Ueki Satoshi, Fujii Yukihiko, Matsuzawa Hitoshi, Takagi Mineo, Abe Haruki, Kwee Ingrid L, Nakada Tsutomu
Center for Integrated Human Brain Science, Brain Research Institute, University of Niigata, Niigata, Japan.
Am J Ophthalmol. 2006 Oct;142(4):591-6. doi: 10.1016/j.ajo.2006.05.042.
The effectiveness of diffusion trace value analysis for non-invasive assessment of retinal ganglion cell (RGC) axonal degeneration at multiple anatomic levels along the human visual pathway under clinical setting was evaluated.
Imaging study.
Ten patients with unilateral chronic optic neuropathy of varying cause and 16 age-matched normal subjects were studied. Trace, a tensor invariant that is considered to be a sensitive index for pathologic changes in axons, was analyzed at nine anatomic sites in each subject, namely, bilaterally at the level of the optic nerves, uncrossed chiasmal fibers, optic tracts and optic radiations, and crossed chiasmal fibers, using a 3.0 Tesla magnetic resonance imaging system.
Trace values of the optic nerve and uncrossed chiasmal fibers ipsilateral to the affected eye, the crossed chiasmal fibers, and optic tracts bilaterally were significantly higher than those of the corresponding anatomic sites in normal subjects. The optic nerve and uncrossed chiasmal fibers ipsilateral to the unaffected side and optic radiations, bilaterally, had trace values which were not significantly different from the values of the corresponding anatomic levels in normal subjects. The increase in trace value in the optic nerve and uncrossed chiasmal fibers ipsilateral to the affected side was greater than those of the crossed chiasmal fibers and optic tracts.
Findings are highly consistent with a degenerative process of RGC axons and trace values are quantitatively well correlated to predicted pathology at the given anatomical sites. Trace value measurement at multiple sites along fiber pathways appears to be a powerful addition to clinical assessment of the functionality of components of the visual pathways during various stages of a pathologic process.
评估在临床环境下，扩散轨迹值分析对沿人类视觉通路多个解剖层面的视网膜神经节细胞（RGC）轴突变性进行无创评估的有效性。
影像学研究。
对10例不同病因的单侧慢性视神经病变患者和16例年龄匹配的正常受试者进行研究。使用3.0特斯拉磁共振成像系统，在每个受试者的9个解剖部位分析轨迹值，轨迹值是一种张量不变量，被认为是轴突病理变化的敏感指标，这9个部位分别为双侧视神经水平、未交叉的视交叉纤维、视束和视辐射，以及交叉的视交叉纤维。
患侧眼睛同侧的视神经和未交叉视交叉纤维、交叉视交叉纤维以及双侧视束的轨迹值显著高于正常受试者相应解剖部位的轨迹值。未受影响侧同侧的视神经和未交叉视交叉纤维以及双侧视辐射的轨迹值与正常受试者相应解剖层面的值无显著差异。患侧同侧视神经和未交叉视交叉纤维的轨迹值增加幅度大于交叉视交叉纤维和视束。
研究结果与RGC轴突的退行性变过程高度一致，轨迹值与给定解剖部位的预测病理情况在数量上具有良好的相关性。沿纤维通路多个部位测量轨迹值似乎是病理过程各个阶段视觉通路组件功能临床评估的有力补充。
