Abstract
Pituitary adenomas are a common lesion of the skull base that can invade the cavernous sinus. The invasion of the cavernous sinus leads to difficulty removing these tumors and is an independent risk factor for subtotal resection and recurrence. The mainstay of surgical treatment for pituitary adenomas with cavernous sinus invasion is an endoscopic endonasal approach for resection, sometimes with extended approaches, radiation, medical treatment, or open craniotomies. An algorithm for the best treatment for pituitary adenomas with invasion into the cavernous sinus can be complex and must account for the anatomic extensions of the mass with relation to the internal carotid artery and surrounding neurovascular structures. Therefore, this chapter aims to review the current standard of care in addressing pituitary tumors with cavernous sinus invasion using expanded endoscopic endonasal approaches (EEA) with particular references to surgical anatomy and nuances of the endoscopic pituitary surgery. Original cadaveric dissections and illustrative cases are presented to detail our current surgical technique allied with tailored adjuvant therapies. Treatment strategies are further discussed based on tumor findings. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022