Wang Bingyuan, Pan Tiantian, Zhang Yao, Liu Dongyuan, Jiang Jingying, Zhao Huijuan, Gao Feng
Opt Express. 2019 Feb 4;27(3):3229-3246. doi: 10.1364/OE.27.003229.
In functional near-infrared spectroscopy (fNIRS), the conventional indirect approaches first separately recover the spatial distribution of the changes in the optical properties at every time point, and then extract the activation levels by a time-course analysis process at every site. In the tomographic implementation of fNIRS, i.e., diffuse optical tomography (DOT), these approaches not only suffer from the ill-posedness of the optical inversions and error propagation between the two successive steps, but also fail to achieve satisfactory temporal resolution due to the requirement for a complete data set. To cope with the above adversities of the indirect approaches, we propose herein a direct approach to tomographically reconstructing the activation levels by incorporating a Kalman scheme. Dynamic simulative and phantom experiments were conducted for the performance validation of the proposed approach, demonstrating its potentials to improve the calculated images and to relax the speed limitation of the instruments.
在功能近红外光谱技术（fNIRS）中，传统的间接方法首先在每个时间点分别恢复光学特性变化的空间分布，然后通过在每个位点的时程分析过程提取激活水平。在fNIRS的断层成像实现中，即扩散光学断层成像（DOT），这些方法不仅受到光学反演的不适定性以及两个连续步骤之间的误差传播的影响，而且由于对完整数据集的要求而无法实现令人满意的时间分辨率。为了应对间接方法的上述不利因素，我们在此提出一种通过结合卡尔曼方案断层重建激活水平的直接方法。针对所提出方法的性能验证进行了动态模拟和体模实验，证明了其在改善计算图像和放宽仪器速度限制方面的潜力。
