Detection of an unstable and/or a weak probe contact in a multichannel functional near-infrared spectroscopy measurement
Detection of an unstable and/or a weak probe contact in a multichannel functional near-infrared spectroscopy measurement
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多通道功能近红外光谱测量中不稳定和/或弱探针接触的检测
DOI：
10.1117/1.jbo.18.4.047003
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发表时间：
2013
影响因子：
3.5
通讯作者：
梅山 伸二
中科院分区：
文献类型：
--
作者：
武田湖太郎;佐藤貴紀;南部功夫; 山田亨;梅山伸二;大高洋平;井上芳浩;大須理英子;和田安弘;加藤宏之;Shinji Umeyama and Toru Yamada;梅山 伸二
多通道功能近红外光谱测量涉及在受试者头部放置许多探头。探头和头部表面之间的稳定紧密接触至关重要。我们提出了一种方法来检测两种类型的有问题的探头接触的测量数据：一个不稳定的接触，其光传输很容易波动与身体运动，和一个弱的接触，其光传输是不断小。不稳定的接触导致大的基线波动，而弱接触导致大的噪声。由于由身体运动和噪声引起的吸光度变化显示出与组织血红蛋白吸收不同的光谱特性，因此它们具有与血红蛋白摩尔消光系数矢量所跨越的平面正交的分量。我们使用这些信息来检测不稳定和/或弱接触。探针由不同的通道共享，并且该共享配置由探针布置确定。因此，通道的基线波动和噪声与根据探针布置的探针的接触不稳定性和弱点有关。不稳定和/或弱探针通过求解该关系的逆问题来确定。使用所提出的方法可以有效地确定有问题的探头。
Multichannel functional near-infrared spectroscopy measurements involve the placement of many probes on a subject’s head. A stable close contact between the probe and head surface is essential. We propose a way to detect two types of problematic probe contacts from the measurement data: an unstable contact whose light transmission easily fluctuates with body motion, and a weak contact whose light transmission is constantly small. An unstable contact causes large baseline fluctuation, whereas a weak contact causes large noise. Because absorbance changes caused by body motion and noise show different spectroscopic properties from the tissue hemoglobin absorption, they have a component orthogonal to the plane spanned by hemoglobin molar extinction coefficient vectors. We use this information to detect unstable and/or weak contacts. Probes are shared by different channels, and this sharing configuration is determined by the probe arrangement. Thus, the baseline fluctuation and noise of the channels are related to contact instability and weakness of the probe according to the probe arrangement. Unstable and/or weak probes are determined by solving an inverse problem of this relation. Problematic probes can be effectively determined using the proposed method.