**9.1 Transsphenoidal approach**

It is an extra-arachnoidal direct route to pituitary gland. It has the advantage of avoiding brain retraction, early optic nerves decompression with minimal manipulation, and wide operative view. Posterior wall of sphenoidal sinus, or sellar floor, can be accessed via a transnasal or translabial route. Usually, it involves the usage of microscope, endoscope, or both. Whether endoscope or microscope is used, the procedure has three-stages that are needed to reach the intrasellar space: nasal stage, sphenoidal stage, and sellar stage.

It is important to utilize an operative setup that is comfortable for whole team. Patient is typically positioned supine with 20-degrees head elevation and is positioned straight or slightly extended and fixed using Mayfield head clamp. The surgeon usually operates on the right and facing of the patient. We prefer to have the scrub nurse on the right side of the surgeon and the assistant on the left side. The screen and the navigation are positioned on the left side of the patient facing the surgeon (**Figure 10**). Neuronavigation is essential for dealing with tumors that extended to supra- or para-sellar regions, and recurrent tumors.
