[Expanded Endoscopic Endonasal Surgery for Skull Base Tumors].

With the development of endoscopic and surgical instruments, expanded endoscopic endonasal surgery for skull base tumors has been widely performed. Compared with conventional microscopic transsphenoidal surgery, endoscopic surgery provides a wider view and clearer images, owing to the introduction of a high-resolution camera. However, for safe and reliable surgery, it is necessary to create an appropriate surgical field and avoid complications. This article discusses the basic knowledge needed for expanded endoscopic endonasal surgery, focusing on surgical anatomy and techniques and how to close the skull base completely.