Extended Endoscopic Endonasal Approach To The Clivus Region: Related Study

Objective: the aim of study is to describe the endoscopic anatomical landmarks to theclivus region by extended endoscopic endonasal approach; compare to the microscopicalexposure and size of clivus region treated with transpetrosal presigmoid approach,and theaim of study is further to discuss the merit of the approach.Material:10cadaveric specimens, fixed frame, microscope, neural navigation system,the microscopic instruments kits, nerve endoscopy, endoscopic surgical instruments package,drill grinding system, lighting system, camera system, conventional surgical instruments,vernier caliper, compass, protractor, digital camera, etc.Mehtods: Experiments made up of two groups,neural endoscopic group andmicroscopical group, five cadaveric specimens in a group, which were marked the CCDcenter of the clivus region through the neuronavigation system. The neural endoscopic groupwas divided three phases, nanal phase, clival phase and dural phase, and we observed theanatomical landmarks in every phase,mesured the related data in dural phase. Themicroscopical group was divided three phases,phase of the flap, phase of the bone flap anddural phase. We observed the anatomical landmarks in every phase,mesured the related datain dural phase,and compared to the neural endoscopic group.Results: The anatomical landmarks was nasal septum,tuberculum pharyngeum,sphenoidosculum and pterygoid canal treated with the extended endoscopic endonasal approach.Theexposed area of clivus is all clival region and vicinage through the neuroendoscopy, and theregion is486.09±62.30mm2. The exposed area of clivus is the upper and middle clival regionthrough the microscope, and the region is431.06±40.30mm2.Conclusions： The extended endoscopic endonasal approach could provide wideoperative field and be considered a minimally invasive technique to approach the clivusregion. The nasal septum and pharyngeal tubercle are important anatomic landmarks. The extended endoscopic endonasal approach for recstion of tumors in clivus region have shortpath, small trauma, rapid recovery and short hospitalizing time. Meanwhile, it existscranioplasty and leakage of cerebrospinal fluid.