Olfactory Changes After Functional Endoscopic Sinus Surgery in Chronic Sinusitis Patients

Abstract

BACKGROUND: Chronic sinusitis has been recognized as a common etiology of olfactory loss. The olfactory loss can be treated by successful management of chronic sinusitis. However, On the other hand, when functional endoscopic sinus surgery (FESS) is utilized for the management of chronic sinusitis, it is possible to damage olfactory fillets by the procedures. Therefore, the influence of FESS on the olfactory functions in patients with chronic sinusitis was explored in this study. METHODS: Patients with chronic sinusitis who underwent bilateral FESS for treatment were included in this study. On the day before FESS, patients filled out a sinusitis questionnaire and took a phenyl ethyl alcohol (PEA) odor detection threshold test, a skin test, and acoustic rhinometry. Before the operation, the existence of nasal polyps was recorded. Six months after FESS, patients filled another questionnaire and took another PEA threshold test and acoustic rhinometry. The olfactory changes after RESS were evaluated by the questionnaires and PEA threshold. The olfactory change was correlated with the existence of allergic rhinitis, nasal polyps and nasal obstruction . RESULTS: Eighty-five patients were included in the study conducted between September, 1999 and February, 2003. Among 62 patients who reported olfactory loss before the operation, 36 subjects felt that their olfactory functions had improved after FESS. Among 68 patients whose bilateral PEA thresholds were higher than -6, 34 subjects’ thresholds were lowered after FESS. Among theses 85 patients, 142 unilateral PEA thresholds were higher than -6 before FESS. After surgery, the threshold were significantly lowered (p＜0.0001). The changes in olfactory function were not related to allergic rhinitis, nasal polyps and nasal obstruction. CONCLUSION: In this study , about half of the patients whose olfactory functions were impaired before FESS experienced improvement after the operation. However, worsening of olfactory function was noted in several patients. Therefore, careful manipulation during FESS needs to be emphasized in order to avoid damage to the olfactory function. (J Taiwan Otolaryngol Head Neck Surg 2004;39;49)