For many optical imaging modalities, image qualities are inevitably degraded by wavefront distortions caused by varying light speed. In optical microscopy and astronomy, adaptive optics (AO) has long been applied to compensate for such unwanted aberrations. Photoacoustic computed tomography (PACT), despite relying on the ultrasonic wave for image formation, suffers from the acoustic version of the same problem. However, this problem has traditionally been regarded as an inverse problem of jointly reconstructing both the initial pressure and the sound speed distributions. In this work, we proposed a method similar to indirect wavefront sensing in AO. We argued that wavefront distortions can be extracted and corrected by a frequency domain analysis of local images. In addition to an adaptively reconstructed aberration-free image, the speed of sound map can be subsequently estimated. We demonstrated the method by in silico, phantom, and in vivo experiments.

对于许多光学成像模式，由于光速变化引起的波阵面畸变不可避免地降低了图像质量。在光学显微镜和天文学中，自适应光学（AO）长期以来一直用于补偿这种不希望有的像差。尽管依靠超声波进行图像形成，但是光声计算机断层扫描（PACT）遭受了相同问题的声学影响。然而，传统上，该问题被认为是联合重建初始压力和声速分布的反问题。在这项工作中，我们提出了一种类似于AO中间接波前感测的方法。我们认为可以通过对局部图像进行频域分析来提取和校正波前畸变。除了自适应重建的无像差图像外，声图的速度可以随后估计。我们通过演示了该方法在计算机，幻像和体内实验中进行。