Endoscopic Transnasal Approach To Cranio-vertebral Junction: An Applied Anatomy Study

【Objective】Endoscopic transnasal approach to cranio-vertebral junction surgery on cadaveric head has been performed in this study to detect the exposure of this approach and finally resect the odontoid process.Removed clivus bone to expose the underlayer structures.Some important landmarks involved in this approach were measured.【Materials and Methods】45 dried skull base specimens and five sets of atlas and axis (sex and age are undetermined.) were selected to observe corresponding areas and obtain some anatomical measurements involved in this approach.4 Han adult human fresh cadaveric heads(male 3,female 1,age undetermined) had been operated by a pure endoscopic trannasal approach.【Results】Enodoscopic endonasal approach can definitely expose from lower clivus superiorly to axis inferiorly.Odontoid process has been successfully resceted on each specimen.Remove clivus to expose the underlayer structures from pons-medulla groove to medllua is available.Odontoidectomy can impact the stability of cranio-vertebral junction which needs a anterior or posterior internal fixation.【Conclusion】Odontoidectomy can be successfully completed by a pure endoscopic endonasal approach.Vertebral artery do not add risks to this manipulation.Drill lower clivus can expose the pons-medulla groove and V4 segment vertebral artery.So some disease in this area can probably be handled by this approach.