Assessment of nasal airflow by objective tests and olfactory function by threshold?suprathreshold tests before and after septoplasty

Objective: Aim of our study was to evaluate nasal airflow by objective tests and olfactory function by threshold ? suprathreshold tests before and after septoplastyMaterial and Methods: This study was done in between January 2010 and July 2010. Olfactory function was assessed in 31 patients who underwent septoplasty. Assesment of alteration in nasal air flow was done by using objective tests of peak flowmetry (PF) and anterior rhinomanometry (RM). Olfactory function was evaluated by subjective tests of smell threshold, discrimination and identification using Sniffin? Sticks test battery. Measurements were performed preoperatively and 8 weeks postoperatively. In addition to analysis applied to the whole group, assessments of olfactory function was compared between two separate groups according to location of the septum deviation as inferior (18 cases) and superior (13 cases). In order to evaluate loss of olfactory function due to general anesthesia, we used 14 patients who had surgery of any cause other than nasal pathology under general anesthesia; direct laryngoscopy, tympanoplasty and tympanomastoidectomy; as our control group. To compare pre and postoperative data statistically, we used t test and chi square tests for all patient groups; and Wilcoxon signed rank test for comparison of inferior and superior septum deviation cases and control group.Results: The PF and RM tests applied to patient groups revealed statistically significant postoperative improvements in the nasal airflow (p<0.05). No statistically significant differences were found in both groups and inferior/superior septum deviation groups in terms of pre and post operative values of odor threshold, discrimination, and identification tests and TDI values (threshold, discrimination, identification) where data of all three tests were assessed in combination (p>0.05). Later on septal surgery measurements revealed significantly higher odor thresholds in control group compared to pre and postoperative period (p<0.05). Whereas no such conclusions were made for odor threshold, smell identification and combined TDI values (p>0.05).Conclusion: Improvement of nasal air flow was found by objective measurements after septoplasty. In contrast, no statististically significant changes were found in subjective smell tests applied during preoperative and postoperative periods. The present data of our study indicates that increased air flow does not cause improvement of olfactory function and no adverse changes were observed due to the surgery. It was not possible to explain the improvement determined only in the smell discrimination test in the control group. However, it may be hypothesized that basic assessments gathered from the control group are stable, as no statistically significant differences were found in smell threshold, smell identification and combined TDI scores when pre and postoperative measurements were compared.