Abstract
Three-dimensional photoacoustic imaging of subcutaneous microvasculature in small animals is realized in vivo using photoacoustic microscopy. Previously, degraded lateral resolution in the out-of-focus region made three-dimensional visualization impractical. With the help of a virtual-detector synthetic aperture focusing technique, depth-independent lateral resolution is achieved. Therefore, volumetric imaging of the vessels is realized with a lateral resolution of 45 μm and an axial resolution of 15 μm. Detailed structural information, such as vessel depth and spatial orientation, are revealed with new clarity.