Effects of Frequency and Number of Elements on Acoustic Fields Generated by a Spherical Ultrasound Phased Array Hyperthermia Applicator
Understanding the effect of frequency and number of elements on suppressing the grating lobes is of importance for the design of the phased array. In this study, acoustic field simulation model of a spherical phased array for focused ultrasound surgery is described. The influence on performance of frequency (0.8 to 1.5 MHz) and number of circular elements (45 to 90) in the array is investigated for elements distributed quasi-randomly on a spherical shell (radius of curvature, 180mm). The grating lobes and depth of focal region in the simulated acoustic fields are relatively sensitive to the increase of frequency. For a spherical phased array, decrease in frequency could suppress the grating lobes and enlarge the focused volume when focusing the array away from its center of curvature. For single focus pattern, a significant decrease in the number of elements could be made without degrading the quality of the intensity distribution. However, that could shift the focal region away from the array. The results of simulations offer useful suggestions for the optimization of the array to suppress the grating lobes and ablate the target tissue.
HIFU frequency number of elements grating lobes
Ji Xiang Shen Guo-feng Bai Jing-feng Chen Ya-zhu
Department of Biomedical Engineering Shanghai Jiao Tong University Shanghai,P.R.China
国际会议
北京
英文
1-3
2009-06-11（万方平台首次上网日期，不代表论文的发表时间）