Dynamic Mode Decomposition for Transient Cavitation Bubbles Imaging in Pulsed High Intensity Focused Ultrasound Therapy.
Dynamic Mode Decomposition for Transient Cavitation Bubbles Imaging in Pulsed High Intensity Focused Ultrasound Therapy.
复制标题
脉冲高强度聚焦超声治疗中瞬态空化气泡成像的动态模式分解。
DOI：
10.1101/2024.02.26.582222
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发表时间：
2024
期刊：
影响因子：
--
通讯作者：
Khokhlova,TatianaD
中科院分区：
文献类型：
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作者：
Song,Minho;Sapozhnikov,OlegA;Khokhlova,VeraA;Khokhlova,TatianaD
脉冲高强度聚焦超声（pHIFU）可以在不引入外源性造影剂的情况下诱导稀疏的从头惯性空化，促进靶组织中的轻度机械破坏。由于气泡很小并且在每次HIFU脉冲后迅速溶解，因此映射瞬态气泡并获得与组织损伤相关的实时定量度量是具有挑战性的。先前的工作介绍了气泡多普勒，超快功率多普勒成像方法作为一种敏感的手段来映射空化气泡。该方法的主要局限性是它依赖于多普勒成像中使用的传统壁滤波器，以及它对血流而不是瞬态散射体成像的优化。本研究探讨气泡多普勒增强使用动态模式分解（DMD）的矩阵创建的多普勒合奏映射和提取的瞬态空化气泡的特性。DMD首先在计算机中进行测试，数值数据集模拟来自组织和气泡的反向散射信号的时空特征。比较了DMD滤波器与其他常用的多普勒壁滤波器-奇异值分解（SVD）和无限冲激响应（IIR）高通滤波器的性能。然后将DMD应用于离体组织数据集，其中每个HIFU脉冲之后立即是平面波多普勒集合。计算机模拟DMD优于SVD和IIR高通滤波器，并且离体提供了与气泡及其相应的时间衰减率相关的模式的物理可解释图像。这些DMD模式可以在pHIFU治疗的持续时间内使用k均值聚类方法进行跟踪，从而产生治疗进展的定量指标。
Pulsed high-intensity focused ultrasound (pHIFU) can induce sparse de novo inertial cavitation without the introduction of exogenous contrast agents, promoting mild mechanical disruption in targeted tissue. Because the bubbles are small and rapidly dissolve after each HIFU pulse, mapping transient bubbles and obtaining real-time quantitative metrics correlated with tissue damage are challenging. Prior work introduced Bubble Doppler, an ultrafast power Doppler imaging method as a sensitive means to map cavitation bubbles. The main limitation of that method was its reliance on conventional wall filters used in Doppler imaging and its optimization for imaging blood flow rather than transient scatterers. This study explores Bubble Doppler enhancement using dynamic mode decomposition (DMD) of a matrix created from a Doppler ensemble for mapping and extracting the characteristics of transient cavitation bubbles. DMD was first tested in silico with a numerical dataset mimicking the spatiotemporal characteristics of backscattered signal from tissue and bubbles. The performance of DMD filter was compared to other widely used Doppler wall filter-singular value decomposition (SVD) and infinite impulse response (IIR) high-pass filter. DMD was then applied to an ex vivo tissue dataset where each HIFU pulse was immediately followed by a plane wave Doppler ensemble. In silico DMD outperformed SVD and IIR high-pass filter and ex vivo provided physically interpretable images of the modes associated with bubbles and their corresponding temporal decay rates. These DMD modes can be trackable over the duration of pHIFU treatment using k-means clustering method, resulting in quantitative indicators of treatment progression.