Wijeakumar Sobanawartiny, Spencer John P, Bohache Kevin, Boas David A, Magnotta Vincent A
Neuroimage. 2015 Feb 1;106:86-100. doi: 10.1016/j.neuroimage.2014.11.022.
Functional near-infrared spectroscopy (fNIRS) is an imaging technique that relies on the principle of shining near-infrared light through tissue to detect changes in hemodynamic activation. An important methodological issue encountered is the creation of optimized probe geometry for fNIRS recordings. Here, across three experiments, we describe and validate a processing pipeline designed to create an optimized, yet scalable probe geometry based on selected regions of interest (ROIs) from the functional magnetic resonance imaging (fMRI) literature. In experiment 1, we created a probe geometry optimized to record changes in activation from target ROIs important for visual working memory. Positions of the sources and detectors of the probe geometry on an adult head were digitized using a motion sensor and projected onto a generic adult atlas and a segmented head obtained from the subject's MRI scan. In experiment 2, the same probe geometry was scaled down to fit a child's head and later digitized and projected onto the generic adult atlas and a segmented volume obtained from the child's MRI scan. Using visualization tools and by quantifying the amount of intersection between target ROIs and channels, we show that out of 21 ROIs, 17 and 19 ROIs intersected with fNIRS channels from the adult and child probe geometries, respectively. Further, both the adult atlas and adult subject-specific MRI approaches yielded similar results and can be used interchangeably. However, results suggest that segmented heads obtained from MRI scans be used for registering children's data. Finally, in experiment 3, we further validated our processing pipeline by creating a different probe geometry designed to record from target ROIs involved in language and motor processing.
功能近红外光谱技术（fNIRS）是一种成像技术，它基于近红外光穿透组织的原理来检测血液动力学激活的变化。遇到的一个重要方法学问题是为fNIRS记录创建优化的探头几何形状。在此，通过三个实验，我们描述并验证了一个处理流程，该流程旨在根据功能磁共振成像（fMRI）文献中选定的感兴趣区域（ROI）创建优化且可扩展的探头几何形状。在实验1中，我们创建了一种探头几何形状，其经过优化以记录对视觉工作记忆重要的目标ROI的激活变化。使用运动传感器对探头几何形状的光源和探测器在成人头部上的位置进行数字化处理，并投影到通用成人图谱和从受试者的MRI扫描获得的分割头部上。在实验2中，将相同的探头几何形状缩小以适合儿童头部，随后进行数字化处理并投影到通用成人图谱和从儿童的MRI扫描获得的分割体积上。使用可视化工具并通过量化目标ROI与通道之间的相交量，我们表明在21个ROI中，分别有17个和19个ROI与成人和儿童探头几何形状的fNIRS通道相交。此外，成人图谱和成人受试者特定的MRI方法都产生了相似的结果，并且可以互换使用。然而，结果表明应使用从MRI扫描获得的分割头部来注册儿童数据。最后，在实验3中，我们通过创建一种不同的探头几何形状进一步验证了我们的数据处理流程，该探头几何形状旨在记录参与语言和运动处理的目标ROI的数据变化。
