X-ray-induced acoustic computed tomography (XACT) is a promising imaging modality combining high X-ray absorption contrast with the 3-D propagation advantages provided by high-resolution ultrasound waves. The purpose of this study was to optimize the configuration of a 3-D XACT imaging system for bone imaging. A 280 ultrasonic sensors with peak frequency of 10 MHz was designed to distribute on a spherical surface to optimize the 3-D volumetric imaging capability. We performed both theoretical calculations and simulations of this optimized XACT imaging configuration on a mouse-sized digital phantom containing various X-ray absorption coefficients. Iteration algorithm based on total variation has been used for 3-D XACT image reconstruction. The spatial resolution of imaging was estimated to about $130~\mu \text{m}$ along both axial and lateral directions. We simulate XACT imaging of bone microstructures using digital phantoms generated from micro-CT images of real biological samples, showing that XACT imaging can provide high-resolution imaging of the mouse paw. Results of this study will greatly enhance the potential of XACT imaging in the evaluation of bone diseases for future clinical use.

中文翻译：

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具有球形阵列的3-D X射线诱导的声学计算机断层扫描：骨成像的模拟研究。

X射线诱导声学计算机断层扫描（XACT）是一种很有前途的成像方式，将高X射线吸收对比度与高分辨率超声波提供的3-D传播优势相结合。这项研究的目的是优化用于骨骼成像的3-D XACT成像系统的配置。设计了峰值频率为10 MHz的280个超声波传感器，以分布在球形表面上，以优化3-D体积成像功能。我们对包含各种X射线吸收系数的鼠标大小的数字体模进行了这种优化XACT成像配置的理论计算和模拟。基于总变化量的迭代算法已用于3-D XACT图像重建。成像的空间分辨率估计约为 $ 130〜\ mu \ text {m} $ 沿轴向和横向。我们使用从真实生物样品的微CT图像生成的数字体模模拟骨骼微结构的XACT成像，表明XACT成像可以提供小鼠爪的高分辨率成像。这项研究的结果将大大增强XACT成像在评估骨病以供将来临床应用方面的潜力。