Calculation of blood flow parameters in zebrafish larvae using the phase correlation method

Subject of the study. The parameters of the circulatory system of zebrafish model organisms in the larval stage were investigated. Aim of study. This study aimed to evaluate blood flow velocity in vessels of model organisms, namely, zebrafish (Danio rerio) larvae, using phase correlation methods when analyzing digital microscopy images. Methods. Noninvasive methods of digital microscopy are employed in zebrafish research tasks, enabling the high-speed acquisition of blood flow images. This study developed algorithms for processing acquired images to calculate blood flow parameters based on the phase correlation procedure. These algorithms involve the local matching of images with multiple reference frames, the creation of a synthesized vessel map, the determination of the trajectory of blood flow elements within the selected vessel, and the evaluation of blood flow velocity. Main results. A modified algorithm designed to estimate and compensate for local displacements in zebrafish images using multiple reference frames was developed. The algorithms based on the phase correlation method for calculating a synthesized map of zebrafish larval blood vessels, along with the trajectories and blood flow velocities within these vessels, were developed. These algorithms were verified through the processing of digital microscopy data from multiple zebrafish specimens. Through this verification, vessel maps, blood flow trajectories, and local blood flow velocity values for both arterial and venous vessels were obtained. Practical significance. This study developed algorithms for processing digital microscopy data to calculate the blood circulation system parameters of model organisms, such as zebrafish. The developed approaches can be used to study blood flow in tasks related to the testing of medicines or genetic studies.