Imaging the Ischaemic Penumbra using BOLD MRI with oxygen challenge as a metabolic biotracer

中风是主要的杀手，与其他任何慢性病相比，中风对残疾的影响更大。患者占据了所有患者组中最多的急性住院天数(每年260万天)，这种疾病消耗了NHS支出的4%-6%(约28亿GB)，预计到2010年，随着预期寿命和存活率的增加，成本将上升30%。治疗选择有限(如rt-PA或阿司匹林等破血栓药物)，只有不到2%的中风患者接受rt-PA治疗，因为出于安全原因，必须在中风后3小时内给予rt-PA，而且患者必须首先进行脑部扫描，以排除脑出血。Rt-PA在脑损伤尚未完全演变的患者中非常有效。在中风后的头几个小时，受伤但有可能挽救的组织(半影区)可以通过rt-PA挽救。核磁共振成像(MRI)可以识别半影区组织，但目前的技术低估了半影区的大小。如果有一种快速、更准确的核磁共振技术，更多的患者可以得到治疗，并招募到临床试验中来研究新的疗法，这一点会得到改善。这项建议描述了这种技术的开发和验证，并提供了来自动物模型和人类的初步MRI数据。

Stroke is a major killer, and has a greater disability impact than any other chronic disease. Patients occupy one of the largest numbers of acute hospital bed days of any patient group (2.6 million per year), and the disease consumes between 4-6% of NHS expenditure (approx £2.8 billion) with costs projected to rise 30% by 2010 as life expectancy and survive rates increase. Treatment options are limited (clot busting drugs like rt-PA or aspirin) with less than 2% of stroke patients receiving rt-PA since it must be given within 3 hours of stroke for safety reasons, and patients must have a brain scan first to rule out brain haemorrhage. rt-PA is very effective in patients where brain damage has not fully evolved. In the first few hours after stroke, injured but potentially salvageable tissue (penumbra) can be saved by rt-PA. Penumbral tissue can be identified by magnetic resonance imaging (MRI), but current techniques underestimate penumbra size. If a rapid, more accurate MRI technique was available, more patients could be treated and recruitment into clinical trials to study new therapies, improved. This proposal describes development and validation of such a technique and provides preliminary MRI data from animal models and man.