Photoacoustic tomography has great potential to image dynamic functional changes in vivo. Many tomographic systems are built with a circular view geometry, necessitating a linear translation along one axis of the subject to obtain a three-dimensional volume. In this work, we evaluated a prototype spherical view photoacoustic tomographic system which acquires a 3D volume in a single scan, without linear translation. We simultaneously measured relative hemoglobin oxygen saturation in multiple placentas of pregnant mice under oxygen challenge. We also synthesized a folate-conjugated indocyanine green (ICG) contrast agent to image folate kinetics in the placenta. Photoacoustic tomography performed at the wavelength of peak optical absorption of our contrast agent revealed increased ICG signal over time. Through these phantom and in vivo studies, we have demonstrated that the spherical view 3D photoacoustic tomographic system achieves high sensitivity and fast image acquisition, enabling in vivo experiments to assess physiological and molecular dynamics.

光声层析成像在体内动态功能变化方面具有巨大潜力。许多断层扫描系统都具有圆形视图几何形状，因此必须沿对象的一个​​轴进行线性平移才能获得三维空间。在这项工作中，我们评估了原型球形视图光声层析成像系统，该系统在一次扫描中无需线性平移即可获取3D体积。我们同时测量了富氧挑战下怀孕小鼠的多个胎盘中的相对血红蛋白氧饱和度。我们还合成了叶酸共轭吲哚菁绿（ICG）造影剂，以成像胎盘中的叶酸动力学。在我们的造影剂的峰值光吸收波长处进行的光声层析成像显示，随着时间的流逝，ICG信号增加。通过这些幻影和体内研究表明，球形3D光声层析成像系统可实现高灵敏度和快速图像采集，从而使体内实验能够评估生理和分子动力学。