Specialized Program of Translational Research in Acute Stroke at the Partners Hea

这项工作的长期目标是开发和验证一种新的，临床上有用的，位置加权CT 基于灌注（CTP）的工具，用于预测因挽救缺血组织而导致的最大临床恢复 再灌注。第一步是确定如何最好地预测组织的命运， 存在早期再灌注。虽然这本身就是一个重大的进步，但急性中风治疗的目标 是最大限度地减少神经缺陷和最大限度地提高功能效果。仅预测潜在的组织挽救 不足以评估干预的风险与受益，极端情况除外，即，大量 组织处于危险中，或者没有可挽救的组织。一种预测预期临床改善的方法， 组织挽救的范围和位置是急性中风成像的最终目标。 由于CT的上级定量能力，与MR、灌注成像相反， 特异性CT脑血流量（CT-CBF）和血容量（CT-CBV）阈值，以预测组织存活，或 梗塞似乎有希望。因为小规模的研究表明， 由于再灌注与NIHSS改善相关，因此必须验证这些阈值， 已知再灌注状态的较大患者队列。因此，在目标1和2中，我们将建立CTP “核心”（尽管再灌注，组织可能死亡）和“良性低血症”（组织可能存活）的阈值 尽管持续灌注不足）。CTP值在这些极端值之间的缺血组织反映了 “不稳定半暗带”（具有可变结果的组织，取决于不稳定半暗带的程度、范围和时间）。 再灌注）。在目标2.iii中，我们将确认CT血管造影源图像（CTA-SI），其中涵盖 整个大脑，不需要后处理，并且在扫描完成时立即可用，也可以使用 以灵敏地确定梗塞“核心”。在目标3中，我们将开始开发临床预测模型， 估计“与再灌注相关的NIHSS评分的最大预期临床改善”。

The long-range goal of this work is to develop and validate a novel, clinically useful, location-weighted CT perfusion (CTP) based tool to predict the maximal clinical recovery attributable to salvage of ischemic tissue with reperfusion. The first step is to ascertain how best to predict tissue fate depending on whether or not there is early reperfusion. Although this in itself would be a major advance, the goal of acute stroke treatment is to minimize neurological deficit and maximize functional outcome. Predicting only potential tissue salvage is inadequate to assess the risk versus benefit of intervention, except for extreme cases, i.e., large volume of tissue at risk, or no salvageable tissue. A method that predicts expected clinical improvement based on extent and location of tissue salvage is the ultimate goal of acute stroke imaging. Owing to the superior quantitative capability of CT, as opposed to MR, perfusion imaging, the application of specific CT cerebral blood flow (CT-CBF) and blood volume (CT-CBV) thresholds to predict tissue survival or infarction appears promising. Because smaller studies have suggested that the calculated volume salvaged by reperfusion is correlated with improvement in NIHSS, it is essential that these thresholds be validated in larger patient cohorts for which reperfusion status is known. In Aims 1 and 2, we will therefore establish CTP thresholds for "core" (tissue likely to die despite reperfusion) and "benign oligemia" (tissue likely to survive despite persistent hypoperfusion). Ischemic tissue with CTP values between these extremes reflects "unstable penumbra" (tissue with variable outcome, depending on the degree, extent, and timing of reperfusion). In Aim 2.iii, we will confirm that CT angiographic source images (CTA-SI), which cover the entire brain, require no post processing, and are available immediately at scan completion, can also be used to sensitively determine infarct "core". In Aim 3, we will begin to develop a clinical prediction model to estimate "maximal expected clinical improvement in NIHSS scoring associated with reperfusion".