Abstract

Introduction: Endoscopic sinus surgery is a common and effective method for addressing chronic sinonasal diseases. To minimize the risk of significant postoperative complications, a thorough understanding of the anatomical variations is crucial. The aim of this study was to evaluate the occurrence and classification of different Keros types by analyzing paranasal sinus CT scans, specifically focusing on the depth of the olfactory fossa in the population.

Methods: This retrospective, single-center analytical study was conducted on 127 patients who underwent non-enhanced paranasal sinus CT scans over a 1-year period. Ethical approval was granted by the Institutional Review Committee of Saraswathi Institute of Medical Science. The study utilized the SPSS statistical program (version 25) for data analysis.

Results: The average depth of the right olfactory fossa (OF) was 4.4±1.44 mm, while the left olfactory fossa had a mean depth of 4.5±1.5 mm. Based on the Keros classification, 15% of patients (19 out of 127) were classified as Keros I, 76% (97 patients) as Keros II, and 10% (13 patients) as Keros III for the right lateral lamella. For the left lateral lamella, 17.3% (22 patients) were classified as Keros I, 70.9% (90 patients) as Keros II, and 11.8% (15 patients) as Keros III.

Conclusions: Preoperative CT scans of the paranasal sinuses provide valuable insight into the architecture of the anterior skull base, which is essential for planning the surgical approach and preventing complications in endoscopic sinus surgery.