在模仿头骨的数字幽灵中,声音的速度取决于微观结构
Samuel Clinard1,2, Taylor Webb2, Henrik Odéen2
1Department of Biomedical Engineering, University of Utah, Salt Lake City, UT, United States of America.
Physics in medicine and biology
|November 3, 2025
概括
头骨的微观结构显著影响了超声波的聚焦,影响了跨的聚焦超声波疗法. 了解这些变异对于改善治疗精度和安全性至关重要,在应用中,如组织缩和神经调节.
科学领域:
- 超声波物理学的超声波物理
- 生物医学工程 生物医学工程
- 医学成像医学成像
背景情况:
- 跨的聚焦超声波 (FUS) 疗法需要精确的超声波束通过头骨聚焦.
- 计算机断层扫描 (CT) 用于相位偏差校正,但其分辨率限制了准确性.
- 未解决的骨微观结构引入了骨声学属性的不确定性,降低了FUS聚焦精度.
研究的目的:
- 为了研究骨微观结构对超声速的影响.
- 量化毛孔大小和毛孔度如何影响骨幻象中的组和相速.
- 为了突出CT衍生声学特性在FUS应用中的局限性.
主要方法:
- 模拟超声波通过传输测量使用k-Wave软件.
- 数字幻影模仿皮质骨,具有不同的多孔度 (0-80%) 和毛孔大小 (0.1-0.6毫米).
- 在多个频率 (250 kHz到1 MHz) 上模拟脉冲和连续平面源.
主要成果:
- 超声波速度 (组和阶段) 随着孔径和孔隙性而有显著变化.
- 较小的毛孔导致较快的速度,相比较较大的毛孔在相同的多孔度.
- 稳定状态相变量随着孔径和频率的增加而增加,表明微观结构的依赖.
结论:
- 由于未解决的微观结构,CT霍恩斯菲尔德单位 (HU) 提供了与声速的不确定关系.
- 速度的变化影响着脉冲式 (组织缩) 和连续性 (神经调节,热切除菌) FUS应用.
- 考虑到骨微观结构对于提高跨骨FUS治疗的安全性和有效性至关重要.
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