增强型准连续动脉自旋标记灌注成像技术对重度颅内粥样硬化性狭窄低灌注定量测量

摘要

Objective To acquire cerebral blood flow ( CBF) in patients with severe intracranial ather-osclerotic stenosis with enhanced pseudo-continuous arterial spin labeling ( e-pCASL ) and compare it with the findings of dynamic susceptibility contrast-enhanced perfusion-weighted imaging ( DSC PWI) and pseudo-continu-ous arterial spin labeling ( pCASL) . Methods A total of 39 consecutive patients with severe intracranial ather- osclerotic stenosis were enrolled in this study. All these patients underwent e-pCASL, pCASL, and DSC PWI. Blood supply territory of the stenosed artery was outlined as region of interest ( ROI) and a mirror ROI was ap-plied. Ratios of CBF were calculated as value of ROI/value of mirror ROI. SNK variance analysis was conducted to compare the CBF values of three persufion methods. Factorial analysis of variance and Pearson were employed to analysis the difference and the correlation of e-pCASL CBF ratio, pCASL CBF ratio, and DSC PWI relative cerebral blood flow ( rCBF) ratio. Results The e-pCASL CBF ratio, pCASL CBF ratio, and DSC PWI rCBF ratio were not significantly different ( P=0. 476 ) . TTP showed the CBF ratios were not significantly different be-tween the healthy side and diseased side in patients with severe intracranial atherosclerotic stenosis. ATT showed the correlations of pCASL CBF ratio and DSC PWI rCBF ratio were not affected by ATT. Conclusions e-pCASL with multiple-post labeling delay time and pCASL have good consistency with DSC PWI in the quantitative meas-urement of hypoperfusion pattern. As an accurate, simple, non-invasive, and repeatable technique, e-pCASL has good correlation with DSC PWI in the quantitative measurement of hypoperfusion pattern that is not affected by ATT.%目的：采用多参数增强型准连续式动脉自旋标记动脉成像( e-pCASL)获取颅内动脉粥样硬化性狭窄患者脑血流量(CBF)图，并与传统动态磁敏感增强灌注成像(DSC PWI)及准连续式动脉自旋标记灌注成像(pCASL)进行比较，使用DSC PWI为金标准，对比3种灌注方式测量CBF比值的差异性与相关性。方法纳入重度颅内动脉粥样硬化性狭窄患者39例，同时行e-pCASL、 pCASL和 DSC PWI成像，根据狭窄动脉责任供血区域，经验性手工勾勒感兴趣区进行测量，获得CBF值，使用镜像法获得对侧CBF比值，对3种灌注方式的CBF比值进行SNK方差分析。同时基于e-pCASL获取动脉通过时间(ATT)，基于DSC PWI获取最大达峰时间(TTP)。使用ATT和TTP 进行分层分析，对e-pCASL CBF比值、 pCASL CBF比值与DSC PWI 相对脑血流量(rCBF)比值进行析因方差分析和相关性分析。结果 e-pCASL CBF比值及pCASL CBF比值与DSC PWI rCBF比值一致性良好(P=0．476)。使用TTP分层数据显示， TTP及灌注方法的选择在重度动脉狭窄患者患侧与健侧的CBF比值中差异无统计学意义。根据ATT分组显示， e-pCASL CBF与DSC PWI rCBF比值的相关性不随ATT时间改变而变化。结论 e-pCASL和pCASL在重度动脉狭窄患者中与DSC PWI 在CBF定量测量中一致性良好，且e-pCASL与DSC PWI相关性不受ATT因素变化的影响，具有准确、简便、无创、可重复性好的特点。