05). CONCLUSION: Although the average postoperative olfactory ability after ESS was in the hyposmic range, ESS could improve the olfactory ability in patients with chronic rhinosinusitis. The 5-point scale and the CC-SIT scores reflected well the severity of olfactory dysfunction in patients with chronic rhinosinusitis, and therefore, we recommend them as convenient and practical tools to assess olfactory ability before and after ESS.