Hypoxic brain damage : MR imaging findings and its correlation with histological findings

我们研究了缺氧脑病的顺序磁共振成像结果，并将其与尸检的组织学结果相关联。我们回顾性地回顾了6例缺氧脑损伤患者的连续磁共振成像研究。在重复的MR图像上评估信号强度和大脑形态特征的顺序变化。另外两例尸检患者的MR结果提示皮质层状坏死，MR结果与组织学结果相关。使用1.5 t Magnetom H15扫描仪（Siemens, Erlangen, Germany）和头部线圈进行MR成像。在轴向平面上获得脉冲序列为500/15（重复时间[TR] msec/回波时间msec）的t1加权自旋回波图像和长TR自旋回波（2500/15,90）图像，矩阵为256^<**>256，切片厚度为5-10-mm，视场为20-25 cm。偶尔，获得额外的冠状或矢状图像。MR影像学表现的时间演变…More被任意分为以下形态学阶段：急性期，发病后1周内；亚急性早期，第11-19天；亚急性晚期，第21 ~ 28天；慢性阶段，41天以后。顶枕颞叶皮层的分水岭区受累最为频繁。急性期可见脑水肿。增强t1加权图像显示亚急性早期皮质层状强化；未增强的t1加权图像显示亚急性晚期特征性层状高信号病变。这两种表现在组织学上反映了皮质层状坏死。然而，我们无法在组织学检查中阐明导致t1加权图像层流高强度的原因。在慢性期，可见皮质萎缩和延迟但进行性白质改变。缺氧脑损伤的MR影像学特征变化复杂但明显。皮层层状坏死和迟发性白质变性可见。少

We investigated sequential MR imaging findings of hypoxic encephalopathy and correlated them with histological findings at autopsy. We retrospectively reviewed sequential MR imaging studies of the brain in 6 patients with hypoxic brain damage. Sequential changes in signal intensity and morphological features of the brain were evaluated on repeated MR images. In the other two autopsied patientnts who had MR findings suggestive of cortical laminar necrosis, MR findings were correlated with histological findings. MR imaging was performed with a 1.5-T Magnetom H15 scanner (Siemens, Erlangen, Germany) with a head coil. T1-weighted spin-echo images, with a pulse sequence of 500/15 (repetition time [TR] msec/echo time msec) and long TR spin-echo (2500/15,90) images were obtained in the axial plane, with a 256^<**>256 matrix, a 5-10-mm section thickness, and a field of view of 20-25 cm. Occasionally, additional coronal or sagittal images were obtined. Temporal evolution of MR imaging findings … More was arbitrarily divided into frou morphological stages : acute stage, within 1 week after the onset ; early subacute stage, days 11-19 ; late subacute stage, days 21-28 ; and chronic stage, days 41 onward.Involvement of the watershed zones in the parietooccipitotemporal cortex was most frequent. Cerebral edema was seen in the acute stage. Enhanced T1-weighted images showed cortical laminar enhancement in the early subacute stage ; unenhanced T1-weighted images revealed characteristic laminar hyperintense lesions in the late subacute stage. Both of these findings reflected cortical laminar necrosis at histology. However, we could not elucidate at histological examination what caused the laminar hyperintensity on T1-weighted images. In the chronic stage, cortical atrophy and delayd but progressive white matter changes were seen. Changes in MR imaging features of hypoxic brain damage are complex but distinct. Cortical laminar necrosis and delayd white matter degeneration can be delineated. Less