Location-Dependent Spatiotemporal Antialiasing in Photoacoustic Computed Tomography
Location-Dependent Spatiotemporal Antialiasing in Photoacoustic Computed Tomography
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DOI：
10.1109/tmi.2022.3225565
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发表时间：
2022-11
影响因子：
10.6
通讯作者：
Peng Hu;Lei Li;Lihong V. Wang
中科院分区：
文献类型：
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作者：
Peng Hu;Lei Li;Lihong V. Wang
光声计算机断层扫描 (PACT) 通过检测生物组织等材料中光能沉积引起的超声波来成像光吸收对比度。超声换能器阵列或其扫描等效物用于检测超声波。换能器元件的空间分布必须满足空间奈奎斯特准则；否则，会发生空间混叠并导致重建图像中出现伪影。空间奈奎斯特准则对图像域中不同位置的换能器元件的分布提出了不同的要求，这在以前没有被研究过。在本研究中，我们通过时空分析详细阐述了位置依赖性，并提出了一种位置相关的时空抗锯齿方法。通过将此方法应用于全环阵列几何结构中的 PACT，我们可以有效地减轻混叠伪影，同时在数值模拟和体内实验中对图像分辨率的影响最小。
Photoacoustic computed tomography (PACT) images optical absorption contrast by detecting ultrasonic waves induced by optical energy deposition in materials such as biological tissues. An ultrasonic transducer array or its scanning equivalent is used to detect ultrasonic waves. The spatial distribution of the transducer elements must satisfy the spatial Nyquist criterion; otherwise, spatial aliasing occurs and causes artifacts in reconstructed images. The spatial Nyquist criterion poses different requirements on the transducer elements’ distributions for different locations in the image domain, which has not been studied previously. In this research, we elaborate on the location dependency through spatiotemporal analysis and propose a location-dependent spatiotemporal antialiasing method. By applying this method to PACT in full-ring array geometry, we effectively mitigate aliasing artifacts with minimal effects on image resolution in both numerical simulations and in vivo experiments.