Department of Neurology and Neurological Sciences, Stanford Stroke Center, Palo Alto, Calif 94304, USA.
Stroke. 2010 Aug;41(8):1665-72. doi: 10.1161/STROKEAHA.110.582452. Epub 2010 Jul 1.
Diffusion-weighted magnetic resonance imaging of the brain is a promising technique to help predict functional outcome in comatose survivors of cardiac arrest. We aimed to evaluate prospectively the temporal-spatial profile of brain apparent diffusion coefficient changes in comatose survivors during the first 8 days after cardiac arrest.
Apparent diffusion coefficient values were measured by 2 independent and blinded investigators in predefined brain regions in 18 good- and 15 poor-outcome patients with 38 brain magnetic resonance imaging scans and were compared with those of 14 normal controls. The same brain regions were also assessed qualitatively by 2 other independent and blinded investigators.
In poor-outcome patients, cortical structures, in particular the occipital and temporal lobes, and the putamen exhibited the most profound apparent diffusion coefficient reductions, which were noted as early as 1.5 days and reached a nadir between 3 and 5 days after the arrest. Conversely, when compared with normal controls, good-outcome patients exhibited increased diffusivity, in particular in the hippocampus, temporal and occipital lobes, and corona radiata. By qualitative magnetic resonance imaging readings, 1 or more cortical gray matter structures were judged to be moderately to severely abnormal in all poor-outcome patients except for the 3 patients imaged within 24 hours after the arrest.
Brain diffusion-weighted imaging changes in comatose, postcardiac arrest survivors in the first week after the arrest are region and time dependent and differ between good- and poor-outcome patients. With increasing use of magnetic resonance imaging in this context, it is important to be aware of these relations.
脑弥散加权磁共振成像技术是一种很有前途的方法，可以帮助预测心脏骤停后昏迷幸存者的功能预后。我们旨在前瞻性评估心脏骤停后昏迷幸存者在第 1 天至第 8 天大脑表观弥散系数变化的时空特征。
通过 2 名独立且盲法的研究人员在 18 名预后良好和 15 名预后不良的患者的 38 次脑磁共振成像扫描中，在预先设定的脑区测量表观弥散系数值，并与 14 名正常对照者的测量值进行比较。另外 2 名独立且盲法的研究人员还对同一脑区进行了定性评估。
在预后不良的患者中，皮质结构，特别是枕叶和颞叶以及壳核，表现出最明显的表观弥散系数降低，在发病后 1.5 天即可观察到，在发病后 3 至 5 天达到最低值。相反，与正常对照组相比，预后良好的患者表现出更高的弥散性，特别是在海马体、颞叶和枕叶以及放射冠。通过定性磁共振成像阅读，除了发病后 24 小时内成像的 3 名患者外，所有预后不良的患者的 1 个或多个皮质灰质结构均被判断为中度至重度异常。
心脏骤停后昏迷幸存者在发病后第 1 周的脑弥散加权成像变化与部位和时间有关，并且在预后良好和不良的患者之间存在差异。在这种情况下，随着磁共振成像的广泛应用，了解这些关系非常重要。
