Tomographic classification proposal for safe endoscopic surgery of the sphenoid sinus

Abstract

Introduction: Sphenoidal sinus surgery and transsphenoidal approaches are commonly used by ENT surgeons and neurosurgeons to treat various pathologies. Radiological evaluation of this area is essential to identify neurovascular structures and their anatomical relationships. Objective: To propose a pre-surgical classification system for the sphenoid sinus, where risk groups are established in relation to neurovascular structures, with an alphanumeric code. Methods: Retrospective study, with simple computed tomography scans of the nose and paranasal sinuses of patients from the otolaryngology and head and neck surgery service of the General Hospital of Mexico. Classified according to the transverse diameter of the sphenoid sinus: I, 40 mm. The lateralization of included elements is their light: L, left; R, right; and B, bilateral. Anatomical element involved: N, optic nerve; V, internal carotid artery; and O, another type of element. Results: 200 imaging studies were analyzed. The average age of the population studied was 36.2 years. 49.5% were men (n = 99) and 50.5% (n = 101) women. Grade III presents a higher risk by compromising neurovascular structures in 90.6%. The general lateralization presented was 13.5% to the right side and 13% to the contralateral side. Isolated optic nerve protrusion occurred in 13.5% (n = 11), protruding internal carotid was found in 40% (n = 80), and in 7.5% (n = 15) both elements were found protruding towards the lumen of the sphenoid sinus. Conclusions: The proposed classification facilitates the transmission of information to the surgical team, prior to surgery, with a simple alphanumeric code, increasing the safety of the surgical procedure.

Keywords

• Sphenoid sinus. Internal carotid artery. Ophthalmic nerve. Functional endoscopic sinus surgery.