Development of a new instrument for non-invasive measurements of tissue (muscle) blood flow by near-infrared spectoroscopy.

我们建立了一种利用近红外光谱(NIRS)无创、连续测量血氧饱和度(STO_2)和血红蛋白绝对体积(Hb VOL)的方法。为了使用这种方法，设计了一种仪器(PSA-III N)，使组织表面可以连续地用三个波长的红外光照射，组织的散射光可以在距离照射部位一定距离的组织表面上测量。根据朗伯-比尔定律导出的方程，可从测量的吸光度中无创地确定组织中的ST O_2和Hb VOL的绝对值。PSA-III N中的Hb Vol值表示组织中Hb Vol或血液Vol的绝对值。因此，我们应用PSA-III n来测量肌肉血流量。通常，测量组织血流量的方法是静脉阻塞(60毫米汞柱)体积描记法。因此，我们使用PSA-III N通过静脉阻断(60 Mm Hg)来测量组织血流量。并与我们的PSA-III N静脉闭塞(60 Mm Hg)的测定值进行比较。本实验使用了8名男性受试者。每个受试者都进行了分级握手练习。采用常规静脉阻断法(60 Mm Hg)和PSA-III N静脉阻断法(60 Mm Hg)两种方法测定运动过程中肌肉血流量，共获得203个肌肉血流点。两种方法测得的血流量之间存在显著的相关性(r=0.60，p&lt；0.01)，说明该仪器(PSA-III N)提供了一种测量肌肉血流量的方法，在基础医学和临床医学中具有重要的应用价值。

We have developed a method of non-invasive and continuous measurements of oxygen saturation (St O_2) and absolute volumes of hemoglobin (Hb vol) using near-infrared spectroscopy (NIRS). An instrument (PSA-III N) has been designed for the use of this method so that the tissue surface can be irradiated successively with infrared light of three wavelengths, and the scattered light from the tissue can be measured on the tissue surface at a point a certain distance away from the irradiated site. St O_2 and absolute values of Hb vol in tissues can be non-invasively determined from the measured absorbance using equations derived from Lambert-beer's law. Values of Hb vol from PSA-III N show the absolute values of Hb vol or blood vol in tissue. So, we applied to measure muscle-blood flow using PSA-III N.In generally, to measure the tissue-blood flow is doing by method of venous occlusion (60mmHg) plethysmography. So, we measured the tissue-blood flow using PSA-III N by venous occlusion (60mmHg). And we compared the values between from the usual method of venous occlusion (60mmHg) plethysmography and from the our PSA-III N with venous occlusion (60mmHg). 8 male subjects were used in this experiment. Each subject was conducted a graded handgrip exercise. During the exercise, muscle blood flow were measured by two methods , i.e., the usual method of venous occlusion (60mmHg) plethysmography and the method of PSA-III N with venous occlusion (60mmHg).We got total 203 points of muscle blood flow with the two methods. And a significant correlation (r=0.60, p<0.01) was observed between values from two methods.From these results, we concluded that the instrument (PSA-III N) offers a means of measuring muscle blood flow, and may be very useful in basic and clinical medicine.