高质量的被动声学映射与交叉相关角光谱方法
概括
一种新的交叉相关角频谱方法 (AS-TAX) 能够实时进行高质量的被动声学映射,用于聚焦超声疗法. 这种技术有效地抑制了文物和地图的化活动,提升了监控能力.
科学领域:
- 生物医学工程 生物医学工程
- 声学成像 声学成像
- 聚焦超声波疗法 聚焦超声波治疗
背景情况:
- 被动声学映射 (PAM) 对于在聚焦超声波 (FUS) 治疗中监测声学腔位至关重要.
- 目前的方法,如角光谱 (AS) 方法,面临着文物和低分辨率的挑战.
- 数据适应式光束构造器提供了良好的文物抑制,但对于实时应用程序而言,其计算复杂性过高.
研究的目的:
- 开发一种实时,高质量的被动声学映射方法,用于聚焦超声疗法.
- 解决现有方法的局限性,特别是工件减少和计算效率.
- 为了能够精确监测FUS治疗期间的声腔活动.
主要方法:
- 引入交叉相关角光谱 (AS) 方法,利用从子孔口反向传播的波场的交叉相关性.
- 开发与AS (AS-TAX) 交叉相关 (TAX) 的三重apodization方案,以实现最佳的文物抑制.
- 通过幻影实验和体内小鼠瘤研究的验证.
主要成果:
- 与时间曝光声学 (TEA) 方法相比,AS-TAX方法的图像质量与数据适应性光束造型器相比,显著降低了能量传播,并改善了信号与噪声的比率.
- 与TEA相比,AS-TAX显示了计算复杂性的两级降低,使得毫秒级图像重建成为可能.
- 该方法准确地绘制了微气泡化活动的地图,区分了稳定和惯性状态.
结论:
- 该AS-TAX方法为FUS治疗的被动声学映射提供了显著的进步.
- 它提供了实时,高质量的成像解决方案,用于监测洞穴活动.
- 这种技术有可能提高基于空腔的FUS治疗的安全性和有效性.
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