Safety and Efficacy of Endoscopic Dorsum Sellar Resection for Access to Retroinfundibular or Upper Clival Tumors (Korean Society of Endoscopic Neurosurgery-008)

Objective: The retroinfundibular and upper clival regions are challenging to access using the endoscopic endonasal approach 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 indications for endoscopic DSR in patients with craniopharyngioma. Methods: A retrospective study was conducted of patients who had undergone treatment with an endoscopic endonasal approach from January 2014 to January 2019. We identified a total of 50 patients who had undergone DSR. The indications 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: Of the 50 patients, 16 had been treated for craniopharyngioma, 30 for chordoma, 2 for pituitary adenoma, 1 for schwannoma, and 1 for chondrosarcoma. An extradural approach for DSR with posterior clinoidectomy was performed in 33 patients (66.0%) and an interdural transcavernous approach in 17 patients (34.0%). The overall gross total tumor resection rate was 92.0% (46 of 50 patients). Postoperatively, 28 of 33 patients (84.8%) with normal pituitary function preoperatively showed preservation of hormonal function postoperatively. Conclusions: DSR with or without posterior clinoidectomy is a challenging procedure that requires considerable effort and advanced surgical techniques. However, it can be safely performed with accumulating experience and a thorough knowledge of the surrounding anatomical structures.