血管对HIFU治疗焦域影响的实验研究

通过实验测量高强度聚焦超声辐照下仿组织体模中焦域附近特定点的温度变化以及形成焦域大小分析血管对HIFU治疗焦域的影响.当血管位置和血流速度分别不同时利用热电偶探针测量几何焦点上方2 mm处温度，采用Matlab编程计算焦域体积.在血管前方聚焦时，焦域附近峰值温度较高，形成焦域体积较大；在血管后方聚焦时，焦域体积随远离血管距离的增大而增大；无血流时，焦域附近峰值温度较高，焦域体积较大；加入血流之后，焦域附近峰值温度明显降低，但血流速度差异性对峰值温度和焦域大小影响不明显.血管位置和血流速度影响HIFU治疗焦域温度分布，在临床治疗焦域附近有血管时应当考虑血管的影响.

Experimental Study of the Effect of Blood Vessel on High Intensity Focused Ultrasound Focal Region

Temperature of a given point near focal region and the size of focal region were measured to study the effect of blood vessel on high intensity focused ultrasound focal region.Blood vessel location and blood flow velocity were varied and the thermocouple probe was inserted vertically to the sound axis into the tissue phantom.After experiment,the size of focal region was calculated by Matlab.Temperature was getting higher and the focal region wass getting bigger when focus was far from blood vessel.The temperature when there was no blood flow near the focal region obviously lower than that when there was blood flow.But when the blood flow velocity was varied,the change of temperature and the size of focal region was not obvious.The blood vessel location and blood flow velocity have effect on temperature distribution of focal region for high intensity focused ultrasound,and blood vessel should be considered when the focal region was close to blood vessel in the clinical treatment.