摘要
目的:探讨实验性急性脑梗塞弥散加权MRI表现的病理基础。材料和方法:新西兰白兔27 只制成急性自身动脉血栓性脑梗塞动物模型,用弥散加权(DW)和T2 WMRI技术于0 .5 ～48h 行系列扫描。计算病灶和对照侧不同时间的表观弥散系数(ADC) ,并与光镜和电镜对照分析。结果:栓塞后梗塞核心ADC 逐渐降低,在6 ～12h 达最低点,以后逐渐回升;对应病理改变为细胞内水肿逐渐加重到细胞破裂、血管源性水肿出现,至组织坏死液化。T2 WI仅能显示血管源性水肿出现后的梗塞灶。结论:DWMRI敏感反映了脑缺血病理生理学演变过程,有助于确定梗塞后细胞的损伤程度。
Purpose: To study the pathologic basis of diffusion weighted MR imaging findings on experimental acute cerebral infarction. Materials and Methods: Acute cerebral infarction models were made in twenty seven New Zealand white rabbits by injecting autologous arterial clot fragments. The models were serially scanned with DW and T 2W MR imaging from 0.5 to 48 hours after embolization. Apparent diffusion coefficients (ADC) of ischemia region and contrast region were calculated and correlated with light and electron microscopic findings. Results: The ADC measured in the infarction core gradually decreased to the lowest point in 6～12 hours and then rose gradually. The corresponding sequential pathologic changes were gradual increase of intracellular edema, then rupturing of cells, emergence of vasogenic edema, and final necrosis and liquefaction. T 2Wl showed the infarction lesions only after emergence of vasogenic edema. Conclusion: DW MRI sensitively reflects the pathophysiologic evolution of cerebral ischemia, so it may be helpful for ascertaining the extent of cellular damage after stroke.
出处
《中国医学影像学杂志》
CSCD
1999年第4期278-281,共4页
Chinese Journal of Medical Imaging
关键词
脑梗塞
弥散成像
NMR
成像
cerebral ischemia, magnetic resonance imaging
diffusion imaging
animal experiment
