Spread Spectrum Photoacoustic Tomography With Image Optimization
Spread Spectrum Photoacoustic Tomography With Image Optimization
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DOI：
10.1109/tbcas.2016.2593470
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发表时间：
2017-04-01
影响因子：
5.1
通讯作者：
Carson, Paul L.
中科院分区：
文献类型：
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作者：
Cao, Meng;Feng, Ting;Carson, Paul L.
生物组织的光声层析成像（PAT）提供了潜在的优势，根据其化学成分区分不同的结构。然而，由于医学光声（PA）信号是宽带的，其通常覆盖0.2-50 MHz范围，因此当前的带限超声换能器只能接收和呈现该范围的有限部分。此外，接收到的PA信号通常具有低信噪比（SNR），这进一步恶化了图像质量。因此，这项工作的目标是恢复带外频率分量的基础上接收到的PA信号的超声换能器的频率响应的最佳估计，并提高PA图像质量。在此基础上，提出了一种基于逆滤波的信号恢复和多采样信号去噪相结合的方法，能够重建出更宽频带的声强信号，重建出信噪比更高的声强图像。通过这种方式，过去被隐藏在背景噪声中的详细信息被揭示出来，并且成像对象的边界被增强。进行了计算机模拟、体模实验和活体实验，并给出了重建图像。未来，我们的工作可以应用于临床和临床前生物医学成像领域，如多光谱PA成像、血管造影等相关领域。
Photoacoustic tomography (PAT) of biological tissue offers potential advantages in distinguishing different structures according to their chemical composition. However, as medical photoacoustic (PA) signals are broad band, which usually cover a 0.2-50 MHz range, current band-limited ultrasound transducers can only receive and present a limited fraction of that range. Besides, the received PA signals are usually of low signal-to-noise ratio (SNR), which further deteriorates the image quality. Therefore, the goal of this work is to recover the out-of-band frequency components in the received PA signals based on a best estimate of the frequency response of the ultrasound transducers, and to improve the PA image quality. Hereby, we came up with a method including signal recovery based on inverse filtering and multi-sampled signal de-noising, with which we were capable of rebuilding wider band PA signals and reconstructing PA images with higher SNR. In this way, detailed information that used to be buried in the background noise was revealed, and the boundaries of the imaging object were enhanced. Computer simulations as well as phantom and in vivo experiments were carried out and reconstructed images were given for illustration. In the future, our work can be applied to clinical and preclinical biomedical imaging fields, such as multi-spectrum PA imaging, angiography and other related fields.