What structures lie within the transsphenoidal surgical field?

What structures lie within the transsphenoidal surgical field?

The sella turcica, within the body of the sphenoid, pro-vides bony protection for the pituitary gland. The diaphragma sella is a roof of dura pierced by the pituitary stalk with its arachnoid, which extends to the hypothala-mus. The cavernous sinus surrounds the walls of the sella and contains the cavernous portion of the internal carotid artery as well as cranial nerves III, IV, and VI. The optic nerves converge above the diaphragm to form the chiasm. Arterial bleeding during transsphenoidal hypophysectomy may be from the carotid artery or its branches and venous bleeding arises from the cavernous sinus. If excessive bleed-ing from the cavernous sinus occurs, it may be difficult to control. Temporary or permanent packing of the sinus may be necessary.