摘要
目的对比研究动脉血质子自旋标记(ASL)与动态磁敏感对比(DSC)MRI 在急性脑缺血诊断中的应用价值。方法 27例发病3 d 内的急性脑卒中患者,均采用3.0 T MR 行脉冲式 ASL和 DSC MR 检查。观察2种技术的灌注表现,包括灌注不足、正常灌注、延迟灌注、过度灌注等,采用Mann-Whitney 检验做定性分析。在扩散加权成像显示的病变部位及对侧正常半球的镜像区域分别确定3个感兴趣区(ROI),测量信号强度并计算信号强度比(病侧/对照侧),并将结果做配对 t 检验。结果定性分析显示27例患者中,21例2种技术检查结果一致(灌注不足14例,正常灌注5例,过度灌注2例)。6例2种技术不一致,其中4例 ASL 显示灌注不足而 DSC 显示延迟灌注,2例 ASL 显示正常灌注而 DSC 显示延迟灌注,两者间差异无统计学意义(P>0.05)。定量分析示,2种技术的病侧与对照侧信号强度比值 ASL 为0.71±0.46,DSC 为0.73±0.42,两者间差异无统计学意义(P>0.05)。结论无创性 ASL 技术在检测灌注异常时与 DSC MRI 有相似的敏感性;ASL 可与常规MR 检查相结合,为临床诊断急性缺血性卒中提供有价值的信息。
Objective To compare an arterial spin labeling （ASL） technique with dynamic susceptibility contrast （DSC） MR imaging and evaluate the potential clinical role for this technique in patients with acute cerebral isehemia. Methods A second version of quantitative imaging of perfusion by using a single subtraction with addition of thin-section periodic saturation after inversion and a time delay （Q2TIPS） technique of pulsed ASL and DSC were both performed with a Magnetom Trio 3.0 T MRI system on 27 patients with acute isehemie stroke within 3 days of symptom onseL Perfusion deficits, normal perfusion, delayed perfusion and hyperfusion were observed and Mann-Whitney test was used for qualitative analysis. Quantitative analysis was performed using signal intensity measurements in three paired regions of interest （ROI） that was defined by diffusion-weighted imaging abnormalities and mirror regions in the eontralateral unaffected hemisphere respectively. Signal intensity ratios （infarcted region versus the unaffected eontralateral region） were calculated and compared using a paired t test （level of significance, P=0.05）. Results Qualitative analysis demonstrated agreement between the two techniques in 21 of 27 studies （ perfusion deficit, n = 14 patients ; normal perfusion, n = 5 ; and hyperfusion, n = 2 ）. In four studies, the two techniques disagreed when ASL demonstrated perfusion deficit and DSC demonstrated delayed perfusion. In other two studies, ASL was normal while DSC showed delayed perfusion. Both qualitative and quantitive analysis revealed there were no significant difference between the two techniques （ P 〉 0. 05 ）. Conclusions The noninvasive ASL technique was almost as sensitive as DSC MRI in detecting perfusion abnormalities. ASL can be combined with standard structural imaging within a single MRI examination and provide clinically meaningful information in the diagnosis of acute cerebral ischemic stroke.
出处
《中华放射学杂志》
CAS
CSCD
北大核心
2007年第11期1162-1165,共4页
Chinese Journal of Radiology
关键词
脑缺血
脑血管循环
磁共振成像
灌流
Brain ischemia
Cerebrovascular circulation
Magnetic resonance imaging
Perfusion
