Breast tumor appearances in photoacoustic tomography from fine 3D optical-acoustic simulations (Conference Presentation)

Photoacoustic breast imaging has been under development for more than a decade now, and is progressively moving towards the clinics to investigate its performance in tumor detection and diagnosis. Several system types have been built, all with their own characteristics and corresponding imaging performances. Different studies have observed variations in tumor appearances. Some works have seen peripheral blood vessels in the tumor region, while others showed mass-like appearances at the tumor site. These varying tumor presentations may be caused by the deviations in system characteristics, but can also be caused by anatomical differences of the tumors. While we can still learn a lot from in-vivo studies, accurate simulation studies are needed to understand the tumor appearances in full detail. We have developed a simulation toolbox to perform 3D full breast photoacoustic simulations. To investigate the tumor appearance, several tumor models are embedded inside a MRI-segmented digital breast phantom [Y. Lou et al (2017)], which is pendant in a hemispherical imaging tank filled with water. Illumination fibers and US detectors are placed on the surface of the imaging bowl. The toolbox easily allows to adjust laser and detector characteristics. Illumination of the breast is simulated with GPU-accelerated Monte Carlo simulations [Q. Fang et al. (2009)]. The subsequent acoustic signal generation and propagation is modeled with k-wave (GPU-accelerated, [B.E. Treeby et al. (2010)]). Finally, images are reconstructed to evaluate the tumor appearance.