Early results on image and signal processing for characterization of blood flow in 4D MPI images

Our harmonic analysis has proven well suited to filter the MPI temporal signal and analytically reconstruct the behavior of the contrast product within a single averaged cardiac cycle. A sine-shaped temporal evolution of the signal is clearly visible within every voxel of a heart chamber, with more than ten times the amplitude of the background. The atrial and ventricular contraction and dilation behavior contribute to a periodic time signal with heart cycle periodicity. The streamlines of the ∇φ(p, t) vector field shown in figure 1 within the heart chambers may reveal an interesting velocity pattern. In view of the limited resolution of the current data, it is hard to separate the contributions of wall motion from flow in the v(p,t) maps. The large PSF of the system as compared with the heart chambers sizes hampers a reliable interpretation.