Kuriyama N
Department of Public Health, School of Medicine, Kanazawa University.
Nihon Eiseigaku Zasshi. 1990 Jun;45(2):688-99. doi: 10.1265/jjh.45.688.
In order to assess tissue blood flow quantitatively under various temperature conditions, we have developed a new blood-flow measurement apparatus based on the thermal diffusion method. This new method is hardly affected by environmental temperature, by means of using the thermal clearance curve with its baseline corrected before each measurement. Fundamental studies concerning the measurement of human skin blood flow were carried out in the finger. The results obtained were as follows. 1) The gradient of the thermal clearance curve did not show significant changes under various temperature conditions. This result indicated that the effects of environmental temperature on the thermal clearance curve were almost removed. 2) A highly positive correlation was obtained between the thermal conductivity of various materials similar to human skin in thermal conductivity and the gradient of the thermal clearance curve from a probe placed on a plate of each material. 3) There was linear relationship between the water flow and the gradient of the thermal clearance curve in various water flows of a micro-circulation model. The gradient of the thermal clearance curve obtained for each water flow had good reproducibility. 4) The gradient of the thermal clearance curve changed in parallel with the finger ischemia and hyperemia induced by inflation of a tourniquet. There was good reproducibility in continuous measurements. 5) A highly significant positive correlation was obtained between finger blood flow measured by the inhaled hydrogen clearance method and the gradient of the thermal clearance curve, indicating that it was possible to assess finger blood flow quantitatively by the gradient of the thermal clearance curve. The weak point in the former thermal diffusion method, where the baseline was unstable as a result of environmental temperature, was removed. It was concluded that this new thermal diffusion method using the thermal clearance curve, which was calibrated previously by the hydrogen clearance method, enabled us to measure finger blood flow noninvasively at various temperatures. This method will be useful for diagnosis and research in various medical fields.
为了定量评估各种温度条件下的组织血流，我们基于热扩散法开发了一种新的血流测量装置。这种新方法通过在每次测量前校正基线的热清除曲线，几乎不受环境温度的影响。在手指上进行了关于人体皮肤血流测量的基础研究。获得的结果如下。1）热清除曲线的斜率在各种温度条件下没有显示出显著变化。该结果表明环境温度对热清除曲线的影响几乎被消除。2）在热导率与人体皮肤相似的各种材料的热导率和放置在每种材料平板上的探头的热清除曲线斜率之间获得了高度正相关。3）在微循环模型的各种水流中，水流与热清除曲线斜率之间存在线性关系。为每种水流获得的热清除曲线斜率具有良好的重现性。4）热清除曲线斜率与通过止血带充气诱导的手指缺血和充血平行变化。连续测量具有良好的重现性。5）通过吸入氢气清除法测量的手指血流与热清除曲线斜率之间获得了高度显著的正相关，表明可以通过热清除曲线斜率定量评估手指血流。以前热扩散法中由于环境温度导致基线不稳定的弱点被消除了。得出的结论是，这种使用预先通过氢气清除法校准的热清除曲线的新热扩散法使我们能够在各种温度下无创地测量手指血流。这种方法将对各种医学领域的诊断和研究有用。
