【摘要】 目的用MR灌注成像技术评价亚临床肝性脑病(SHE)患者的脑血流灌注模式。方法对12例经神经心理试验诊断为SHE的患者和10例年龄和教育程度相匹配的健康志愿者进行MR平扫和灌注成像,分别测量双侧尾状核头、苍白球、壳核、丘脑和额叶白质的脑血容量(CBV)、脑血流量(CBF)和平均通过时间(MTT),并以同侧额叶脑白质作为参照进行统计分析。结果SHE患者各感兴趣区与白质的比值:CBV值分别是1.32±0.25、1.19±0.46、1.51±0.20、1.69±0.53;CBF值分别为1.64±0.50、1.61±0.65、2.06±0.61、2.23±0.75;MTT值分别是0.83±0.17、0.76±0.20、0.78±0.19、0.78±0.17。志愿者相应部位CBV值为1.32±0.33、1.02±0.29、1.44±0.37、1.66±0.57;CBF值为1.36±0.24、1.08±0.28、1.55±0.51、1.58±0.64;MTT值为0.95±0.18、0.91±0.19、0.93±0.15、0.93±0.13。SHE患者较正常组MTT明显缩短,双侧丘脑、右侧尾状核头达到统计学意义的降低(P<0.05);CBF明显升高,左侧苍白球达到统计学意义的升高(P<0.05);CBV无明显变化。结论SHE患者基底节区灌注增加是血流从皮质到基底节区的重新分布,这是对运动前区、运动区功能缺陷及注意力缺陷的代偿反应,与皮质-基底节-丘脑-皮质环路密切相关。更多还原

【Abstract】 Objective To investigate the perfusion pattern of the brain in patients with subclinical hepatic encephalopathy(SHE)by using MRI perfusion technique.Methods Twelve patients with SHE diagnosed by neuropsychologic tests and 10 age and education-matched healthy volunteers accepted examinations on a 1.5 T MR scanner.The scanning protocol included conventional brain scan and dynamic susceptibility contrast enhanced perfusion MR imaging.Using the MGH perfusion software,the parameter maps of cerebral blood flow(CBF),cerebral blood volume(CBV)and mean transit time(MTT)were created.Bilateral head of caudate nucleus,globus pallidus,putamen,thalamus were selected as regions of interest(ROI),and ipsilateral white matter of frontal lobe was used as a reference.The ratios(ROI versus ipsilateral white matter in frontal lobe)in patient group were calculated and compared with those in the control group.Results In SHE group,CBV ratio of head of caudate nucleus,globus pallidus,putamen,thalamus was 1.32±0.25,1.19±0.46,1.51±0.20,and 1.69±0.53,respectively,CBF ratio was 1.64±0.50,1.61±0.65,2.06±0.61,and 2.23±0.75,respectively,and MTT ratio was 0.83±0.17,0.76±0.20,0.78±0.19,and 0.78±0.17,respectively.CBV ratio in control group was 1.32±0.33,1.02±0.29,1.44±0.37,and 1.66±0.57,respectively,CBF ratio was 1.36±0.24,1.08±0.28,1.55±0.51,and 1.58±0.64,respectively,and MTT ratio was 0.95±0.18,0.91±0.19,0.93±0.15,and 0.93±0.13,respectively.CBF increased in SHE group compared with that in control group,and statistical increase can be detected in left globus pallidus(P<0.05).MTT reduced in SHE group,and statistical reduction can be detected in bilateral thalamus and right head of caudate nucleus(P<0.05).CBV had no statistical change in SHE patients.Conclusion The increasing CBF and decreasing MTT in basal ganglion and thalamus could be identified in patients with SHE.CBF increase was compatible with the opinion that the cerebral blood flow redistributed from cortical areas to basal ganglion structures.It was the result of a compensatory response of functional deficits and complex attentional deficits in premotor and motor regions.It had close relationship with the multiple parallel loops from cortex through basal ganglion and back to cortex.更多还原