Improved Measurement of Celebral Perfusion with MRI

该项目广泛的长期目标是改善缺血性脑卒中的诊断和治疗。 中风患者 缺血性中风是工业化世界中第三大致死和致残原因。在美国 仅每年就有50万至75万人患中风。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药物治疗 溶解血凝块的疗法（血栓溶解）。溶栓已被证明可以降低死亡率， 与中风相关的残疾，但具有严重的破坏性脑出血（ICH）风险， 表明需要仔细分类如果没有一种预测ICH的方法， 90%的中风患者有证据表明，了解CBF（ml/100g-min）有助于预测ICH， 急性中风患者。缺血性中风治疗的一个主要障碍是缺乏广泛的 用于分流的定量CBF的可用方法!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， 我们将在缺血性斯托克动物模型和脑卒中模型中验证这种诊断技术。 急性和慢性缺血患者。我们将证明qCBF可用于对患者进行风险分层， 通常不适合溶栓的患者可以安全地接受这种挽救生命的治疗， 疗法本提案的具体目的是检验以下假设： 特定目的1：MRI灌注测量可以准确定量正常犬的CBF。 特定目标2：MRI灌注测量可以准确定量缺血性犬模型的CBF 中风 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值可预测颅内出血 由血栓溶解引起的。 成功完成这项工作后，我们将开发并验证一种新的MRI方法 量化脑血流量来对急性中风患者进行分类。

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/1 OOg-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 CBFfor 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 MRImethod that quantifies CBFfor the triage of acute stroke patients.