Linked geometric features for modeling the fluid flow in developing embryonic vertebrate hearts

The embryonic vertebrate heart starts pumping long before the formation of valves and chambers. Zebrafish embryonic hearts are morphologically comparable to human embryonic hearts in early stage. Since they are optically transparent, they are of obvious scientific use to study the beating heart. This paper proposes a fast and reliable algorithm based on tracking of linked geometric features to derive the motion of the heart walls and the velocity in the fluid flow. In contrast to active contour methods, we model the heart walls with parabola segments. This is both simpler and accurate enough to model heart walls. An original contribution in this paper is that we can track the heart walls and the blood cells using the same method and provide consistent estimates of both. Moreover, due to the pumping mechanism of the heart, the tracking of the heart walls is used to determine the region of interest for the tracking of the blood cells. This relation decreases the false matches of blood cells by more than 50%, which results in a much improved estimation of the velocity in the fluid flow.