Impact of Septal Deviation Severity on Maxillary Sinus Volume and Symptoms: A CT-Based Cross-Sectional Study

Deviated nasal septum (DNS) is known to contribute to sino-nasal symptoms; however, the specific relationship between the severity of deviation (Mladina grade) and quantitative structural changes, specifically maxillary sinus volume (MSV) remains underexplored. Understanding this relationship is essential for distinguishing between anatomical remodelling and mucosal disease. To evaluate the association between DNS severity and other anatomical variants with (1) maxillary sinus volume and (2) the prevalence of chronic sino-nasal symptoms using computed tomography (CT) imaging. A cross-sectional study was conducted on 140 adults with CT-confirmed DNS and chronic sino-nasal symptoms (> 12 weeks). DNS was categorised using the Mladina classification, and nine anatomical variants were evaluated. Maxillary sinus volume was calculated via CT morphometry. Data were analysed to correlate anatomical grades with symptom profiles.The cohort had a mean age of 34.4 years. Grade V DNS (36.4%) was the most frequent severity observed. Volumetric analysis revealed that ipsilateral sinus volume was significantly reduced in higher-grade DNS (p < 0.001), suggesting structural remodelling. Furthermore, specific variants such as concha bullosa and agger nasi showed a strong statistically significant association with nasal obstruction and breathlessness (p < 0.001). High-grade septal deviation is significantly associated with reduced ipsilateral maxillary sinus volume, likely due to compensatory anatomical remodelling. These findings suggest that beyond simple obstruction, severe DNS alters sinus architecture. Consequently, pre-operative volumetric assessment is recommended to guide personalised surgical strategies and manage patient expectations regarding symptom resolution.