Endoscopic endonasal transsphnoid approaches to the medial wall of cavernous sinus:a microsurgical and endoscopic anatomic study

Objective To study the microanatomical nature of the medial wall of cavernous sinus,we compared various endoscopic transsphenoidal approaches using cadaveric specimens to develop endoscopic endonasal surgical approaches to the cavernous sinus.Methods Ten injected adult cadaveric heads were studied,2 were cut longitudinally and were studied with microscope,8 were operated with endoscopes.The extent of the surgical exposure to the cavernous sinus,the skewed endoscopic anatomic view,and the maneuverability of surgical instruments were studied after various endoscopic endonasal approaches via one or two nostril.Results The cavernous sinus could be exposed clearly by using endoscopy.The internal carotid artery,oculomotor,trochlera,abducent and optic nerves could be separated completely.Sphenoidal sinus is the most important structure in these approaches.The common and certain anatomic landmark in the posterior bony wall of sellar-type sphenoidal sinus is clival indentation,which is the landmark to identify the sellar floor and other structures.A wide view of the medial wall of carcenous sinus can be obtained through angled scopes.Conclusions The approach of exposing cavernous sinus visa transsphenoisal by using endoscopic endonasal is simple,minimally invasive,and useful for clinic operation.