Application of cerebral blood flow and metabolism imaging with multi-nuclear, multi-modality MRI techniques to cerebral

我们开发了多核和多模式磁共振显微成像(MRI)技术，用于分析脑功能和各种脑部疾病，包括实验和临床。这些方法是：(1)快速化学位移成像(CSI)方法检测脑内各种代谢物；(2)超快磁共振弥散加权成像(EPI-DWI)；(3)动脉自旋标记灌注成像(EPI-DWI)；(4)超快磁共振成像(MRS)检测脑内各种代谢物，并用CSI方法显示其分布。能量代谢和磷脂代谢可用~(31)&gt；P-MRS进行检测。脑肿瘤和婴幼儿脑组织中磷单酯的增加提示磷脂代谢的改变。脑梗塞患者磷酸肌酸降低，乳酸升高，提示有氧代谢受损。可用…检测氨基酸、胆碱、肌酸和乳酸脑肿瘤、退行性疾病和脑梗塞中N-乙酰-天冬氨酸(NAA)的降低提示神经元的丢失。在恶性肿瘤和脑梗塞的低氧细胞组分中观察到乳酸的增加。在EPI-DWI中，脑梗塞在超急性阶段被发现，例如在发病30分钟后。EPI-DWI可作为脑血管疾病的首选检查方法。动脉自旋标记法(FAIR)脑血流灌注成像可用于检测脑血流的相对改变，但对于1.5T系统的临床应用仍需要更高的灵敏度。目前，使用对比剂的灌注成像对于了解磁共振脑血流动力学是实用的。EPI-DWI与灌注成像相结合有可能提示受损脑组织的可逆性。在功能磁共振成像(FMRI)中，在手指运动、光刺激和听单词等每项激活任务对应的初级皮质区，信号强度都有所增加。功能磁共振成像也是通过想象等复杂任务获得的。FAST fMRI可用于检测初级和次级运动皮质的激活时间差。虽然功能磁共振成像仍存在一些问题，但它具有较高的时间和空间分辨率，可用于无创性评估脑功能。多模式磁共振成像方法是一种独特的、有用的方法，可以无创地检测大脑的代谢和功能，并检查各种脑部疾病的病理生理机制。从这个意义上讲，还需要继续深入研究。较少

We have developed multi-nuclear and multi-modality magnetic resonance microscopic imaging (MRI) techniques for analysis of brain functions and various cerebral disorders, both experimentally and clinically. These methods are ; (1) Fast Chemical Shift Imaging (CSI) method for detecting various metabolite in the brain, (2) Diffusion-weighted imaging using ultrafast MRI (EPI-DWI), (3) Perfusion Imaging using arterial spin tagging method and (4) Functional MRI using ultrafast MRI.In magnetic resonance spectroscopy (MRS), various metabolites in the brain were detected and their distribution was visualized by the CSI method. Energy metabolism and phospholipid metabolism can be examined by ^<31>P-MRS.The increase of phosphomonoesters in brain tumors and infant brain indicates the changes of phospholipid metabolism. Decreased phosphocreatine and increased lactate in cerebral infarction indicate the impairment of aerobic metabolism. Amino acids, choline, creatine and lactate can be detected by … More ^1H-MRS.The decrease of N-acetyl aspartate (NAA) in brain tumors, degenerative diseases and cerebral infarction indicates the loss of neurons. Increased lactate was observed in hypoxic cell fractions in malignant tumors and infarction. In the EPI-DWI, cerebral infarction is detected at an ultra-acute stage such as 30 minutes after the onset. The EPI-DWI would be used as a first choice for detecting cerebral vascular diseases. The perfusion imaging using arterial spin tagging method (FAIR) is useful to detect the realative changes in cerebral blood flow, but it still requires more sensitivity for a clinical application using 1.5 T system. At moment, the perfusion imagin using contrast material is practical to know the cerebral hemodynamics using MRI.The combination of EPI-DWI and Perfusion Imaging can possibly indicate the reversibility of damaged brain tissue. In functional MRI (fMRI), an increase of signal intensity was observed in the primary cortical area corresponding to each activation task such as finger movements, photic stimulation and hearing words. The fMRI was also obtained by complex tasks such as imagination. Fast fMRI can be used to detect the time deference of activation in primary and secondary motor cortex. Although there are still some problems in fMRI, it is useful for evaluating brain function non-invasively with highly temporal and spatial resolution. The multi-modality MR methods are unique and useful methods to examine the brain metabolism and function non-invasively and to examine pathophysiology of various cerebral disorders. In this sense, further research should be continued. Less