Combined Endoscopic Endonasal and Video-microscopic Transcranial Approach with Preoperative Embolization for a Posterior Pituitary Tumor

Background: Posterior pituitary tumor is rare, and its optimal surgical strategy is undetermined. Surgical removal of posterior pituitary tumors is often complicated by their hypervascularity. Prevention and preparation for excessive hemorrhage is crucial for safe resection. Case Description: A 69-year-old woman presented with bitemporal hemianopsia and was found to have a sellar tumor with suprasellar extension, resembling a pituitary adenoma. Microscopic transsphenoidal resection was attempted but was interrupted by a massive intraoperative hemorrhage. Pathologic diagnosis was a spindle cell oncocytoma, and she was referred to our institution. She underwent preoperative embolization to decrease tumor vascularity, and resection was performed using a combined endoscopic endonasal and video-microscopic transcranial approach, using a 4K three-dimensional (3D) video microscope. The final diagnosis was a posterior pituitary tumor with immunopositivity for thyroid transcription factor-1, with preferred interpretation as a pituicytoma. Conclusions: A combined endonasal and transcranial approach with preoperative embolization is a useful strategy for hypervascular posterior pituitary tumors. A 4K 3D video microscope is compact, and it provides high-resolution images, contributing larger surgical space and facilitating a multi-team surgery.