视交叉前间隙有关结构的解剖观察及其临床意义

目的为经额入路行蝶鞍区手术提供外科解剖学依据。方法对30个经福尔马林固定的成年人尸头标本的视交叉前间隙及有关结构在肉眼和SXQ鄄Ⅱ型手术显微镜下进行观察,对视交叉前间隙的面积进行测算。结果①视交叉前间隙之间的面积为(28.4±6.2)mm2。两侧视神经颅内段越长,夹角越小,视交叉前间隙越大;两侧视神经颅内段越短,夹角越大,视交叉前间隙越小。②视交叉前缘至鞍结节之间的距离为(4.1±0.8)mm,两侧视神经于视交叉前之间的夹角为63.2°±5.8°。③颈内动脉自前床突内侧向上穿过硬脑膜之后,先向前、内、上方行至视神经下面,再弯向后、外、上方行于视神经外侧。④分布于视交叉上后面的视交叉上动脉来源于两侧大脑前动脉水平部段和前交通动脉。分布于视交叉下前面的视交叉下动脉来源于两侧颈内动脉和后交通动脉。结论经额入路蝶鞍区手术主要是通过视交叉前间隙,在颈内动脉之间的间隙操作,手术中应注意保护好视神经和视交叉的营养动脉,以减少并发症的发生。

Anatomic study on the structures in anterior space of optic chiasma and its clinical significance

Objective To provide the anatomic data of the sellar region f or transfrontal approach operation. Methods Under the operating microscope, the anterior space of optic chiasma and its neibouring structures were observed on 30 adult head specimens fixed by formalin. The area of the anterior space of opt ic chiasma were calculated as well. Results ①The area of anterior space of opt ic chiasma was (28.4±6.2)mm2. The longer the two sides of the intracranial port ion of optic nerve or the smaller the angle formed by the both sides of optic ne rves was, the bigger the area of the anterior space of optic chiasma was. Wherea s the shorter the two sides of the intracranial portion of optic nerve or the bi gger the angle formed by the both sides of optic nerves, the smaller the area of the anterior space of optic chiasma was. ②The distance between the anterior bo rder of optic chiasma and tuberculum sellae was (4.1±0.8)mm. The angle formed b y the both nerves was (63.2±5.8)° in front of optic chiasma. ③Having perforat ed the dura mater on the medial side of the anterior clinoid process, the intern al carotid artery first pass below the optic nerve with the course toward anteri or internall superior, and than curved to anterior external superior to the late ral of optic nerve. ④Optic chiasma superior artery, which was located in superi or posterior aspect of optic chiasma, came from the horizontal part of anterior cerebral artery and anterior communicating artery, while optic chiasma inferior artery, located in inferior anterior aspect of optic chiasma, originated from bo th internal carotid arteries and posterior communicating artery. Conclusions In order to reduce the postoperative complications, the nutrient arteries of optic nerve and optic chiasma must be protected during the sellar region for transfro ntal approach operation, for the operation mainly approach the anterior space of optic chiasma and performed between the two internal carotid arteries.