动脉自旋标记MRI脑血流灌注成像在亚临床期肝性脑病患者的研究

The study of arterial spin labeling perfusion MR imaging in the patients with subclinical hepatic encephalopathy

目的用动脉自旋标记(ASL)MRI灌注成像技术评价亚临床肝性脑病(SHE)患者基底节区的脑血流灌注模式。方法对16例经神经心理试验诊断为SHE的患者和13例年龄和教育程度相匹配的健康志愿者进行MRI平扫和ASL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流量(CBF),并以同侧额叶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均高于对照组:CBF值右侧分别为0.88±0.17,1.01±0.06,0.96±0.13和0.93±0.10,左侧分别0.91±0.15,1.00±0.07,0.94±0.12和0.97±0.11,志愿者相应部位CBF值右侧分别为0.81±0.04,0.95±0.04,0.88±0.04和0.90±0.04,左侧分别为0.81±0.02,0.94±0.04,0.87±0.05和0.92±0.04。结论 ASL脑血流灌注成像探测到SHE患者基底节区的脑血流灌注是增加的。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。

Objective To investigate the hemodynamic changes in brain basal ganglia in patients with subclinical hepatic encephalopathy （SHE） using arterial spin labeling （ASL） MRI perfusion technique. Methods 16 patients with SHE diag- nosed by neuropsychologic tests and 13 cases education-matched healthy volunteers accepted examinations on 1. 5 T GE MR scanner. The scanning protocol included anatomical images and ASL perfusion MR imaging. Using the function tool perfusion software, the parameter maps of cerebral blood flow （CBF） was created. Bilateral head of caudate nucleus, glo- bus pallidus, putamen, thalamus were selected as regions of interest （ROD. Ipsilateral white matter of frontal lobe was used as reference, the ratios of ROI were calculated and compared with those in the control group. Results The CBF ratio for every ROI was higher in SHE patients versus the control. CBF value of right head of caudate nucleus, globus paIlidus, putamen, thalamus versus ipsilateral white matter in frontal lobe in SHE patients was 0.88±0.17, 1.01±0.06, 0.96± 0.13 and 0. 93±0.10, respectively, CBF value of left ROI was 0.91±0.15, 1.00±0.07, 0.94＋0.12 and 0. 97±0.11, respectively; and CBF value of right ROI in control group was 0.81±0.04, 0.95±0.04, 0.88±0.04 and 0. 90± 0. 04 , respectively, CBF value of left ROI in control was 0. 81±0.02, 0.94±0.04, 0. 87±0. 05 and 0. 92±0.04, respectively. Conclusion The increasing CBF in basal ganglia could be identified in patients with SHE using ASL MRI perfusion tech- nique. CBF increase was compatible with the opinion that the cerebral blood flow redistributed from cortical areas to basal ganglion structures.