Visualization: Cardiovascular blood flow analysis

This project analyses blood flow data from direct measurements (4D flow MRI). A clustering approach has been developed based on 2D coherence maps placed in the in- and outflow areas, which summarize the flow behavior of the 3D volume. Thereby coherence is defined on the basis of the Finite-time Lyapunov Exponent (FTLE), which measures the rate of separation of pathlines originating from the map. The coherence map serves as basis for the automatic extraction of a small number of representative pathline. For a further flow exploration the extracted clusters can be selected and inspected individually. Switching off clusters reduces the amount of occlusion and reveals the remaining part of the flow. Characteristically measures like the flow rate of the clusters and cluster coherence provide a measure for their significance.