Is Computed Tomography Imaging of Deviated Nasal Septum Justified for Obstruction Confirmation?

Third-party payers request objective confirmation of the nasal septum deviation (NSD) severity by computed tomography (CT) before authorizing financial support for septoplasty. Previous studies have provided contradictory results related to the link between obstruction severity and CT-measured angle of the NSD. The aim of this study was to investigate whether the diverse CT morphology of NSDs (including previously neglected types and shapes) could predict obstruction severity. The study included 225 patients with NSD. The CT morphology of the septum was analyzed using 5 different classifications of NSD that are commonly used in the clinical practice and research. The angle of NSD was also measured. Nasal obstruction was assessed by the Nasal Obstruction Symptom Evaluation (NOSE) questionnaire. A relationship between CT morphology and the angle of the NSD and NOSE scores was analyzed using appropriate regression models. Patients with NSDs located in the anterior part of the septum always have some degree of nasal obstruction, while those with posterior NSDs did not necessarily report obstruction symptoms no matter how complicated NSD they have. Regression analysis did not reveal any causal relationship between NOSE scores and CT morphology and the angle of NSD. The presence of spurs and whether they divide nasal passages have no statistically significant predictive effect on the obstruction severity. The CT morphology and the angle of the NSD could not predict severity of the nasal obstruction. Requesting CT examination just to objectively confirm nasal obstruction is not justified.