猪脑出血动态弥散加权成像和血肿周围组织质子波谱分析

Serial diffusion-weighted MR imaging and 1H-MRS around hematoma in pigs with frontal lobe hemorrhage

目的 :阐明脑出血 1～ 7d时血肿周围水肿的演变规律和性质 .方法 :将 15只质量 10～ 15kg的仔猪动脉血 2 .5mL注入右侧额叶 ,在 2 4h(n =15 ) ,72h(n=9)和 7d(n =5 )后用1.5TMR行FLAIR(液体衰减返转恢复快速自旋回波序列 ) ,DWI(弥散加权成像 )和血肿周围组织的1 H MRS(质子波谱分析 ) ;病理观察 4只动物 2 4h时血肿周围组织对伊文思蓝的外渗以确定血脑屏障的完整性 ,同时对各时间点处死动物的脑组织进行常规病理观察 .结果 :FLAIR显示 2 4h至 7d时血肿周围组织水肿严重 ,局部平均表观弥散系数 (ADC)升高 ,2 4h时灶周大量伊文思蓝外渗 ,但水肿区1 H MRS分析除 1例大量出血者外均无乳酸峰 .结论 :中等量脑出血时血肿周围以血管源性脑水肿为主 ,并未发现缺血性损害 ,但不排除大量出血时存在缺血性损害的可能性 .

AIM: To determine the characteristics of perilesion edema during 1-7 days in pigs with intracerebral hemorrhage (ICH). METHODS: With injection of 2.5 mL autologous artery blood into right frontal lobes, 15 pigs (10-15 kg) had fluid-attenuated inversion-recovery (FLAIR), diffusion weighted imaging (DWI) and 1H-magnetic resonance spectrum ( 1H-MRS) by 1.5 T MR at 24 hours (n=15), at 72 hours (n= 9) and on day 7 (n=5). In 4 animals, blood-brain barrier permeability was observed by leakage of Evan’s blue at 24 hours (n= 4). RESULTS: The edema was located around hematoma on the sequence of FLAIR at 24 hours after ICH. The perilesional apparent diffusion coefficiency (ADC) increased and no lactic acid peak was observed by 1H-MRS from 24 hours to day 7 in all the animals but one. CONCLUSION: During 1-7 days after ICH, the vasogenic edema dominates around the hematoma. Only in case of massive hemorrhage, ischemia may coexist.