Yenari M A, Beaulieu C, Steinberg G K, Moseley M E
Department of Neurology, Stanford Stroke Center, Stanford University Medical Center, CA, USA.
J Neuroimaging. 1997 Oct;7(4):227-31. doi: 10.1111/jon199774227.
Diffusion-weighted magnetic resonance imaging (MRI) can detect ischemia within minutes of onset, but its ability to reliably detect hyperacute cerebral hemorrhage is unknown. The present study characterized diffusion-weighted, T2-weighted, and contrast-enhanced T1-weighted MRI appearances of hemorrhagic transformation within 5 hours of onset in experimental embolic stroke. Apparent diffusion coefficients and MRI signal characteristics were noted within corresponding regions of hemorrhage observed on gross pathology. Apparent diffusion coefficients were significantly increased within hemorrhagic lesions, but were still within the expected range for bland ischemia. The appearance of the hemorrhagic lesions on diffusion-weighted MRI was also very heterogeneous and not very useful for clinical screening. Other MRI modalities should be investigated, but computed tomography remains the only widely available clinical method of reliably detecting cerebral hemorrhage.
扩散加权磁共振成像（MRI）能够在发病数分钟内检测到缺血情况，但其可靠检测超急性脑出血的能力尚不清楚。本研究对实验性栓塞性卒中发病5小时内出血转化的扩散加权、T2加权及对比增强T1加权MRI表现进行了特征描述。在大体病理观察到的出血相应区域记录表观扩散系数及MRI信号特征。出血性病变内的表观扩散系数显著升高，但仍在单纯性缺血的预期范围内。出血性病变在扩散加权MRI上的表现也非常不均一，对临床筛查用处不大。应研究其他MRI检查方式，但计算机断层扫描仍是可靠检测脑出血的唯一广泛可用的临床方法。
