三叉神经脑池段MRI与塑化薄层切片对照研究

Comparison on sectional anatomy of intracisternal segment of trigeminal nerve with MRI and plastination

目的 对三叉神经脑池段进行MRI与塑化切片对照研究 ,获得正常影像和断层解剖资料。方法 采用生物塑化技术制作三叉神经横断位 8例、矢状位和冠状位各 1例薄层切片 ,同时采用FLASH 3D序列完成头颅标本及 60例正常人脑干MR扫描 ,对三叉神经脑池段的形态、走行进行对比观察。结果 标本及活体MR扫描 ,三叉神经脑池段的行程、解剖结构能够准确显示 ,塑化切片与MRI有良好的对应关系。多平面重建 (Multiplanarreconstruction ,MPR)横断位上三叉神经脑池段长度 (12 .78± 2 .0 3 )mm ,向前上外侧走行 ,与脑干背侧连线成角 (10 3 .0 4± 5 .14 )° ,随着年龄的增大 ,三叉神经脑池段与脑干背侧连线的夹角逐渐变小 ,其中小于3 0岁年龄组与 5 0岁以上年龄组之间有显著性差异 (P <0 .0 5 ) ;左右侧三叉神经与脑正中矢状面的夹角分别为 (9.2 8± 4.80 )° ,(9.44± 4.2 0 )° ,(P >0 .0 5 ) ,无显著性差异。结论 薄层MRI能够准确显示神经脑池段的解剖结构和走行规律 ,是评价三叉神经及相关结构的准确的影像学技术。

Objective To obtain the normal image and sectional anatomical data of the intracisternal segment of the trigeminal nerve with MRI and plastination. Methods The plastination slices of the nerves were made in 10 individuals (8 from transversal view, 1 sagittal and 1 coronal view). Meanwhile, 60 volunteers and 3 specimens of the skull were scanned with FLASH 3D sequence. The course and morphology of the nerve were observed through the plastination slices, and the MR images and multiplanar reconstruction (MPR) images. Results MRI revealed the structure and morphology of the intracisternal segment of the trigeminal nerve very well, and obtained the similar results as by the plastination section. MPR transversal image showed that the length of the intracisternal segment of the trigeminal nerve was (12.78±2.03) mm, forming an angle of (103.04±5.14)°with the posterior plane of the brain stem. With the increase of age, the angle became gradually smaller, and there was a significance in individuals under 30 and over 50 years old ( P <0.05). The angle between the trigeminal nerve and the median sagittal plane of the brain was (9.28±4.80)°on the left and (9.44±4.20)° on the right, no marked difference in the angle among the different groups( P >0.05). Conclusion Thin slice MRI can demonstrate the anantomic structure and the course of the intracisternal segment accurately, so it is the better imaging technique for determination of the trigeminal nerve and its related structures.