Grandin Cécile B, Duprez Thierry P, Smith Anne M, Oppenheim Catherine, Peeters André, Robert Annie R, Cosnard Guy
Department of Medical Imaging, MRI Section, Cliniques Universitaires St Luc, Université Catholique de Louvain, 10 Avenue Hippocrate, B-1200 Brussels, Belgium.
Radiology. 2002 May;223(2):361-70. doi: 10.1148/radiol.2232010673.
To compare predictors of infarct growth in hyperacute stroke from a retrospective review of various relative and quantitative parameters calculated at perfusion-weighted magnetic resonance (MR) imaging performed within 6 hours after ictus.
Fluid-attenuated inversion recovery and diffusion- and perfusion-weighted images were obtained in 66 patients. The initial infarct was delineated on diffusion-weighted images; the hemodynamic disturbance, on apparent mean transit time (MTT) maps; and the final infarct, on follow-up fluid-attenuated inversion recovery images. Relative (without and with deconvolution) and quantitative values of the bolus arrival time, time to peak (TTP), apparent MTT or MTT, cerebral blood volume (CBV), peak height, and cerebral blood flow (CBF) index or CBF were calculated for initial infarct, infarct growth (final minus initial infarct contour), viable hemodynamic disturbance (apparent MTT minus final infarct contour), and contralateral mirror regions. Univariate and multivariate analyses (receiver operating characteristic curves and discriminant analysis) were performed to compare the diagnostic performance of these parameters for predicting infarct growth.
At univariate analysis, relative peak height and quantitative CBF were the best predictors of infarct growth; at multivariate analysis, a function of peak height and TTP for relative measurements and CBF alone for quantitative measurements. Quantitative and relative measurements (without or with deconvolution) worked equally well. A combined relative peak height or TTP threshold (<54% or >5.2 seconds, respectively) had a sensitivity of 71% and a specificity of 98%. A quantitative CBF threshold (<35 mL/min/100 g) had a sensitivity of 69% and a specificity of 85%.
A combination of relative peak height and TTP measurements allowed the best prediction of infarct growth, which obviates more complex quantitative calculation.
通过回顾性分析在发病6小时内进行的灌注加权磁共振成像（MRI）所计算出的各种相对参数和定量参数，比较超急性卒中梗死灶扩大的预测指标。
对66例患者进行了液体衰减反转恢复序列、扩散加权成像和灌注加权成像检查。在扩散加权图像上勾勒出初始梗死灶；在表观平均通过时间（MTT）图上确定血流动力学紊乱情况；在随访的液体衰减反转恢复图像上确定最终梗死灶。计算初始梗死灶、梗死灶扩大（最终梗死灶轮廓减去初始梗死灶轮廓）、存活血流动力学紊乱（表观MTT减去最终梗死灶轮廓）以及对侧镜像区域的团注到达时间、达峰时间（TTP）、表观MTT或MTT、脑血容量（CBV）、峰值高度以及脑血流量（CBF）指数或CBF的相对值（有无去卷积）和定量值。进行单因素和多因素分析（受试者操作特征曲线和判别分析）以比较这些参数预测梗死灶扩大的诊断性能。
单因素分析时，相对峰值高度和定量CBF是梗死灶扩大的最佳预测指标；多因素分析时，相对测量为峰值高度和TTP的函数，定量测量为单独的CBF。定量测量和相对测量（有无去卷积）效果相同。相对峰值高度或TTP联合阈值（分别<54%或>5.2秒）的敏感性为71%，特异性为98%。定量CBF阈值（<35 mL/min/100 g）的敏感性为69%，特异性为85%。
相对峰值高度和TTP测量相结合能对梗死灶扩大做出最佳预测，无需进行更复杂的定量计算。
