兔全脑梗死的质子磁共振波谱实验研究

An experimental research of global ischemic infarction by using proton magnetic resonance spectroscopy

目的:观察兔全脑梗死的质子磁共振波谱(1H-MRS)改变,探讨全脑梗死后脑内代谢物Naa、Cr、Cho和Lac的动态演变规律。方法:12只新西兰大白兔麻醉后,立即断头,然后将兔头用不透气的塑料薄膜紧密包裹,并用37°C水垫包裹、棉被保温。采用Marconi1.5T磁共振成像系统和小关节表面线圈,分别在模型建立前及建立后0.5h、1h、2h、4h、6h、8h、12h和24h进行MRS检查。结果:全脑梗死后24h内Cho含量无明显变化。Lac在斩首后0.5h内迅速达到高峰,但0.5h～24h在高水平保持相对稳定。Naa和Cr含量于全脑梗死后呈线性持续下降。结论:1H-MRS能无创性地检测在体全脑梗死后脑代谢物的改变。

Objective: To observe the evolution of global infarction in rabbits on proton magnetic resonance spectroscopy ( 1H-MRS), and explore the dynamic evolvement process of the metabolite, such as Naa、Cr、Cho and Lac within the globally infarct brain tissue. Methods: 12 New Zealand rabbits underwent decapitation after anesthesia, then the heads were kept warm by using a 37 C water chamber. 1H-MRS research was performed on a Marconi 1.5T MRI system. 1H-MRS were performed before operation as well as at 0.5h, 1h, 2h, 4h, 6h, 8h, 12h and 24h after operation. Results: Cho level did not change obviously after global infarction. Lac rose to high level at 0.5h, and remained steady relatively in the high level from 0.5h to 24h after decapitation. Naa and Cr level decreased linearly and continuously after global ischemia. Conclusion: 1H-MRS could noninvasively detect the dynamic evolvement process of the metabolite within the global infarct brain tissue.