An increased pulse pressure, due to arteries stiffening with age and cardiovascular disease, may lead to downstream brain damage in microvessels and cognitive decline. Brain-wide imaging of the pulsatility propagation from main feeding arteries to capillaries in small animals could improve our understanding of the link between pulsatility and cognitive decline. However, it requires higher spatiotemporal resolution and penetration depth than currently available with existing brain imaging techniques. Herein, we show the feasibility of performing Dynamic Ultrasound Localization Microscopy (DULM), a novel imaging approach to capture hemodynamics with a subwavelength resolution. By producing cine-loops of flowing microbubbles in 2D in the whole rodent brain lasting several cardiac cycles, DULM performed pulsatility measurements in microvessels in-depth, in vivo, with and without craniotomy. Cortical veins and arteries were shown to have a significatively different pulsatility index and the method was compared against Contrast Enhanced Ultrafast Ultrasound Doppler (CEUFD) pulsatility measurements.

中文翻译：

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使用动态超声定位显微镜测量啮齿类动物脑微循环的体内搏动


由于动脉随着年龄的增长和心血管疾病而硬化，脉压增加可能会导致下游脑部微血管损伤和认知能力下降。对小动物从主供血动脉到毛细血管的搏动传播进行全脑成像可以提高我们对搏动与认知能力下降之间联系的理解。然而，它需要比目前现有脑成像技术更高的时空分辨率和穿透深度。在此，我们展示了执行动态超声定位显微镜（DULM）的可行性，这是一种以亚波长分辨率捕获血流动力学的新颖成像方法。通过在整个啮齿类动物大脑中产生持续几个心动周期的二维流动微泡电影循环，DULM 在体内（无论是否进行开颅手术）对微血管进行深入的脉动测量。皮层静脉和动脉具有显着不同的搏动指数，并将该方法与对比增强超快超声多普勒 (CEUFD) 搏动测量进行比较。