Non-contact measurement of zebrafish heartbeat guided by OCT imaging

The heart is the first organ to develop in zebrafish, and its developmental process is similar to that of the human heart. Zebrafish are an important model for studying human heart disease, and the accurate quantification of zebrafish heartbeats is instrumental in elucidating the intricacies of cardiac function and the pathogenesis of heart diseases, thereby facilitating a comprehensive understanding of potential therapeutic avenues. However, traditional methods such as electrocardiograph make it difficult to measure the heart rate of zebrafish in water. In this study, Optical Coherence Tomography (OCT) is employed to obtain high-precision images of the zebrafish heart area. These images are processed with an optical flow estimation algorithm to capture the motion information of the heart structure. Subsequently, a linear motion trajectory analysis algorithm is applied to fit waveforms to the extracted motion trajectories, enabling accurate computation of the zebrafish's heartbeat. The study demonstrates that this integrated approach enables high-precision, non-invasive measurement of zebrafish heartbeats, which can be used to monitor the changes in the zebrafish heartbeat induced by different anesthetic formulations.