From the Calgary Stroke Program, Department of Clinical Neurosciences (S.H.A., C.D.d'E., E.M.Q., M.N., M.D.H., M.G., A.M.D., B.K.M.), Department of Radiology (C.D.d'E., M.D.H., M.G., A.M.D., T.Y.L., B.K.M.), Department of Community Health Sciences (M.D.H.), and Seaman Family MR Center (S.H.A., C.D.d'E., E.M.Q., M.N., M.G., A.M.D., B.K.M.), University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute (M.D.H., M.G., A.M.D., B.K.M.); Department of Neurology, Chosun University School of Medicine, Gwang Ju, South Korea (S.H.A.); Department of Neurology, Hospital Vall d'Hebron, Ps. Vall d'Hebron, Barcelona, Spain (M.R.); Department of Neurosciences and Rehabilitation, University Hospital, Ferrara, Italy (E.F.); and Lawson Health Research Institute and Robarts Research Institute, London, Ontario, Canada (T.Y.L.).
Stroke. 2015 Apr;46(4):968-75. doi: 10.1161/STROKEAHA.114.008648. Epub 2015 Feb 19.
Thrombolysis depends on the ability of blood and thrombolytic agents to permeate thrombus. We devised a novel technique to quantify blood permeating through thrombi and determine whether this parameter predicts early recanalization with intravenous tissue-type plasminogen activator.
Intravenous tissue-type plasminogen activator-treated patients with stroke and complete occlusion on computed tomographic angiography were analyzed using perfusion computed tomography and a delay insensitive algorithm. We generated maps that measure delay in arrival time of contrast within the intracranial arterial tree (T0 maps). A positive sloped regression line of T0 values measured along artery silhouette distal to thrombus was defined as marker of permeable thrombus (occult anterograde flow). Median T0 values at proximal and distal thrombus interface were measured. Early recanalization was assessed on first angiography of subsequent intra-arterial procedure or on a 4-hour computed tomographic angiography.
Of 66 patients, occult anterograde flow was detected in 17 (25.8%). Early recanalization was more in patients with occult anterograde flow versus not (66.7 versus 29.7%; P=0.031). Median T0 value (in s) at distal thrombus interface (1.5 versus 3.8; P=0.006) and difference in median T0 value between proximal and distal thrombus interface (1.3 versus 3.7; P=0.014) were less in early recanalizers versus in nonrecanalizers. In multivariable analysis, patients with occult anterograde flow and T0 value difference between proximal and distal thrombus interface ≤2 s recanalized most (71.4%; odds ratio, 12.15; 95% confidence interval, 2.05-71.91), whereas patients with retrograde flow and T0 value difference >2 s recanalized least (25.9%; odds ratio, 1).
Occult anterograde flow through thrombus can be assessed by perfusion computed tomography T0 maps and predicts early recanalization with intravenous tissue-type plasminogen activator robustly.
溶栓依赖于血液和溶栓剂渗透血栓的能力。我们设计了一种新的技术来量化血液渗透血栓的程度，并确定该参数是否可以预测静脉注射组织型纤溶酶原激活剂（tissue-type plasminogen activator，tPA）早期再通。
对接受静脉注射 tPA 治疗的卒中和 CT 血管造影（computed tomographic angiography，CTA）完全闭塞的患者进行灌注 CT 检查和延迟不敏感算法分析。我们生成了颅内动脉树内对比剂到达时间延迟（time to arrival，T0）图，测量血栓远端动脉轮廓上 T0 值的正斜率回归线，定义为可渗透血栓的标志物（隐匿性顺行血流）。测量近端和远端血栓界面处的 T0 值。早期再通通过随后的动脉内介入治疗的首次血管造影或 4 小时 CTA 进行评估。
66 例患者中，17 例（25.8%）检测到隐匿性顺行血流。隐匿性顺行血流组的早期再通率高于无隐匿性顺行血流组（66.7% vs. 29.7%；P=0.031）。远端血栓界面处的中位 T0 值（以秒为单位）（1.5 秒 vs. 3.8 秒；P=0.006）和近端与远端血栓界面处 T0 值差值（1.3 秒 vs. 3.7 秒；P=0.014）在早期再通者中均小于非再通者。多变量分析显示，隐匿性顺行血流且近端与远端血栓界面 T0 值差值≤2 s 的患者再通率最高（71.4%；优势比，12.15；95%置信区间，2.05-71.91），而逆行血流且 T0 值差值>2 s 的患者再通率最低（25.9%；优势比，1）。
通过灌注 CT T0 图可以评估血栓内的隐匿性顺行血流，并且可以很好地预测静脉注射 tPA 的早期再通。
