Giannoni Luca, Lange Frédéric, Sajic Marija, Smith Kenneth J, Tachtsidis Ilias
Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK.
Department of Neuroinflammation, UCL Queen Square Institute of Neurology, London, WC1N 3BG2, UK.
IEEE J Sel Top Quantum Electron. 2021 Jan 22;27(4). doi: 10.1109/JSTQE.2021.3053634. eCollection 2021 Jul-Aug.
We present a novel hyperspectral imaging (HSI) system using visible and near-infrared (NIR) light on the exposed cerebral cortex of animals, to monitor and quantify changes in the oxygenation of haemoglobin and in cellular metabolism via measurement of the redox states of cytochrome-c-oxidase (CCO). The system, named hNIR, is based on spectral scanning illumination at 11 bands (600, 630, 665, 784, 800, 818, 835, 851, 868, 881 and 894 nm), using a supercontinuum laser coupled with a rotating Pellin-Broca prism. Image reconstruction is performed with the aid of a Monte Carlo framework for photon pathlength estimation and post-processing correction of partial volume effects. The system is validated on liquid optical phantoms mimicking brain tissue haemodynamics and metabolism, and finally applied on the exposed cortex of mice undergoing alternating oxygenation challenges. The results of the study demonstrate the capacity of hNIR to map and quantify the haemodynamic and metabolic states of the exposed cortex at microvascular levels. This represents (to the best of our knowledge) the first example of simultaneous mapping and quantification of cerebral haemoglobin and CCO using visible and NIR HSI, which can potentially become a powerful tool for better understanding brain physiology.
我们展示了一种新型的高光谱成像（HSI）系统，该系统利用可见光和近红外（NIR）光照射动物暴露的大脑皮层，通过测量细胞色素c氧化酶（CCO）的氧化还原状态来监测和量化血红蛋白氧合及细胞代谢的变化。该系统名为hNIR，基于11个波段（600、630、665、784、800、818、835、851、868、881和894纳米）的光谱扫描照明，使用超连续谱激光器与旋转的佩林-布罗卡棱镜相结合。借助蒙特卡罗框架进行光子程长估计以及对部分容积效应进行后处理校正来进行图像重建。该系统在模拟脑组织血流动力学和代谢的液体光学模型上得到验证，最终应用于经历交替氧合挑战的小鼠暴露皮层。研究结果证明了hNIR在微血管水平绘制和量化暴露皮层血流动力学和代谢状态的能力。据我们所知，这是首个使用可见光和近红外高光谱成像同时绘制和量化脑血红蛋白及CCO的实例，它有可能成为更好理解脑生理学的强大工具。
