Figure 5

(a) Velocity distribution in the patient-specific 3D geometries at the time of peak velocity in all three patients (PatID11, PatID13, PatID21 from top to bottom). Peak velocity, flow rate, and spatial distribution of the flow field differed between the three geometries. Pressure gradients listed in Table 3 were computed in the physical part of the aqueduct, i.e. as a linear approximation between the two slices depicted in red and yellow. (b) Volumetric flow rate (black curve) as a function of time also decomposed into its cardiac (orange) and respiratory (blue) component. A prominent respiratory component of the flow pattern is present. (c) Comparison of flow rates obtained with PC-MRI with the cardiac component of the flow rate computed from pressure driven flow in the patient-specific geometries. The good agreement is as expected, however in contrast to the simplified model, respiratory pressure gradients may slightly affect cardiac flow due to nonlinearities in Navier-Stokes equations.