大脑中动脉供血区脑缺血后同侧丘脑继发性损害的MR实验研究

本文应用磁共振(magnetic resonance,MR)成像在体观察大脑中动脉(middle cerebral artery,MCA)供血区脑缺血后同侧丘脑的信号变化。结果显示:(1)通过MRA(magnetic resonance angiography)可以观测到单侧MCA的闭塞与血流再通,而供应丘脑的大脑后动脉信号无变化;(2)脑缺血后1d MR T2WI(T2weighted imaging)显示单侧MCA供血区原发病灶呈高信号,3d、7d时此原发病灶信号增高程度有所降低,至14d信号强度再次明显增高;(3)脑缺血后1d和3d时双侧丘脑T2信号无差别,7d和14d时脑缺血同侧丘脑T2信号减低,T2值降低;(4)MCA供血区脑缺血后原发病灶和同侧丘脑T2值的变化不同步。上述结果证实MR能够在活体显示MCA供血区脑缺血后同侧丘脑的继发性损害。

The MR experimental study of the secondary damage in ipsilateral thalamus following focal cerebral ischemia in middle cerebral artery territory

The objective of present study is to observe magnetic resonance (MR) changes in ipsilateral thalamus following focal cerebral ischemia in middle cerebral artery (MCA) territory. The results showed: (1) Magnetic resonance angiography (MRA) could validate the occlusion and recirculation of the MCA, but the signal of ipsilateral posterior cerebral artery which supply blood for thalamus in MRA was no change; (2) On 1d after cerebral ischemia, the MR T2 weighted imaging (MR T2WI) showed high signal intensity in the middle cerebral artery territory. The high signal of primary lesion lowered slightly on 3 d and 7 d, and the second peak was seen on 14 d; (3) No changes were detected in the thalamus on 1 d and 3 d. On 7 d and 14 d, the T2 signal decreased in the thalamus ipsilateral to the occluded MCA; (4) The trend of the T2 value changes of primary lesion and ipsilateral thalamus were not in-phase. These results confirm that MR can image the secondary damage in the ipsilateral thalamus after focal cerebral ischemia of single side MCA territory in vivo.