Combination of Mn2+-Enhanced and Diffusion Tensor MR Imaging Gives Complementary Information About Injury and Regeneration in the Adult Rat Optic Nerve
Combination of Mn2+-Enhanced and Diffusion Tensor MR Imaging Gives Complementary Information About Injury and Regeneration in the Adult Rat Optic Nerve
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DOI：
10.1002/jmri.21606
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发表时间：
2009-01-01
影响因子：
4.4
通讯作者：
Brekken, Christian
中科院分区：
文献类型：
--
作者：
Thuen, Marte;Olsen, Oystein;Brekken, Christian
目的：评价锰（Mn 2+）增强MRI（MEMRI）和扩散张量成像（DTI）作为检测玻璃体内周围神经移植物（PNG）植入大鼠视神经（ON）后轴突损伤和再生的工具。材料和方法：在成年Fischer大鼠中，在ON挤压（ONC）、玻璃体内PNG、在损伤后0天和20天（dpl）玻璃体内注射MnCl 2（150 nmol）。MEMRI和回波平面137171（DTI-EPI）在玻璃体内注射MnCl 2后1天，以及在ONC、玻璃体内注射PNG和玻璃体内注射MnCl 2后0和20 dpl的1和21 dpl时获得。GAP-43免疫组化进行后，最后MRI。结果：ONC减少RGC密度在21 dpl的94%相比，非损伤ON无氯化锰注射。玻璃体内注射PNG和玻璃体内注射MnCl 2均改善了视网膜中RGC的存活率，其降低了90%。（ONC + MnCl2），82%（ONC + PNG），74%（ONC+PNG+ MnCl 2）与未损伤ON相比。DTI衍生参数[各向异性分数[FA]，平均扩散率，轴向扩散系数λ在1 dpl，CNRMEMRI和λ（1））的径向扩散率不受Mn 2+在ON中的存在的影响。（平行于）在损伤部位减少，而在21 dp 1，与在1 dp 1测量的值相比，它们在损伤部位增加。GAP-43免疫反应阳性轴突存在于ON远端的ONC injury situ.Conclusion：MEMRI和DTI使检测功能和结构退化后，大鼠ON损伤，并有相关性之间的MRI衍生和免疫组化测量轴突再生。
Purpose: To evaluate manganese (Mn2+)-enhanced MRI (MEMRI) and diffusion tensor imaging (DTI) as tools for detection of axonal injury and regeneration after intravitreal peripheral nerve graft (PNG) implantation in the rat optic nerve (ON).Materials and Methods: In adult Fischer rats, retinal ganglion cell (RGC) survival was evaluated in Flurogold (FG) back-filled retinal whole mounts after ON crush (ONC), intravitreal PNG, and intravitreal MnCl2 injection (150 nmol) at 0 and 20 days post lesion (dpl). MEMRI and echoplanar 137171 (DTI-EPI) was obtained of noninjured ON one day after intravitreal MnCl2 injection, and at 1 and 21 dpl after ONC, intravitreal PNG, and intravitreal MnCl2 injections given at 0 and 20 dpl. GAP-43 immunohistochemistry was performed after the last MRI.Results: ONC reduced RGC density in retina by 94% at 21 dpl compared to noninjured ON without MnCl2 injections. Both intravitreal PNG and intravitreal MnCl2 injections improved RGC survival in retina, which was reduced by 90% (ONC + MnCl2), 82% (ONC + PNG), and 74% (ONC+PNG+MnCl2) compared to noninjured ON. DTI-derived parameters [fractional anisotropy [FA], mean diffusivity, axial diffusivity lambda(parallel to) and radial diffusivity lambda(1)) were unaffected by the presence of Mn2+ in the ON. At 1 dpl, CNRMEMRI and lambda(parallel to) were reduced at the injury site, while at 21 dp1 they were increased at the injury site compared to values measured at I dpl. GAP-43 immunoreactive axons were present in the ON distal to the ONC injury site.Conclusion: MEMRI and DTI enabled detection of functional and structural degradation after rat ON injury, and there was correlation between the MRI-derived and immunohistochemical measures of axon regeneration.