Radiological Evaluation of Sphenoid Sinus Anatomy and Its Critical Relationships: Implications for Endoscopic Surgery

Introduction:The sphenoid sinus (SS), owing to its deep and central location, poses significant diagnostic and therapeutic challenges, especially during endoscopic sinus surgery.Its close anatomical relationships with vital neurovascular structures such as the optic nerves (ONs) and internal carotid arteries (ICA) necessitate a comprehensive understanding of its variable anatomy and pneumatization patterns.Detailed anatomical knowledge is crucial to minimize iatrogenic injury and ensure surgical safety and efficacy.Materials and methods: This retrospective cross-sectional imaging study analyzed computed tomograms of 55 patients (29 males and 26 females), aged between 18 and 75 years.The evaluation focused on SS anatomy with particular emphasis on septation patterns, pneumatization types, ON relationships, and other variations, including bony dehiscence and clinoid process pneumatization.Results: A high prevalence of anatomical variations was noted.Deviated intersinus septa were observed in 35% of cases, with 16.5% terminating on the ON canal.The stellar type of pneumatization was the most common, seen in 62% of patients.Optic nerve relationships demonstrated significant variability: 56.36% were close without indentation, 23.64% indented, 16.36% traversed through the sinus, and 3.64% in close proximity to both ethmoid and SS.Additional findings included bony dehiscence in 23.64%, anterior clinoid process (ACP) pneumatization in 29.1%, and posterior clinoid process (PCP) pneumatization in 7.27%. Conclusion:The study highlights the considerable variability of SS anatomy and its critical implications for endoscopic sinus surgery.Preoperative CT imaging plays an indispensable role in identifying these variations, which frequently predispose patients to ON injury.A thorough understanding of these anatomical relationships is essential to enhance surgical precision and reduce the risk of complications.