Fig. 2.

Separation of respiratory and cardiac signal changes in the SVD of a typical human cardiac MR dataset. The Casorati matrix was created from data measured at a limited number of k-space locations. The figure plots the real parts of v₂ and v₁₈, respectively. Both vectors are complex, but only the real parts are shown for the purposes of simplicity. As can be seen, v₂ contains the low-frequency signal changes (related to respiratory motion), whereas v₁₈ captures faster cardiac motion.