Non-invasive measurement of thermal conductivity and thermal diffusivity of Rat liver

无创测量大鼠肝脏的热导率和热扩散率

基本信息

批准号：
13555056
负责人：
TAKAMATSU Hiroshi
金额：
$ 8.51万
依托单位：
Kyushu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

Thermophysical properties of biological materials are usually measured by using a thermal probe that is inserted into living tissues. Since a pool of blood and other fluids lay form around the probe because of mechanical trauma and it will significantly alter the result, a non-invasive technique is preferable for living tissues. The objective of this research was to develop a new technique to measure the thermal conductivity and the thermal diffusivity of biological materials, and to apply it to the rat liver.The temperature history of the specimen surface that was heated by a C0_2 laser was measured by an infrared thermometer. Both the thermal conductivity and the thermal diffusivity were determined from comparison of measured data with theoretical analysis of transient heat conduction for the same situation. One of the important points in the present technique was to exclude the effect of convection and radiation heat transfer on the temperature history.An acrylic resin block was chosen to check the validity of the present technique, and it was confirmed that the measured data agreed well with reference values. Then the present technique was applied to a rat liver. A SD rat was abdominally operated under anesthesia and the thermophysical properties of liver were measured in vivo. Appropriate data were obtained for a given value of absorption coefficient for the C0_2 laser, but the measured data depended largely on the absorption coefficient. Although more study is therefore needed to solve this problem, it was confirmed that the present technique was useful to clarify the effect of blood flow on the thermophysical properties.

生物材料的热物理特性通常通过使用插入活组织的热探针来测量。由于机械创伤导致探头周围形成一滩血液和其他液体，这会显着改变结果，因此非侵入性技术更适合活体组织。本研究的目的是开发一种测量生物材料热导率和热扩散率的新技术，并将其应用于大鼠肝脏。通过 CO_2 激光加热的样本表面的温度历史通过以下方法测量红外线温度计。热导率和热扩散率都是通过将测量数据与相同情况下的瞬态热传导理论分析进行比较来确定的。本技术的要点之一是排除对流和辐射传热对温度历史的影响。选择丙烯酸树脂块来检查本技术的有效性，并证实测量数据吻合良好有参考值。然后将本技术应用于大鼠肝脏。在麻醉下对SD大鼠进行腹部手术，并在体内测量肝脏的热物理特性。对于给定的CO_2激光器的吸收系数值，获得了适当的数据，但测量的数据很大程度上取决于吸收系数。尽管因此需要更多的研究来解决这个问题，但已证实本技术可用于阐明血流对热物理性质的影响。