Improved Measurement of Celebral Perfusion with MRI

描述（由申请人提供）：该项目的广泛、长期目标是改善缺血性卒中患者的诊断和治疗。缺血性中风是工业化世界中第三大致死和致残原因。仅在美国，每年就有50万至75万人受到中风的影响。在缺血性中风中，血凝块阻塞了供给大脑的血管。急性缺血性中风可以通过使用溶解血栓的药物治疗（溶栓）来治疗。溶栓已被证明可以减少与卒中相关的死亡和残疾，但具有严重的破坏性脑出血（ICH）风险，这表明需要仔细分类。由于没有预测ICH的方法，超过90%的卒中患者必须拒绝溶栓治疗。有证据表明，了解CBF（ml/100 g-min）有助于预测急性脑卒中患者的ICH。缺血性卒中治疗的一个主要障碍是缺乏一种广泛可用的方法来量化CBF以进行分类。这促使美国心脏和中风协会建议：“必须进行更多的研究，使这些技术，特别是基于MR的方法，可量化”。我们最近开发了一种新的MRI脉冲序列定量CBF。我们将在缺血性斯托克动物模型和急性和慢性缺血患者中验证这种诊断技术。我们将证明qCBF可用于对患者进行风险分层，以便通常不符合溶栓条件的患者可以安全地接受这种挽救生命的治疗。本提案的具体目的是测试以下假设：具体目标1：MRI灌注测量可以准确地量化正常犬的CBF。具体目标2：MRI灌注测量可以准确地定量脑血流缺血性中风犬模型。具体目标3：MRI测量可以预测慢性缺血患者的CBF。具体目标4：在急性卒中患者中，定量CBF值可以预测溶栓导致的颅内出血。成功完成这项工作后，我们将开发并验证一种新的MRI方法，该方法可以量化脑血流，用于急性卒中患者的分诊。

DESCRIPTION (provided by applicant): The broad, long-term objective of this project is to improve the diagnosis and treatment of ischemic stroke patients. Ischemic stroke is the third leading cause of death and disability in the industrialized world. In the US alone, between 500,000 and 750,000 people are affected by stroke each year. In an ischemic stroke, a blood clot blocks a blood vessel feeding the brain. Acute ischemic stroke is treatable through the use of drug therapies that dissolve blood clots (thrombolysis). Thrombolysis has been shown to reduce the death and disability associated with stroke, but carries significant risk of devastating intracerebral hemorrhage (ICH), indicating the need for careful triage. Without a means to predict ICH, thrombolysis must be denied to over 90% of stroke patients. Evidence has shown that knowledge of CBF in ml/100g-min can help predict ICH in acute stroke patients. A major impediment in treatment of ischemic stroke is the lack of a widely available method for quantifying CBF for triage. This has prompted the American Heart and Stroke Association to recommend: "More research must be conducted to make these techniques, especially the MR-based methods, quantifiable". We have recently developed a novel MRI pulse sequence for quantitative CBF. We will validate this diagnostic technique in both animal models of ischemic stoke and in a patients with acute and chronic ischemia. We will show that qCBF can be used to risk stratify patients so that patients who would not normally be eligible for thrombolysis can be safely treated with this lifesaving therapy. The specific aims of this proposal are to test the following hypotheses: Specific Aim 1: MRI measurements of perfusion can accurately quantify CBF in normal canines. Specific Aim 2: MRI measurements of perfusion can accurately quantify CBF a canine model of ischemic stroke. Specific Aim 3: MRI measurements can predict CBF in chronic ischemic patients. Specific Aim 4: In acute stroke patients, quantitative CBF values can predict intracranial hemorrhage resulting from thrombolysis. Upon successful completion of this work we will have developed and validated a new MRI method that quantifies CBF for the triage of acute stroke patients.