为了在探测器数目有限的欠采样条件下提高三维光声重建图像的精度和空间分辨率，提出了一种基于结构先验信息加权的稀疏重建算法.利用待成像组织的结构先验信息对传统交替方向算法的迭代过程加以约束并对算法流程进行改进，将重建结果与最小平方QR分解法以及传统交替方向法进行对比.仿真实验结果表明，所提算法在欠采样条件下能够有效地抑制伪影，重建出空间分辨率和精度更高的三维光声图像.
Based on conventional alternating direction method (ADM), an advanced method called weighted ADM is proposed for three-dimensional photoacoustic reconstructions, to obtain better images with fewer measurements. Take advantage of structural information of targets as priori information, the iteration process of ADM is improved and optimized, and the reconstructed images were compared with the sparse equations and least squares methods (LSQR) and conventional ADM method. Simulation analysis showed that the proposed method is able to provide photoacoustic images with better accuracy and better spatial resolution in the circumstance of under-sampling, compared with the two other methods.
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