Topography of sphenoethmoidal cells based on cone beam computed tomography data

Introduction. Posterior extramural ethmoid air cells, particularly sphenoethmoidal cells (Onodi cells), are an important object of study in modern othorhinolaryngology due to their close relationship with critical neurovascular structures of the skull base and the high risk of intraoperative complications.

Aim. To systematize current data on the variants of structure, classification, and clinical significance of sphenoethmoidal cells based on cone-beam computed tomography (CBCT) data.

Objects and methods. An analysis of literary data was conducted, including original studies, systematic reviews, and meta-analyses found in PubMed, Google Scholar, and CyberLeninka databases. The search was performed using the following keywords in both English and Russian: «Onodi cell», «sphenoethmoidal cell» and «cone-beam computed tomography». Special attention was paid to works published in the last 10 years that used CBCT imaging methods.

Results. The review demonstrates a significant diversity of variants of extramural extension of posterior ethmoid cells. Based on CBCT data, a modified classification of Onodi cells is proposed and detailed, including five types (I – superior, II – superolateral, III – lateral, IV – superoposterior, V – intersphenoidal).

Conclusion. Knowledge of anatomical variations of sphenoethmoidal cells is of great importance for ensuring the safety of endoscopic interventions. CBCT imaging allows for a detailed assessment of these air cells and their relationship to critical anatomical neurovascular structures. A thorough preoperative evaluation, taking into account existing classifications, should become the standard for planning operations in the area of the sphenoid sinus and posterior ethmoid labyrinth to prevent iatrogenic injuries.

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