Eustachian Tube as a Landmark to the Internal Carotid Artery in Endoscopic Skull Base Surgery

Objective The purpose of this study was to probe the relationship between the eustachian tube and the internal carotid artery in skull base surgery by an intranasal endoscopic approach. Study Design Cadaver study and illustrative cases. Setting Minimally invasive surgery laboratory and operating room. Subjects and Methods A series of 5 cadaveric heads were dissected to elaborate on the relevant surgical anatomy about the eustachian tube and the internal carotid artery. Three cases were presented to illustrate the application of our laboratory findings. Results The bony-cartilaginous junction of the eustachian tube was just anterior to the first genu of the internal carotid artery by an intranasal endoscopic approach. The 3 patients in our study tolerated the procedure well and experienced no serious complications after surgery. Conclusions The anatomic data and clinical cases in this study confirmed that the eustachian tube is a consistent and reliable landmark to the internal carotid artery to avoid its injury in skull base surgery through the endoscopic endonasal route.