Rosso Charlotte, Hevia-Montiel Nidiyare, Deltour Sandrine, Bardinet Eric, Dormont Didier, Crozier Sophie, Baillet Sylvain, Samson Yves
AP-HP-Urgences Cérébro-Vasculaires, Laboratoire de Neurosciences Cognitives et Imagerie Cérébrale, and AP-HP-Service de Neuroradiologie, Université Pierre et Marie Curie, Paris, France.
Radiology. 2009 Jan;250(1):184-92. doi: 10.1148/radiol.2493080107. Epub 2008 Nov 18.
To compare predicted and final infarct lesion volumes determined by processing apparent diffusion coefficient (ADC) maps derived at admission diffusion-weighted (DW) magnetic resonance (MR) imaging in patients with acute stroke and to verify that predicted areas of infarct growth reflect at-risk penumbral regions based on recanalization status.
The French legislation waived the requirement for informed patient consent for the described research, which was based on patient medical files. However, patients and/or their relatives were informed that they could decline to participate in the research. Authors tested a semiautomated proprietary image analysis procedure in 98 patients with middle cerebral artery (MCA) stroke by modeling infarct growth on DW imaging-derived ADC maps. Predicted infarct growth (PIG) areas and predicted infarct volumes were correlated with final observed data. In addition, the effect of MCA recanalization on the correlation between predicted and observed infarct growth volumes was qualitatively assessed.
Predicted and final infarct volumes (rho = 0.828; 95% confidence interval [CI]: 0.753, 0.882; P < .0001) and infarct growth volumes (rho = 0.506; 95% CI: 0.342, 0.640; P < .0001) were significantly correlated. Visual comparative examination revealed satisfactory qualitative consistency between predicted and follow-up lesion masks. In patients without MCA recanalization, PIG did not differ significantly from final observed infarct growth (median PIG obtained with 0.93 ADC ratio cutoff [PIG(ratio)] of 27.1 cm(3) vs median infarct growth of 19.8 cm(3), P = .17). MCA recanalization revealed an overestimation of PIG (median PIG(ratio) of 24.8 cm(3) vs median infarct growth of 12 cm(3), P = .005), suggesting that the PIG area was part of ischemic penumbra.
Data show the feasibility of identifying at-risk ischemic tissue in patients with acute MCA stroke by using semiautomated analysis of ADC maps derived at DW imaging, without intravenous contrast material-enhanced perfusion-weighted imaging.
比较急性卒中患者入院时扩散加权磁共振成像（DW-MRI）所获得的表观扩散系数（ADC）图经处理后得出的梗死灶预测体积与最终体积，并验证梗死灶生长的预测区域是否根据再通状态反映了缺血半暗带区域。
法国法律免除了对本研究（基于患者病历）患者知情同意的要求。然而，患者和/或其亲属被告知他们可以拒绝参与研究。作者通过在DW成像衍生的ADC图上模拟梗死灶生长，对98例大脑中动脉（MCA）卒中患者测试了一种半自动专有图像分析程序。预测梗死灶生长（PIG）区域和预测梗死灶体积与最终观察数据相关。此外，定性评估了MCA再通对预测和观察到的梗死灶生长体积之间相关性的影响。
预测梗死灶体积与最终梗死灶体积（rho = 0.828；95%置信区间[CI]：0.753，0.882；P <.0001）以及梗死灶生长体积（rho = 0.506；95%CI：0.342，0.640；P <.0001）显著相关。视觉对比检查显示预测病变与随访病变掩膜之间在定性上具有令人满意的一致性。在未发生MCA再通的患者中，PIG与最终观察到的梗死灶生长无显著差异（ADC比率截断值为0.93时获得的PIG中位数[PIG(比率)]为27.1 cm³，而梗死灶生长中位数为19.8 cm³，P = 0.17）。MCA再通显示PIG被高估（PIG(比率)中位数为24.8 cm³，而梗死灶生长中位数为12 cm³，P = 0.005），提示PIG区域是缺血半暗带的一部分。
数据表明，在未使用静脉注射对比剂增强灌注加权成像的情况下，通过对DW成像获得的ADC图进行半自动分析来识别急性MCA卒中患者的缺血风险组织是可行的。
