展神经MRI与塑化薄层断面解剖学研究

A comparative study on sectional anatomy of the abducent nerve with MRI and plastination

目的 对展神经进行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展神经横断面、矢状面和冠状面各 1例的薄层切片 ,同时采用快速小角度激发三维成像 (FLASH 3D)序列完成头颅标本及 6 0例正常人脑干MR扫描 ,对展神经脑池段及Dorello管的形态、走行进行对比观察。结果 展神经及Dorello管的行程、解剖结构能够准确显示 ,塑化切片与MRI有良好的对应关系 ;展神经在桥前池内向前上外侧走行 ,与脑干背侧连线夹角 12 7 2 0°± 8 16°,5 0岁以上年龄组夹角较小 ,与 30岁以下年龄组之间差异有显著性意义 (t=1 80 0 ,P <0 0 5 ) ;展神经与脑正中矢状面的夹角左右分别为 32 6 7°± 9 17°、31 87°± 11 18° ,左右侧差异无显著性意义 (t =1 990 ,P >0 0 5 )。结论 薄层MRI能够准确显示神经脑池段及Dorello管的解剖结构 。

Objective To obtain the normal image and sectional anatomical data of the abducent nerve with MRI and plastination. Methods The plastination slices of the nerves were made in 3 individuals (1 transverse, 1 sagittal, and 1 coronal). Meanwhile, 60 volunteers and 3 specimens of the skull were scanned with FLASH-3D sequence. The course and morphology of the nerve and Dorello′s canal were observed from the plastination slices, the MR images, and MPR images. Results MRI well revealed the structure and morphology of the abducent nerve and Dorello′s canal, and had the similar result corresponding to the plastination section. The abducent nerve passed through the prepontine cistern superiorly, anteriorly, and laterally, and formed an angle of 127.20°±8.16°with the posterior plane of the brain stem. The angle was smaller in individuals over 50 years old, and there was marked difference between individuals under 30 and over 50 years old(t=1.800,P<0.05). The angle between the abducent nerve and the median sagittal plane of the brain was 32.67°±9.17°on the left and 31.87°±11.18°on the right, and there was no marked difference in the angle among them(t=1.990,P>0.05). Conclusion Thin-slice MRI can demonstrate the anatomic structure of the nerve and Dorello′s canal accurately, it is a better imaging technique for determination of the abducent nerve and its related structures.