急性脑硬塞MRI增强表现

目的：探讨早期急性脑梗塞ＭＲＩ增强表现。材料和方法：３１例早期急性脑梗塞，其中大脑半球区梗塞２２例，脑干梗塞９例。所有病例均为出现临床症状后３天内进行ＭＲＩ非增强扫描及增强扫描。结果：出现异常强化征象的脑梗塞有１９例（１９／３１）。其中１８例为大脑半球区梗塞（１８／２２），１例为脑干梗塞（１／９）。这一异常强化具体表现为大脑皮层的曲线状血管内强化（大脑半球区脑梗塞）和点状血管内强化（脑干梗塞）。大脑半球区脑梗塞异常强化的分布特点为：这些异常血管内强化均位于大脑皮层，且这些皮层血管的近端强化最为明显，远端强化逐渐减弱直至消失。而１例脑干梗塞血管内强化代表了椎～基底动脉。结论：异常血管内强化为大脑半球区梗塞早期增强表现。而脑干梗塞缺少这一征象，即使有血管内强化也为一种不可靠的辅助征象。

Contrast-Enhanced MRI Findings in Acute Cerebral Infarction

Purpose: To evaluate the contrast-enhanced MRI findings in early acute cerebral infarction. Materials and Methods: 31 patients with acute cerebral infarction, including 22 patients with cortical cerebral infarction and 9 with brainstem infarction. were all examined with MRI within 3 days after onset. Results: Abnormal enhancement signs were seen in 19 of 31 infarcts, 18 of which were cortical infarction and 1 of which was a brainstem infarction. The sign manifested as curvilinear intravascular enhancement in cortical cerebral infarction andnoddar intravascular enhancement in brainstem infarction. Contrast enhancement of vessels(intravascular enhancement sign)appeared most intense in the proximal portions gradully diminishing in the more distal portions of these vessels and finally disappeared. The sign of the only brainstem infarction appeared in the ajacent basilar artery. Conclusion: This abnomally intravascular enhancement sign is characterized of acute cortical cerebral infarction. But brainstem infarction lacks this sign, if any, that is incredible.