Effect of Different Types of Concha Bullosa on Olfactory Function.

Introduction: This study aimed to compare the effects of different types of concha bullosa (CB) on olfactory function using paranasal computed tomography (CT) findings and the Sniffin' Sticks test.

Methods: A total of 107 patients (69 women and 38 men) were evaluated. The study group included 79 patients with CB, while the control group comprised 28 patients without CB. CB cases were classified into three subtypes according to the Bolger classification: lamellar (n = 28), bulbous (n = 25), and extensive (n = 26). Paranasal CT scans were assessed by a radiologist to measure the olfactory cleft width, the distance between the turbinate and septum, and the volume of the turbinate bullosa. All participants completed the SNOT-22 and NOSE questionnaires. Olfactory function was evaluated using the Sniffin' Sticks test, and examinations were conducted by an otolaryngology specialist.

Results: There were no significant differences between the groups in terms of age and gender (p > 0.05). The Sniffin' Sticks test score was significantly higher in the control group than in the CB group (p < 0.001). The control group had significantly higher odor scores than the lamellar and extensive groups (p = 0.002 and p = 0.042, respectively) but not the bulbous group (p = 0.133). The volume of the CB (vertical axis and horizontal axis of CB) was significantly greater in the extensive CB group than in the lamellar and bulbous groups (both p < 0.001). No significant differences were observed in the right, left, or total olfactory cleft widths among the four groups (p > 0.05).

Conclusion: Olfactory function, as measured by the Sniffin' Sticks test, was significantly better in the control group compared to the CB group. However, there were no significant differences in olfactory performance among the different CB subtypes. Additionally, olfactory cleft width did not differ significantly between groups. These findings suggest that while the presence of CB may be associated with reduced olfactory function, the subtype of CB and cleft width may not play a major role. Moreover, the reduction of olfactory function due to CB was minimal and not clinically meaningful.