VALIDATION OF MRI PERFUSION TECHNIQUES

描述（改编自申请人的摘要）：磁共振成像 (MRI)技术，正在迅速发展，以允许定量 评估实验动物和 伙计 这些基于MRI的方法提供了许多优于其他技术的优点 例如惰性Xe 131-CT或H2O 15 PET，因为它们是非侵入性的， 采集的数据与高分辨率解剖、功能和 大脑代谢的光谱图像。 这些基于MRI的新方法 灌注评估基于动脉自旋标记技术 首先介绍了由威廉姆斯等。包括EPISTAR、FAIR、UNFAIR和 俏皮话。 这些技术刚刚开始应用于临床 环境，虽然它们非常有前途，但需要验证 这些方法，并检查其使用中的错误来源。 的 申请人建议系统地调查 这些技术包括估计渡越时间和划分 系数、动脉弛豫时间和磁化传递效应。 他们还将比较获得的脑灌注估计值与 这些基于MR的技术与成熟的CBF技术 使用标记的微球的心内推注进行测量。 这些研究将在非病理性正常灌注脑中进行， 以及在缺血条件下使用大脑中动脉闭塞， 大鼠 这项工作可以提高基于MRI的测量的可靠性， 脑灌注，因此，将提供他们的日常生活 应用于临床和研究环境。

DESCRIPTION (Adapted from Applicant's Abstract): Magnetic Resonance Imaging (MRI) techniques, are rapidly being developed to allow for the quantitative assessment of cerebral blood flow (CBF) in both experimental animals and man. These MRI-based methods offer many advantages over other techniques like inert Xe131-CT, or H2O15 PET, because they are non-invasive and can be acquired registered to high resolution anatomical, functional, and spectroscopic images of cerebral metabolism. These new MRI-based methods of perfusion assessment are based upon the arterial spin labeling technique first introduced by Williams et. al. and include EPISTAR, FAIR, UNFAIR and QUIPPS. These techniques are just beginning to be applied in the clinical setting, and although they are very promising, there is a need to validate these methods and to examine the sources of error in their use. The applicants proposed to systematically investigate the sources of error of these techniques including estimates of transit times and partition coefficients, arterial relaxation times and magnetization transfer effects. They would also compare the estimates of cerebral perfusion obtained with these MR-based techniques with the well established technique of CBF measurement using intracardiac bolus injection of labeled microspheres. These studies would be conducted in nonpathologic normally perfused brain, and under ischemic conditions using middle cerebral artery occlusion in rats. This work could improve the reliability of MRI based measurements of cerebral perfusion and would, therefore, provide for their routine application in clinical and research settings.