鞍侧腔颅神经鞘的发育及其显微解剖研究

Embryological and Anatomical Study on Sheaths of Cranial Nerve in Lateral Sellar Compartment

目的研究鞍侧腔外侧壁和穿行颅神经鞘结构,为此区手术提供解剖学基础。方法采用45例胚胎标本和10例成人尸颅标本,对鞍侧腔行组织学连续切片和显微解剖观察。结果胚胎14周后鞍侧腔外侧壁发育形成二层结构,外层由脑膜层组成,内层由基质纤维包绕第Ⅲ、Ⅳ、Ⅵ和Ⅴ1颅神经复合体组成;脑膜鞘伴随动眼神经和滑车神经,进入鞍侧腔直至前床突区,但其远侧端仅有周围神经鞘包裹。Meckel腔止于三叉神经节后份,三叉神经分支仅有周围神经鞘包裹。脑膜鞘内的蛛网膜颗粒可能是鞍区脑膜瘤的来源之一。结论了解鞍侧腔外侧壁膜结构及其与颅神经鞘的关系,以利于术中保护颅神经功能。

Objective To study the lateral wall of lateral sellar compartment (LSC) and the sheaths of cranial nerves running through it in order to provide an anatomical basis for operative approaches involving the sellar region. Methods Serial histological sections of 45 human fetuses of well determined ages,as well as dissections under opera- tive microscopy in 10 adults were performed to observe the development and organization of the contents of the LSC. Results The later wall of LSC in the 14 to 19 week-old fetus have two components just as in the adult. The superfacial layer of the lateral wall of LSC is formed by dense organization of meningeal cells, and the deep layer is composed of mesenchymal cells around the oculomotor, trochlear and ophthalmic nerve complex. The oculomotor and the trochlear nerve possess meningeal sheaths which accompany the nerves into the LSC up to the anterior clinoid processs for the oculomotor nerve. The meninges of Meckels cave stop at the trigeminal ganglion, its branches and the remaining distal portion of the oculomotor and the trochlear nerve have only peripheral sheaths. The presence of arachnoid granulations into the LSC, around the trigeminal ganglion and near the oculomotor and the trochlear nerve may be one of the original of meningiomas in these areas. Conclusion Familiarity with the relationship between the structures of the lateral wall of LSC and the meningeal sheaths of cranial nerves is beneficial to the surgeon to preserve the uninvolved cranial nerve during operation.