Long-Delay Arterial Spin Labeling Provides More Accurate Cerebral Blood Flow Measurements in Moyamoya Patients: A Simultaneous Positron Emission Tomography/MRI Study.
Long-Delay Arterial Spin Labeling Provides More Accurate Cerebral Blood Flow Measurements in Moyamoya Patients: A Simultaneous Positron Emission Tomography/MRI Study.
复制标题
长期延迟的动脉自旋标记可在Moyamoya患者中提供更准确的脑血流量测量：同时进行正电子发射断层扫描/MRI研究。
DOI：
10.1161/strokeaha.117.017773
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发表时间：
2017-09
期刊：
影响因子：
8.3
通讯作者：
Zaharchuk G
中科院分区：
文献类型：
--
作者：
Fan AP;Guo J;Khalighi MM;Gulaka PK;Shen B;Park JH;Gandhi H;Holley D;Rutledge O;Singh P;Haywood T;Steinberg GK;Chin FT;Zaharchuk G
动脉自旋标记(ASL)MRI是一种有前景的无创脑血流成像技术，但难以用于侧支循环异常、动脉传输时间长的脑血管病人。要在临床上采用，ASL必须首先根据这些具有挑战性的患者病例的参考标准进行优化和验证。我们比较了15例Moyamoya患者的标准延迟ASL(标记后延迟=2.025秒)、多延迟ASL(标记后延迟=0.7秒-3.0秒)和长标记长延迟ASL采集(标记后延迟=4.0秒)与同步的[15O]正电子发射断层扫描脑血流图。对每个患者进行动态敏感性对比，以确定轻度、中度和严重的最大时间延迟(Tmax)区域。将20个皮质区域每次ASL扫描的相对CBF测量值与PET参考标准进行比较，并计算中、重度Tmax延迟区域的相关性。标准延迟ASL在Tmax延迟严重的区域低估了相对脑血流量20%，特别是在通常受烟雾病影响的前区和中区(P<；0.001)。通过多延迟采集校正动脉传输时间可改善与PET的一致性，但在传输延迟较长的情况下仍低估了CBF(P=0.02)。长标记长延迟ASL扫描显示与PET的相关性最强，平均相对CBF在不同模式之间没有差异，即使在严重延迟的区域也是如此。标签后延迟时间为≥4秒是必要的，并且可以与多延迟策略相结合，以对烟雾病患者的脑血流进行稳健的ASL评估。
Arterial spin labeling (ASL) MRI is a promising, noninvasive technique to image cerebral blood flow (CBF) but is difficult to use in cerebrovascular patients with abnormal, long arterial transit times through collateral pathways. To be clinically adopted, ASL must first be optimized and validated against a reference standard in these challenging patient cases. We compared standard-delay ASL (post-label delay=2.025 seconds), multidelay ASL (post-label delay=0.7–3.0 seconds), and long-label long-delay ASL acquisitions (post-label delay=4.0 seconds) against simultaneous [15O]-positron emission tomography (PET) CBF maps in 15 Moyamoya patients on a hybrid PET/MRI scanner. Dynamic susceptibility contrast was performed in each patient to identify areas of mild, moderate, and severe time-to-maximum (Tmax) delays. Relative CBF measurements by each ASL scan in 20 cortical regions were compared with the PET reference standard, and correlations were calculated for areas with moderate and severe Tmax delays. Standard-delay ASL underestimated relative CBF by 20% in areas of severe Tmax delays, particularly in anterior and middle territories commonly affected by Moyamoya disease (P<0.001). Arterial transit times correction by multidelay acquisitions led to improved consistency with PET, but still underestimated CBF in the presence of long transit delays (P=0.02). Long-label long-delay ASL scans showed the strongest correlation relative to PET, and there was no difference in mean relative CBF between the modalities, even in areas of severe delays. Post-label delay times of ≥4 seconds are needed and may be combined with multidelay strategies for robust ASL assessment of CBF in Moyamoya disease.