动脉自旋标记技术在脑缺血影像诊断中的临床初步应用

目的评价动脉自旋标记技术(ASL)在慢性脑缺血灌注分析中的临床应用价值。方法健康志愿者5例,临床表现为慢性颈内动脉系统缺血症状的患者11例。使用3.0TMR成像系统对受试者除行常规MR平扫外,还行Q2TIPS的ASL扫描。观察所得相对局部脑血流量(rCBF)彩图有无灌注减低区,对灌注减低区采用注量变化程度来显示灌注变化的情况。结果在健康志愿者,ASL技术可清楚显示脑灰质、白质及深部核团的不同血流分布,灰质血流量明显高于白质。在11例颈内动脉系统脑缺血患者中3例临床表现为TIA的患者,其ASL灌注图显示双侧脑血流分布对称,无rCBF减低区,余8例患者共发现17个区域的rCBF较健侧明显减低。结论ASL可用于脑缺血患者的脑组织灌注评估。

Arterial Spin Labeling in the Cerebral Ischemia: A Preliminary Application

Objective To implement an arterial spin labeling (ASL) technique that is feasible in routine examinations and to evaluate the clinical application of the method for imaging blood flow in cerebral ischemia. Methods Five volunteers and twelve patients with the deficit symptom in relation to cerebral hemisphere were examined at a clinical 3. 0 T imaging unit (Magnetom Trio ;Siemens). 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 in the multisection mode was implemented, and MR routine examinations were also included. In regions of interest, maps of relative cerebral blood flow (CBF) were computed and analyzed. Results In the volunteers, different cerebral blood flows of gray and white matter determined with ASL were clearly observed. In the patients, ASL technique yielded the symmetrical normal perfusion values in 3 patients with TIA, and the lower values in the other 8 patients with seventeen hypoperfusion regions. Conclusion The ASL is a suitable method for assessment of ischemic perfusion.