Brigadoi Sabrina, Phan Phong, Highton David, Powell Samuel, Cooper Robert J, Hebden Jeremy, Smith Martin, Tachtsidis Ilias, Elwell Clare E, Gibson Adam P
University College London, Department of Medical Physics and Biomedical Engineering, Biomedical Optics Research Laboratory, London, United Kingdom.
University of Padova, Department of Developmental and Social Psychology, Padova, Italy.
Neurophotonics. 2017 Apr;4(2):021105. doi: 10.1117/1.NPh.4.2.021105. Epub 2017 May 24.
In diffuse optical tomography (DOT), overlapping and multidistance measurements are required to reconstruct depth-resolved images of oxy- ([Formula: see text]) and deoxy- (HHb) hemoglobin concentration changes occurring in the brain. These can be considered an indirect measure of brain activity, under the assumption of intact neurovascular coupling. Broadband systems also allow changes in the redox state of cytochrome c oxidase (oxCCO) to be measured, which can be an important biomarker when neurovascular coupling is impaired. We used DOT to reconstruct images of [Formula: see text], [Formula: see text], and [Formula: see text] from data acquired with a broadband system. Four healthy volunteers were measured while performing a visual stimulation task (4-Hz inverting checkerboard). The broadband system was configured to allow multidistance and overlapping measurements of the participants' visual cortex with 32 channels. A multispectral approach was employed to reconstruct changes in concentration of the three chromophores during the visual stimulation. A clear and focused activation was reconstructed in the left occipital cortex of all participants. The difference between the residuals of the three-chromophore model and of the two-chromophore model (recovering only [Formula: see text] and [Formula: see text]) exhibits a spectrum similar to that of oxCCO. These results form a basis for further studies aimed to further optimize image reconstruction of [Formula: see text].
在扩散光学断层扫描（DOT）中，需要进行重叠和多距离测量，以重建大脑中氧合血红蛋白（[公式：见正文]）和脱氧血红蛋白（HHb）浓度变化的深度分辨图像。在完整的神经血管耦合假设下，这些可被视为大脑活动的间接测量指标。宽带系统还允许测量细胞色素c氧化酶（oxCCO）的氧化还原状态变化，当神经血管耦合受损时，这可能是一个重要的生物标志物。我们使用DOT从宽带系统获取的数据中重建[公式：见正文]、[公式：见正文]和[公式：见正文]的图像。在四名健康志愿者执行视觉刺激任务（4赫兹反转棋盘格）时进行了测量。宽带系统配置为通过32个通道对参与者的视觉皮层进行多距离和重叠测量。采用多光谱方法重建视觉刺激期间三种发色团浓度的变化。在所有参与者的左枕叶皮层中重建出清晰且集中的激活。三发色团模型和双发色团模型（仅恢复[公式：见正文]和[公式：见正文]）的残差之间的差异呈现出与oxCCO相似的光谱。这些结果为旨在进一步优化[公式：见正文]图像重建的进一步研究奠定了基础。
