Realtime photoacoustic microscopy of murine cardiovascular dynamics.

Non-invasive visualization of cardiovascular dynamics in small animals is challenging due to their rapid heart-rates. We present a realtime photoacoustic imaging system consisting of a 30-MHz ultrasound array transducer, receive electronics, a high-repetition-rate laser, and a multicore-computer, and demonstrate its ability to image optically-absorbing structures of the beating hearts of young athymic nude mice at rates of approximately 50 frames per second with 100 microm x 25 microm spatial resolution. To our knowledge this is the first report of realtime photoacoustic imaging of physiological dynamics.