Improved non-invasive MR brain thermometry for therapeutic hypothermia

项目摘要 脑温度对创伤后神经保护和恢复的重要性不可低估。 心脏骤停和中风后的患者预后与体温密切相关，体温适中 体温和脑温的升高与脑损伤的严重程度和死亡率呈正相关。 相反，诱导低温或降温被认为是减轻进一步损伤的一种治疗措施。 大脑和最大限度地保存组织，以便在心脏骤停、中风和脑创伤后恢复。治疗性的 降温是通过核心体温监测和生物反馈实现的，但它很好地- 确定这些测量是不准确和不一致的大脑温度的代替品。植入 体温探测器表明，大脑温度高于体温，而这些 在受伤之后，分歧被进一步夸大了。由于冷却没有在剂量或 患者的选择和治疗后的患者结果是可变的，脑温测量可能是 改善和优化这一有希望的干预措施的一个关键但尚未探索的方面。临床脑 体温测量仅限于通过外科手术植入单一位置的侵入性温度探头， 在大多数患者群体中是不切实际的。虽然几种基于磁共振(MR)的测温方法 已经提出并在研究环境中进行了演示，但大多数仍限于对 并且非常容易受到与组织异质性相关的误差的影响。这款R21的总体目标是 开拓者的提议是开发一种用于磁共振化学位移测温的新方法，同时， 描述患者在低温治疗过程中的脑-体温差。我们将开发一种 磁共振测温的组织特异性方法，校正与温度无关的化学位移， 在绝对测量中引入误差(目标1)。因为大脑-身体温度脱钩可能是一种 伤害和治疗监测的重要标志，心脏骤停将实施脑温测定 接受治疗性低温治疗的患者无创测量脑-体温差 (目标2)。我们预计，这些研究将扩大我们对大脑体温调节和 治疗性低温期间的神经保护，并提供了走向个性化的关键第一步 温度管理的方法。

Project Summary The importance of brain temperature for neuroprotection and recovery after trauma cannot be understated. Patient outcomes after cardiac arrest and stroke are strongly associated with temperature, where modest increases in body and brain temperatures correlate positively with severity of brain injury and mortality. Conversely, induced hypothermia or cooling is recognized as a therapeutic measure to mitigate further injury of the brain and maximally preserve tissue for recovery after cardiac arrest, stroke, and brain trauma. Therapeutic hypothermia is implemented using core body temperature monitoring and biofeedback, but it is well- established that these measurements are inaccurate and inconsistent proxies of brain temperature. Implanted temperature probes have demonstrated that brain temperature is higher than body temperature and these differences are further exaggerated after injury. As cooling has not been optimized in terms of dosage or patient selection, and patient outcomes after treatment are variable, brain temperature measurements may be a critical yet unexplored aspect of improving and optimizing this promising intervention. Clinical brain thermometry is limited to invasive temperature probes surgically implanted at a single location and is impractical in most patient cohorts. While several magnetic resonance (MR)-based thermometry methods have been proposed and demonstrated in research environments, most are still limited to relative estimations of temperature and are highly vulnerable to tissue heterogeneity-related errors. The overall goal of this R21 Trailblazer proposal is to develop a new approach for MR chemical shift thermometry and, in parallel, characterize brain-body temperature differences in patients during hypothermia treatment. We will develop a tissue-specific approach for MR thermometry, correcting for temperature-independent chemical shifts that introduce errors in absolute measurements (Aim 1). As brain-body temperature decoupling may be an important marker for injury and treatment monitoring, brain thermometry will be implemented in cardiac arrest patients undergoing therapeutic hypothermia to non-invasively measure brain-body temperature differences (Aim 2). We anticipate that these studies will expand our understanding of brain thermoregulation and neuroprotection during therapeutic hypothermia and provide a crucial first step towards a personalized approach to temperature management.