组织温度的无创监测是微波消融技术应用中的一项难题,探讨利用B超图像纹理特征实现微波消融温度监测的可行性。通过微波消融离体猪肝实验,采集不同温度下的B超图像;在此基础上,分析数字减影图像的纹理特征参数(灰度直方图和灰度共生矩阵)与温度的相关性。实验结果表明:组织B超图像纹理参数随着温度变化而变化,在15-90℃范围内图像灰度均值、灰度熵、角二阶矩等与组织温度间具有近似线性关系;利用这种相关性,可实现肿瘤微波消融治疗中组织温度的无创检测。
The noninvasive estimation of tissue temperature is a key problem in microwave ablation. This study is aimed to investigate the feasibility of temperature monitoring with B-mode ultrasound texture. The experiments were carried out on in vitro porcine liver samples heated by microwave ablation, and the B-mode ultrasound images at various temperatures were analyzed. Then the relationship between temperature and texture of digital differential image such as gray level histogram and gray level co-occurrence matrices were analyzed. The results indicated that some parameters varied in accordance with the temperature changes in the heated tissue. Mean gray scale (MGS), entropy (ENT) and angular second moment (ASM) presented approximately linear relation with the temperature. All these showed the feasibility of this noninvasive technique in noninvasive estimation of tissue temperature.