Significance: Quantitative measures of blood flow and metabolism are essential for improved assessment of brain health and response to ischemic injury. Aim: We demonstrate a multimodal technique for measuring the cerebral metabolic rate of oxygen (CMRO2) in the rodent brain on an absolute scale (μM O2 / min). Approach: We use laser speckle imaging at 809 nm and spatial frequency domain imaging at 655, 730, and 850 nm to obtain spatiotemporal maps of cerebral blood flow, tissue absorption (μa), and tissue scattering (μs ′ ). Knowledge of these three values enables calculation of a characteristic blood flow speed, which in turn is input to a mathematical model with a “zero-flow” boundary condition to calculate absolute CMRO2. We apply this method to a rat model of cardiac arrest (CA) and cardiopulmonary resuscitation. With this model, the zero-flow condition occurs during entry into CA. Results: The CMRO2 values calculated with our method are in good agreement with those measured with magnetic resonance and positron emission tomography by other groups. Conclusions: Our technique provides a quantitative metric of absolute cerebral metabolism that can potentially be used for comparison between animals and longitudinal monitoring of a single animal over multiple days. Though this report focuses on metabolism in a model of ischemia and reperfusion, this technique can potentially be applied to far broader types of acute brain injury and whole-body pathological occurrences.

中文翻译：

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高速定量光学成像在大鼠皮层中的绝对代谢

意义：血流和代谢的定量测量对于改善对大脑健康的评估和对缺血性损伤的反应至关重要。目的：我们展示了一种多峰技术，用于以绝对规模（μMO2 /分钟）测量啮齿动物大脑中氧的大脑新陈代谢速率（CMRO2）。方法：我们使用809 nm的激光散斑成像和655、730和850 nm的空间频域成像来获得脑血流，组织吸收（μa）和组织散射（μs）的时空图。了解这三个值可以计算出特征血流速度，然后将其输入到具有“零流量”边界条件的数学模型中，以计算绝对CMRO2。我们将此方法应用于心脏骤停（CA）和心肺复苏的大鼠模型。有了这个模型，零流量条件发生在进入CA的过程中。结果：用我们的方法计算出的CMRO2值与其他组通过磁共振和正电子发射断层扫描所测得的值非常吻合。结论：我们的技术提供了绝对的大脑代谢的定量指标，可潜在地用于动物之间的比较以及多日内对单个动物的纵向监测。尽管此报告的重点是缺血和再灌注模型中的代谢，但该技术可潜在地应用于更广泛类型的急性脑损伤和全身病理事件。结论：我们的技术提供了绝对的大脑代谢的定量指标，可潜在地用于动物之间的比较以及多日内对单个动物的纵向监测。尽管此报告的重点是缺血和再灌注模型中的代谢，但该技术可潜在地应用于更广泛类型的急性脑损伤和全身病理事件。结论：我们的技术提供了绝对的大脑代谢的定量指标，可潜在地用于动物之间的比较以及多日内对单个动物的纵向监测。尽管此报告的重点是缺血和再灌注模型中的代谢，但该技术可潜在地应用于更广泛类型的急性脑损伤和全身病理事件。