MAGNETIZATION TRANSFER DURING RAT CEREBRAL ISCHEMIA

描述：这是一项关于进一步发展 研究人员的磁化传递技术及其在大鼠上的应用 大脑中动脉阻塞(MCAO)模型。常规磁共振成像 已知在早期检测中不敏感和非特异性 缺血事件和新的弥散加权成像(DWI)方法 似乎在缺血的早期阶段表现出敏感性，但不是 一定要在以后的阶段。已经开发出一种脉冲技术，即 能够测量绑定和之间的正向磁化传输率 自由质子(KF)具有良好的精确度。初步结果表明， 在缺血期期间和之后KF的显著下降； 造影剂在再灌注时似乎是不可逆的，并与 已知的细胞损伤区域。建议对时间和时间进行测量 永久性大脑中动脉闭塞大鼠KF的空间分布特征 假设KF的减少将与细胞损伤有关 正如组织病理学所见。发作后血压升高之间的联系 T2和KF的降低也将在相同的大鼠模型中进行研究 检验T2和KF的共同分布可以分段的假设 提供有关缺血细胞损伤的信息，特别是 组织水分的增加会导致T2的增加和同时的 KF的降低。

DESCRIPTION: This is a proposal for the further development of the investigator's magnetization transfer technique with application to the rat model of middle cerebral artery occlusion (MCAO). Conventional MR imaging is known to be insensitive and nonspecific in the detection of early ischemic events, and the newer diffusion-weighted imaging (DWI) method appears to show sensitivity at the earlier stages of ischemia but not necessarily at later stages. A pulse technique has been developed that is able to measure the forward magnetization transfer rates between bound and free protons (Kf) with good precision. The preliminary results demonstrated a sizable decrease in Kf during and after the period of ischemia; Kf contrast appeared to be irreversible upon reperfusion and correlated with known regions of cell damage. It is proposed to measure the temporal and spatial profile of Kf in rats subjected to permanent MCAO to provide a test of the hypothesis that a decrease in Kf will be associated with cell damage as seen by histopathology. The association between the post-ictal increase in T2 and decrease in Kf will also be investigated in the same rat model to test the hypothesis that the co-distribution of T2 and Kf can be segmented to provide information about ischemic cell damage, and in particular, that an increase of tissue water will cause an increase of T2 and a simultaneous decrease of Kf.