Indian Institute of Science, Department of Instrumentation and Applied Physics, Bangalore, Karnataka, India.
Nanyang Technological University, School of Chemical and Biomedical Engineering, Singapore, Singapore.
J Biomed Opt. 2021 Aug;26(8). doi: 10.1117/1.JBO.26.8.086004.
The proposed binary tomography approach was able to recover the vasculature structures accurately, which could potentially enable the utilization of binary tomography algorithm in scenarios such as therapy monitoring and hemorrhage detection in different organs.
Photoacoustic tomography (PAT) involves reconstruction of vascular networks having direct implications in cancer research, cardiovascular studies, and neuroimaging. Various methods have been proposed for recovering vascular networks in photoacoustic imaging; however, most methods are two-step (image reconstruction and image segmentation) in nature. We propose a binary PAT approach wherein direct reconstruction of vascular network from the acquired photoacoustic sinogram data is plausible.
Binary tomography approach relies on solving a dual-optimization problem to reconstruct images with every pixel resulting in a binary outcome (i.e., either background or the absorber). Further, the binary tomography approach was compared against backprojection, Tikhonov regularization, and sparse recovery-based schemes.
Numerical simulations, physical phantom experiment, and in-vivo rat brain vasculature data were used to compare the performance of different algorithms. The results indicate that the binary tomography approach improved the vasculature recovery by 10% using in-silico data with respect to the Dice similarity coefficient against the other reconstruction methods.
The proposed algorithm demonstrates superior vasculature recovery with limited data both visually and based on quantitative image metrics.
所提出的二进制层析成像方法能够准确地恢复血管结构,这可能使二进制层析成像算法能够在不同器官的治疗监测和出血检测等场景中得到应用。
光声断层扫描(PAT)涉及到具有直接影响的血管网络的重建,这在癌症研究、心血管研究和神经影像学中具有重要意义。已经提出了各种用于恢复光声成像中血管网络的方法;然而,大多数方法本质上是两步法(图像重建和图像分割)。我们提出了一种二进制 PAT 方法,其中从获得的光声正弦图数据直接重建血管网络是可行的。
二进制层析成像方法依赖于求解对偶优化问题,以重建每个像素都产生二进制结果(即背景或吸收体)的图像。此外,将二进制层析成像方法与反向投影、Tikhonov 正则化和基于稀疏恢复的方案进行了比较。
数值模拟、物理体模实验和体内大鼠脑血管数据用于比较不同算法的性能。结果表明,与其他重建方法相比,二进制层析成像方法在使用模拟数据时,血管恢复的 Dice 相似系数提高了 10%。
该算法在使用有限数据时,无论是在视觉上还是在基于定量图像指标上,都表现出了优越的血管恢复能力。