Anatomical variants of the nasal cavity and paranasal sinuses in clinical and surgical practice
DOI:
https://doi.org/10.2478/AMB-2026-0025Keywords:
nasal cavity, paranasal sinuses, anatomical variations, functional endoscopic sinus surgery (FESS), radiological imaging, surgical risks, skull baseAbstract
Abstract. The nasal cavity and paranasal sinuses form an anatomically intricate and highly variable region that plays a vital role in the physiological functions of the upper respiratory tract and is intimately associated with a wide range of pathological and surgical considerations. Anatomical variations in this area – such as concha bullosa, septal deviation, Haller and Onodi cells – are frequently linked to impaired mucociliary clearance, obstruction of natural drainage pathways, and an increased risk for the development of chronic rhinosinusitis. Moreover, the presence of such variations significantly influences the planning and execution of functional endoscopic sinus surgery (FESS) and transnasal approaches to the skull base, increasing the likelihood of complications involving the optic nerve, internal carotid artery, or orbital structures. This review aims to provide a structured analysis of the most clinically relevant anatomical variants of the nasal cavity and paranasal sinuses, grounded in contemporary literature from the past decade across radiological imaging, anatomical studies, and skull base surgery. It explores the relationship between structural anomalies and the frequency and severity of sinonasal pathology, as well as their implications for endoscopic surgical practice. Special attention is given to surgical hazards posed by variations such as dehiscent lamina papyracea, accessory maxillary ostia, and pneumatization of the anterior clinoid process. The review includes tabular and graphical representations illustrating the associations between specific anatomical features and their related clinical and surgical risks. This integrative approach is intended to support clinicians in enhancing diagnostic accuracy, optimizing preoperative planning, and minimizing intraoperative complications through a personalized anatomical understanding of this region.
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