Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
Department of Physical Therapy, Niigata University of Health and Welfare, 1398 Shimami-cho, Kita-ku, Niigata-shi, Niigata, 950-3198, Japan.
Adv Exp Med Biol. 2013;789:97-103. doi: 10.1007/978-1-4614-7411-1_14.
Near-infrared spectroscopy (NIRS) is widely used to measure human brain activation on the basis of cerebral hemodynamic response. However, a limitation of NIRS is that systemic changes influence the measured signals. The purpose of this study was to clarify the relationship between NIRS signals and blood pressure during the Valsalva maneuver. Nine healthy volunteers performed a 20-s Valsalva maneuver to change their blood pressure. Changes in oxyhemoglobin (O2Hb) concentration were measured with 34 channels with an inter-optode distance of 30 mm for deep-penetration measurements (deepO2Hb) and 9 channels with an inter-optode distance of 15 mm for shallow-penetration measurements (shallowO2Hb). The difference value (diffO2Hb) between deepO2Hb and shallowO2Hb was calculated. Mean arterial pressure (MAP) was recorded by volume clamping the finger pulse, and skin blood flow changes were measured at the forehead. Pearson's correlation coefficients between deepO2Hb and MAP, shallowO2Hb and MAP, and diffO2Hb and MAP were 0.893 (P < 0.01), 0.963 (P < 0.01), and 0.831 (P < 0.01), respectively. The results suggest that regional and systemic changes in the cardiovascular state strongly influence NIRS signals.
近红外光谱（NIRS）广泛用于基于脑血流反应测量人类大脑激活。然而，NIRS 的一个限制是全身变化会影响测量信号。本研究旨在阐明 NIRS 信号与瓦尔萨尔瓦动作期间血压之间的关系。9 名健康志愿者进行了 20 秒的瓦尔萨尔瓦动作，以改变他们的血压。使用 34 个通道测量氧合血红蛋白（O2Hb）浓度，光极间距离为 30 毫米用于深度穿透测量（deepO2Hb），光极间距离为 9 毫米用于浅层穿透测量（shallowO2Hb）。计算 deepO2Hb 和 shallowO2Hb 之间的差值（diffO2Hb）。通过手指脉搏容积夹记录平均动脉压（MAP），并在前额测量皮肤血流变化。deepO2Hb 与 MAP、shallowO2Hb 与 MAP 以及 diffO2Hb 与 MAP 之间的 Pearson 相关系数分别为 0.893（P<0.01）、0.963（P<0.01）和 0.831（P<0.01）。结果表明，心血管状态的局部和全身变化强烈影响 NIRS 信号。
