Safety and efficacy of endoscopic dorsum sellar resection for access to retro-infundibular or upper clival tumors (KOSEN-008∗).

Abstract Objective The retro-infundibular and upper clival regions are challenging to access using the endoscopic endonasal approach (EEA) because these regions are obstructed by the dorsum sellae and posterior clinoid processes. We evaluated the safety and clinical efficacy of endoscopic dorsum sellar resection (DSR) and identified the optimal indication of endoscopic DSR in patients with craniopharyngioma. Methods A retrospective study was conducted in the patients treated with EEA between January 2014 and January 2019. We identified a total of 50 patients who underwent the DSR. Indication for DSR included the following: (1) a tumor involving the upper clivus, (2) a tumor located behind the dorsum sellae, and (3) a tumor involving the interpeduncular or prepontine cistern. We evaluated the clinical outcomes, postoperative endocrinological status, and surgical morbidities. Results The patients group included 16 craniopharyngiomas, 30 chordomas, two pituitary adenomas, one schwannoma, and one chondrosarcoma. Extradural approach for DSR with posterior clinoidectomy was performed in 33 patients (66.0%) and interdural transcavernous approach in 17 patients (34.0%). The overall gross total resection rate of the tumor was 92.0 % (46 of 50 patients). Postoperatively, 28 of 33 patients (84.8%) with preoperative normal pituitary function showed preservation of hormonal function. Conclusion DSR with/without posterior clinoidectomy is a challenging procedure that requires considerable efforts and advanced surgical techniques, however, it can be safely performed by accumulating experience and thorough knowledge of the surrounding anatomical structures.