The Nasal Septal Swell Body May Have a Regulatory Role in Nasal Airway Passage That Depends on the Degree of Septal Deviation

Background: The nasal septal swell body (NSB) is a thickened area of the nasal septum with erectile tissues, located above the nasal floor. We hypothesized that the presence of the NSB in this space exerts favorable effects to generate laminar nasal airflow by developing its morphology as adjusted to nasal septal deviation (NSD). Patients and Methods: We objectively measured the NSB morphology in 152 patients by computed tomography (CT) and assessed its relationship with the width of the inferior turbinate (IT), the severity of NSD, and the patency of the nasal airflow passage (NAP). Results: In the patients with moderate or severe NSD, the mean widths of the NSB, IT, and NAP were significantly narrower at the convex side compared to the paired concave side, with the degree being more prominent in the severe-NSD group. A positive correlation was observed between the degree of the NSD angles and the difference in the widths of the NSB (r = 0.805) and IT (r = 0.609). Conclusions: These results imply novel roles of the NSB in the maintenance of physiological nasal airflow to generate a laminar airflow from the nostrils toward the middle nasal meatus at a constant rate.