三叉神经颅内段横断层解剖与MRI

Sectional Anatomy and MRI of Trigeminal Nerve

目的：探讨三叉神经颅内段在横断面上的解剖学特征，为三叉神经病变的影像学诊断提供形态学依据。方法：在36例成尸头部连续横断层标本与10例自愿者的3D—CISS序列头部横断层图像上，观察三叉神经的走行、位置及毗邻关系。结果：在经小脑中脚的横断面上，三叉神经脑池段连于小脑中脚，经脑桥小脑角池上份行向前外侧，走行于脑桥基底部外侧与小脑幕之间；在经海绵窦的横断面上，三叉神经节在海绵窦后部外侧，发出眼神经，向前穿人海绵窦外侧壁，经眶上裂入眶；在经颈动脉管的横断面上，三叉神经节发出的上颌神经和下颌神经，夹在蝶骨体与颞叶断面之间，后方为颞骨岩部；在经卵圆孔的横断面上，蝶骨大翼上有卵圆孔和棘孔，分别有下颌神经和脑膜中动脉通过。头部MRI横断层扫描对三叉神经的辨认与连续横断层标本具有较好的对应性。结论：颅脑横断层标本结合MRI显示三叉神经具有优势，可清楚地显示三叉神经脑池段、神经节段、颅底段的走行、位置及毗邻关系。

Objective：To investigate the anatomical characteristics of the trigeminal nerve on the trans- verse plane in order to provide morphological basis for the imaging diagnosis of the trigeminal lesions. Methods ： The morphology and adjacent relationships of trigeminal nerve were studied through comparing the horizon- tal serial sections of 36 adult cadaver brains with 3D - CISS MR images of 10 healthy subjects. Results：On the cross section through middle cerebcllar peduncle, the cisternal segment of trigeminal nerve linked to middle cer- ebellar peduncles and ran to the anterolateral side in the upper part of the pontocerebellar cistern between the basilar part of pans and the tentorium of cerebellum; On the cross section through the cavernous sinus, the tri- geminal ganglion was located in the posterolateral part of the cavernous sinus and sent out ophthalmic nerve which entered the orbital cavity by the superior orbital fissure after passing through the lateral wall of cavernous sinus; On the cross section through carotid canal, trigeminal ganglion sent out maxillary nerve and mandibular nerve, which was in the rear of petrous bone, clips between the section of sphenoid body and temporal lobe; On the cross section through foramen oval, there were foramen oval and foramen spinosum on the greater wing of sphenoid bone through which the mandibular nerve and the middle meningeal artery passed respectively. The i- dentification of the trigeminal nerve on the transverse MRI scanning was corresponding with the horizontal sectional specimen. Conclusions：The serial transverse sectional specimens combining with 3D - CISS MRI has ad- vantages on displaying the course, morphology and adjacent relationships of the cisternal segment, the ganglion segment and the skull base segment of the trigeminal nerve.