Development of ultrasound echocardiography technique for imaging of the cardiovascular system of small organisms in vivo

A technique based on a high-frequency ultrasound scanner was developed for imaging and characterization of the cardiovascular system of small organisms in vivo. An optical microscope combined with the ultrasonic unit was used in the experimental setup for simultaneous recording ultrasonic signals and video data. It was shown that combination of optical and ultrasonic data is effective to visualize dynamic processes in a living object. In addition to imaging of the cardiovascular system, video data was processed to estimate the period and phase of the cardiac cycle and to generate a trigger signal for the ultrasonic unit. The proposed approach and developed experimental setup were applied to imaging of the Danio rerio larva. In a result of the processing of the synchronous ultrasonic and optical data, the blood flow in the heart of the larva and the movement of surrounding organs were observed.