Optically integrated trimodality imaging system: combined all-optical photoacoustic microscopy, optical coherence tomography, and fluorescence imaging.

We have developed a trimodality imaging system by optically integrating all-optical photoacoustic microscopy (AOPAM), optical coherence tomography (OCT), and fluorescence microscopy (FLM) to provide complementary information including optical absorption, optical back-scattering, and fluorescence contrast of biological tissue. By sharing the same low-coherence Michelson interferometer, AOPAM and OCT could be organically optically combined. Also, owing to using the same laser source and objective lens, intrinsically registered photoacoustic and fluorescence signals are obtained in a single pulse. Simultaneously photoacoustic angiography, tissue structure, and fluorescence molecular in vivo images of mouse ear were acquired to demonstrate the capabilities of the optically integrated trimodality imaging system, which can present more information to study tumor angiogenesis, vasculature, anatomical structure, and microenvironments in vivo.