Hybrid photoacoustic and ultrasound tomography: ground truth validation (Conference Presentation)

The PAM3 breast imaging system enables photoacoustic and ultrasound tomography. The ultrasound mode creates 3D sound speed maps using time-of-flight tomography or a Full-Waveform Inversion framework. To evaluate the accuracy of our approach, we developed a well-characterized ground truth test object based on copolymer-in-oil gel. The sound speed for breast fatty tissue was mimicked with the base material; for mimicking breast glandular tissue, various additives such as glycerol were used. We characterized the tissue-type-mimics with independent measurements of the acoustic properties. We present details of the phantom, the image reconstruction algorithms, and discuss the sound speed images and photoacoustic images.