Long-term follow-up of posttraumatic olfactory disorders

OBJECTIVE: This study aims to determine the long-term recovery rate of posttraumatic olfactory disorders and to evaluate whether a lateralized disorder influences recovery. METHOD: Olfactory function of 67 patients with posttraumatic olfactory disorders were examined twice using the `Sniffin` Sticks` test battery. Olfactory function was classified based on composite TDI (Threshold, Discrimination and Identification) score. Subjective impairment was rated by visual analogue scale ranging from 0 to 10. RESULTS: First and second examinations were conducted an average of 16.7 months and 74 months after trauma, respectively. From first to second examination, mean TDI score of the better nostril increased significantly, the number of patients with anosmia of the better nostril decreased, and number of hyposmic and normosmic patients increased. Subjective impairment decreased. Neither age, sex, nor side differences between nostrils affected improvement. CONCLUSION: After the follow-up period, in 27% of the patients the TDI score improved ≥ 6 points score and subjective impairment decreased. A follow-up period of more than 2 years is recommended.