Probability of cortical infarction predicted by flumazenil binding and diffusion-weighted imaging signal intensity - A comparative positron emission tomography/magnetic resonance Imaging study in early ischemic stroke
Probability of cortical infarction predicted by flumazenil binding and diffusion-weighted imaging signal intensity - A comparative positron emission tomography/magnetic resonance Imaging study in early ischemic stroke
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DOI：
10.1161/01.str.0000134746.93535.9b
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发表时间：
2004-08-01
期刊：
影响因子：
8.3
通讯作者：
Lackner, K
中科院分区：
文献类型：
--
作者：
Heiss, WD;Sobesky, J;Lackner, K
背景和目的——区分可逆性缺血性损伤和不可逆性缺血性损伤对于识别可能受益于治疗干预的急性缺血性缺陷患者至关重要。弥散加权成像（DWI）已成为检测缺血性病变的首选方法。中枢苯二氮卓受体配体 11C 氟马西尼 (FMZ) 的正电子发射断层扫描 (PET) 已被证明是神经元完整性的可靠标记。比较这 2 个成像参数在早期缺血性中风中预测皮质梗死的概率。方法 - 在 12 名急性中风患者中，将 DWI（中位值，症状出现后 6.5 小时）和 FMZ-PET（间隔，DWI 和 PET 之间的时间间隔为 85 分钟）的结果与中风发作后 24 至 48 小时 T2 加权磁共振成像 (T2-MRI) 上的梗死范围进行比较。使用各自的 DWI、FMZ 和后来分类为代表梗塞或非梗塞组织的感兴趣体素 (VOI) 的表观扩散系数 (ADC) 值来计算预测最终梗塞的概率曲线。结果 - 预测皮质梗塞的 95% 的限值是通过相对 FMZ 结合（小于或等于 3.2）、DWI 信号强度（大于或等于 1.18）和 ADC 值（小于或等于0.83）。值超出 95% 限制的皮质区域不一定与最终皮质梗塞体积重叠，也不一定完全一致。这些区域各自的中位体积为 FMZ 中位 10.9，范围为 0 至 99.7 cm(3)； DWI 中位数 15.2，范围 0 至 116.0 cm(3)； ADC 中位数 12.4，范围 0 至 112.7 cm(3)；最终梗死中位数为 14.9，范围为 0 至 114.7 cm(3)。总体而言，平均而言，83.5% 的最终梗塞是通过 FMZ 结合减少来预测的，84.7% 是通过 DWI 信号强度增加来预测的，70.9% 是通过降低 ADC 值来预测的。早期调查中未预测到的最终梗塞部分（假阴性）分别为：FMZ 为 4.8 cm(3)（中位数）、DWI 为 3.7 cm(3)、ADC 为 6.0 cm3。未包含在最终梗塞中的假阳性体积为 FMZ 0 cm(3)（中位数）、DWI 5.1 cm(3) 和 ADC 3.6 cm(3)。结论 - 这些结果表明 FMZ-PET 和 DWI 在预测缺血性皮质梗死概率方面具有可比性，但 FMZ-PET 的假阳性预测概率较低。最终的梗塞包括这些成像方式未识别的组织；在研究时，这些组织区室是可行的并且可以从治疗中受益。预测概率的差异可能与测量变量的根本差异有关：苯二氮卓受体活性是皮层神经元完整性的可靠标志，而细胞外空间中水分子的运动可能是组织损伤的更可变的指标。
Background and Purpose-The differentiation of reversible from irreversible ischemic damage is essential for identifying patients with acute ischemic deficits who may benefit from therapeutic interventions. Diffusion-weighted imaging (DWI) has become the method of choice to detect ischemic lesions. Positron emission tomography ( PET) of the central benzodiazepine receptor ligand 11C flumazenil (FMZ) has been shown to be a reliable marker of neuronal integrity. These 2 imaging parameters were compared with respect to the probability to predict cortical infarction in early ischemic stroke.Methods-In 12 patients with acute stroke, results from DWI (median, 6.5 hours after symptom onset) and FMZ-PET (interval, 85 minutes between DWI and PET) were compared with infarct extension 24 to 48 hours after onset of stroke on T2-weighted magnetic resonance imaging (T2-MRI). Probability curves predictive of eventual infarction were computed using respective DWI, FMZ, and apparent diffusion coefficient ( ADC) values for voxels of interest (VOI) later classified as representing infarcted or noninfarcted tissue.Results-Ninety-five percent limits predictive of cortical infarction were determined for relative FMZ binding (less than or equal to3.2), DWI signal intensity (greater than or equal to1.18), and ADC values (less than or equal to0.83). Cortical regions with values beyond these 95% limits did not necessarily overlap with nor were fully congruous with final cortical infarct volumes. The respective median volumes for these regions were FMZ median 10.9, range 0 to 99.7 cm(3); DWI median 15.2, range 0 to 116.0 cm(3); ADC median 12.4, range 0 to 112.7 cm(3); and final infarct median 14.9, range 0 to 114.7 cm(3). Overall, 83.5% of the final infarct, on average, was predicted by decreased FMZ binding, 84.7% by increased DWI signal intensity, and 70.9% by a decreased ADC value. The portions of the final infarct not predicted in the early investigation (false-negatives) were 4.8 cm(3) ( median) for FMZ, 3.7 cm(3) for DWI, and 6.0 cm3 for ADC. The false-positive volumes not included in the final infarct were 0 cm(3) (median) for FMZ, 5.1 cm(3) for DWI, and 3.6 cm(3) for ADC.Conclusions-These results indicate that FMZ-PET and DWI are comparable in the prediction of probability of ischemic cortical infarction, but FMZ-PET carries a lower probability of false-positive prediction. The final infarcts include tissue not identified by these imaging modalities; at the time of the study, these tissue compartments are viable and could benefit from treatment. The discrepancy in predictive probability could be related to the fundamental difference of the measured variables: benzodiazepine receptor activity is a reliable marker of neuronal integrity in the cortex, and movement of water molecules in the extracellular space might be a more variable indicator of tissue damage.