Microanatomic study of anterior and posterior clinoidectomy

Objective To quantitatively assess the microanatomic exposure of anterior and posterior clinoidectomy on a cadaver model by using a neuronavigation system and explore it's application.Methods Four cadaveric heads(Eight sides) injected with colored latex were used.Simulate pterional craniotomy were performed,and then anterior and posterior clinoid were drilled step by step.A frameless stereotactic navigation device was used to measure the ex-posure of optic nerve,internal carotid artery,basilar artery,the optic-carotid window and the carotid-oculomotor win-dow.The differences of exposure between before and after clinoidectomy were compared.Results After anterior clinoidectomy,the exposed length of optic nerve and carotid artery increased(11.4±1.8) mm and(3.9±2.1) mm,re-spectively;and the exposed width of the optic-carotid window,anterior and posterior carotid-oculomotor window in-creased(7.1±1.7) mm,(2.6±0.9) mm and(3.5±1.6) mm,respectively.After posterior clinoidectomy,the exposed len-gth of basilar artery increased(2.8±1.5) mm.There were significant differences were observed between before and after clinoidectomy( 0.05).Conclusions Clinoidectomy can increase the exposure of optic nerve,internal ca-rotid artery,basilar artery,the optic-carotid window and the carotid-oculomotor window;and it can be applied to les-ions located in paraclinoid,parasella,cavernous sinu and upper basilar artery.