SUPRAORBITAL AND ENDONASAL APPROACHES: TAILORING SURGICAL TECHNIQUES FOR TUBERCULUM SELLAE MENINGIOMAS BASED ON PREOPERATIVE GRADING SYSTEMS.

Background Tuberculum sellae meningiomas (TSM) tend to compress the optic apparatus and an ideal surgical route, whether transcranial or endonasal, is still debated. Another issue is if the minimally invasive supraorbital (SO) approach offers the same results compared to the more invasive craniotomy. Aiming to guide approach selection, preoperative grading systems have been described. Method All cases of TSM treated from 2013 to 2018 by extended endoscopic endonasal (EEA) or SO approach have been reviewed and classified according to three preoperative grading system: McDermott scale, Optic Nerve Laterality Score and Yaşargil criteria. Results A total of 15 patients with TSM were treated with the EEA (n=6) or the SO (n=9) approach. Globally, gross total resection was obtained in 87% (n=13) of cases and was higher with the SO (100%, n=9) compared to the EEA (67%, n=4). Visual function improved in all but one patient (n=14). Compared to the EEA group, patients treated by the SO approach had larger tumors (32.3 mm vs 24.5 mm), higher rate of optic canal invasion (4/9 vs 0/6) and arterial encasement (6/9 vs 1/5). Patients with McDermott total point of 1-2 (7/15) were treated mainly by the EEA; all patients with McDermott total score ≥3 (8/15) were treated by the SO approach. All patients with optic canal invasion (4/15) and lateral extension of the tumor (ONL score = 1-3) were treated by the SO approach. Conclusions The SO and EEA are two minimally invasive approaches safe and effective for treating TSM. For tumors with lateral extension (optic nerve laterality score = 1-3), larger diameter (> 30-35 mm), vascular encasement or optic canal involvement (McDermott total point = 2-3), the SO craniotomy is preferred. For small and median tumors with no optic canal invasion or vascular encasement (McDermott total point = 1-2), the EEA represents a valid option.