Mapping the surgical landscape: CT evaluation of nasal cavity and paranasal sinuses anatomical variants in patients undergoing FESS—a tertiary care centre based cross sectional study

Abstract Background Functional endoscopic sinus surgery (FESS) requires precise preoperative mapping of these variants, which is best achieved through computed tomography (CT). Knowledge of the anatomical variants of the nasal cavity and paranasal sinuses is also disease-specific and is valuable in surgical outcomes. Our objective was to evaluate anatomical variants of the nasal cavity and paranasal sinuses using CT in patients undergoing FESS and to determine their association with intraoperative findings and clinical symptoms. Results A total of 90 patients aged 18 to 60 years with chronic sinonasal symptoms were evaluated using 128-slice multidetector CT. Anatomical variants such as nasal septal deviation, concha bullosa, haller cells, onodi cells, variations in the uncinate process and skull base anatomy (keros classification) were documented. These findings were correlated with intraoperative data from FESS. The most common symptom was nasal obstruction (94.4%). CT findings revealed maxillary sinus mucosal thickening in 100% of cases and bony erosion in 94.4%. Nasal septum deviation was seen in 56.7%, concha bullosa in 51.1% and onodi cells in 15.6%. CT showed excellent concordance with intraoperative findings, particularly for nasal septum deviation (100%) and middle turbinate anomalies (95.7%), with statistically significant correlations ( p < 0.001). Conclusions CT imaging is an essential preoperative tool in FESS for detecting sinonasal anatomical variants. Accurate recognition of these variants can significantly improve surgical planning and minimize complications.