脑缺血区水分子扩散变化及其异常溶积双峰的机制研究

To study the pathophysiological mechanism of water molecular diffusion changes by detecting the microcirculation and the intracellular Ca2+ level. The result demonstrated that the PWI decline area was larger than DWI. The overloading of Ca2+ occurred as the CBF decreased 25% and the ADC changes in the penumbra region correlated obviously with the level of Ca2+. The results explained why MK-801 could reduce the diffusion changes. Simultaneously, the results provided a new methods to monitor and inspect the effects of neuroprotective drug for cerebral ischemia in vivo. The obvious correlation between ADC and intracellular Ca2+ indicated that ADC changes may occur in various neuron damages, so diffusion changes occurred in ischemic damage area may not be specific: the specificity of DWI in the diagnosis of cerebral ischemia may have been overestimated. For the results and speculations above, a clinical trials were performed prospectively,and the false positive cases were demonstrated in the diagnosis of cerebral ischemia by using DWI. The diffusion tensor characteristics of corresponding cerebral lesions was also studied. On the one hand, the diagnosic value of DWI has been evaluated objectively,and the wrong impression in the diagnosis value of DWI was corrected. On the other hand, a new study field of brain diseases by using DWI has been explored, especially in brain white matter diseases.

本课题应用功能性磁共振成像于活体研究脑缺血区水分子扩散运动.异常及其异常容积双峰的生物物理学机制，包括其变化与演变的血液动力学基础，脑缺血后神经元操作的细胞内钠、钾、钙及酸中毒等的离子紊乱基础。明确脑缺血功能性磁共振表现的生物物理学机制，明确脑缺血损伤的生物物理学机制以及扩散成像在脑缺血早期诊治中的价值。..