VALIDATION OF MAGNETIC RESONANCE PERFUSION IMAGING

描述(改编自申请者摘要)：目标是优化和 磁共振成像(MRI)团注通道灌注技术的验证 在中风患者身上。最近发现的灌注/扩散磁共振成像技术是 在本十年中，急性卒中护理领域最有希望的发展之一 因为它们可以潜在地区分缺血核心和周围 低灌流但可挽救的组织。目前，最弱的组成部分是 急性卒中的MRI研究是一种灌注性研究。目前还没有直接的 核磁共振灌注成像能准确检测半影区低血流灌注 与中风患者的“金标准”方法进行比较。没有一支球队 定义了最佳灌注扫描参数的配方，然后验证 这份食谱是针对中风患者的金本位的。目前还没有直接的 对通常提出的对数线性关系假设的验证 血管内造影剂浓度及MRI信号改变。同样，不 经过验证的数据分析配方已经问世。氧-15水正电子发射 体层摄影术(PET)血流评估将作为金标准 验证中风患者的磁共振灌注成像研究。磁共振成像和正电子发射计算机断层成像评价 血液流动将是背靠背的。医学上稳定的中风患者 将研究亚急性时期(&lt；48小时)。这些患者预计会 显示范围广泛的血液流量值，将提供高动态 测试核磁共振灌注成像准确性的范围，但又足够稳定 这两项研究都进行了。不同MRI扫描方式下的MRI灌注扫描 参数和分析方法将对照PET金进行评估 标准的。利用经过验证的核磁共振成像程序，计划进行进一步的试点研究 目的：探讨磁共振成像能否准确识别脑血流灌注异常。 有血管疾病的渐近受试者的脑血管储备不足 中风的危险因素。加州大学洛杉矶分校拥有最先进的核磁共振和正电子发射计算机断层扫描技术 设备和具有中风专业知识的积极协作团队 在MRI扫描和PET中的临床管理(包括急性和康复) 扫描中。

DESCRIPTION (Adapted from Applicant's Abstract): The aim is to optimize and validate the Magnetic Resonance Imaging (MRI) bolus passage perfusion technique in stroke victims. Recently discovered perfusion/diffusion MRI techniques are among the most promising developments in acute stroke care in this decade because they can potentially distinguish the ischemic core from surrounding hypoperfused but salvageable tissue. At present, the weakest component of the acute stroke MRI study is the perfusion study. There has been no direct demonstration that perfusion MRI accurately detects penumbral hypoperfusion by comparison with a "gold standard" method in stroke patients. No team has defined a recipe of optimal perfusion scanning parameters and then validated this recipe in stroke victims against a gold standard. There has been no direct validation of the usually-made assumption of a log-linear relationship between intravascular contrast agent concentration and MRI signal change. Likewise, no proven data analysis recipe has come forth. Oxygen-15 water Positron Emission Tomography (PET) blood flow assessment will be used as gold standard to validate perfusion MRI studies of stroke victims. MRI and PET assessment of blood flow will be made back-to-back. Medically stable stroke patients in the subacute epoch (< 48 hrs) will be studied. These patients are expected to display a wide range of blood flow values which will provide a high dynamic range over which to test the accuracy of perfusion MRI, yet be stable enough to undergo both studies. MRI perfusion scans using different MRI scanning parameters and analysis methods will be evaluated against the PET gold standard. Using the validated MRI procedures, a further pilot study is planned to explore whether MRI can accurately identify perfusion abnormalities and cerebrovascular reserve deficiencies in asymptotic subjects who have vascular risk factors for stroke. UCLA has new state-of-the-art MRI and PET imaging devices together with active collaborating teams having expertise in stroke clinical management (both acute and rehabilitative), in MRI scanning and in PET scanning.