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

我们已经开发了多核和多模态磁共振显微成像（MRI）技术，用于分析大脑功能和各种大脑疾病，无论是实验还是临床。这些方法是;（1）用于检测脑中各种代谢物的快速化学位移成像（CSI）方法，（2）使用超快MRI的扩散加权成像（EPI-DWI），（3）使用动脉自旋标记法的灌注成像（Perfusion Imaging）和（4）使用超快MRI的功能MRI。~ 1 P-MRS可检测能量代谢和磷脂代谢<31>，脑肿瘤和婴儿脑组织中磷酸单酯的增加反映了磷脂代谢的改变。脑梗塞时磷酸肌酸减少、乳酸增加提示有氧代谢障碍。氨基酸、胆碱、肌酸和乳酸可以通过 ...更多信息 脑肿瘤、退行性疾病和脑梗塞中N-乙酰天冬氨酸（NAA）的减少表明神经元的丢失。在恶性肿瘤和梗死的缺氧细胞组分中观察到乳酸增加。在EPI-DWI中，在超急性期（例如发病后30分钟）检测到脑梗死。EPI-DWI可作为诊断脑血管疾病的首选方法。采用动脉自旋标记法（FAIR）的灌注成像可用于检测脑血流的相关变化，但对于1.5T系统的临床应用仍有较高的灵敏度要求。目前，利用MRI了解脑血流动力学的灌注成像是可行的，EPI-DWI与灌注成像的结合有可能提示脑组织损伤的可逆性。在功能磁共振成像（fMRI）中，观察到的信号强度增加，在初级皮质区对应于每个激活任务，如手指运动，光刺激和听觉的话。功能磁共振成像也通过想象等复杂任务获得。快速fMRI可以检测初级和次级运动皮层激活的时间差异。虽然目前功能磁共振成像技术还存在一些问题，但它具有很高的时间和空间分辨率，是一种无创的脑功能评价方法。多模态MR方法是无创检查脑代谢和功能以及检查各种脑疾病的病理生理学的独特而有用的方法。从这个意义上说，应继续进行进一步的研究。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