The transsellar approach is adequate for removal of lateral tumor compartment in the majority of cases with laterally extended pituitary neuroendocrine tumors. The tumor compartments dorsal and ventral to the horizontal portion of the intracavernous carotid artery are amenable to the removal. But for removal of the tumor compartment lateral to the carotid siphon requires additional use of the parasellar approach ¹⁾.

see Endoscopic transsphenoidal approach