基于离散随机介质平均散射声功率的无损测温方法

Noninvasive temperature estimation in biotissue as a discrete random medium based on backscattered average ultrasonic power

生物组织中超声散射回波的平均功率与其温度有关．该理论包含：（１）生物组织近似为离散随机介质．（２）离散随机介质的平均散射功率与组织的衰减系数α和声速Ｃ有关。对于似水生物组织（如：猪肝），当温度升高时，衰减系数的减小使平均散射声功率增加，但其影响大小与时间窗△ｔ有关，而声速的增大则使平均散射声功率减小。实验结果表明：生物组织的平均散射声功率随温度变化趋势明显，该结果提供一种肿瘤热疗无损伤检测温度的新方法。

The backscattered average ultrasonic power of biotissue is related to its temperature.This theory includes (1) the model of discrete random medium is considered with biotissue. (2) the average backscattered ultrasound power depends on the attenuation and velocity in biotissue. Theoretical analysis indicates: to an aqueous scatterer in a water-based medium(e.g.pig liver), when temperature increased, backscattered average ultrasonic power increased with attenuation while decreased with the ultrasound velocity. Experimental result shows: the average backscattered power is changed with temperature obviously and can be measured. Based on this result, a new noninvasive temperature estimation method is advanced and confirmed here.