目的　为内镜下行经鼻蝶入路视神经管减压术提供解剖学依据。 方法    选用12例成人尸颅标本，模拟内镜下经鼻蝶入路，观察视神经管及其周围结构。磨除视神经管，暴露并打开管内视神经鞘膜，观察鞘膜内视神经及眼动脉。  结果    视神经隆突是蝶窦内相对恒定的解剖标志，通过它可以确定视神经管眶口；眼动脉多走行于视神经的腹内侧，切开视神经鞘膜时应在外上壁进行。  结论    视神经隆突是重要的解剖标志；应在外上壁切开视神经鞘膜。

Objective　To provide anatomical  basis for performing the transsphenoidal endoscopic optic nerve decompression.　Methods　Twelve heads of adult cadavers were dissected under the operative endoscopy imitating the trassphnoidal approach to observe the optic canal and its surrounding structures. Then the optic canals were removed and sheath was exposed in order to observe the optic nerve and ophthalmic artery.     Results　Optic canal protuberance is a relatively consistent anatomical landmark in sphenoid sinus and the orbital aperture could be determined through the optic canal protuberance. Ophthalmic artery is always located in the ventromedial side of optic nerve and incision of sheath of optic nerve should be performed in the superolateral position.　Conclusions　Optic canal protuberance is an important anatomic landmark; incision of sheath of optic nerve should be performed in the the superolateral position.