In vivo blood flow visualization with magnetic resonance imaging

Blood movement investigated by magnetic resonance (MR) velocity mapping is generally presented in the form of velocity components in one or more chosen velocity encoding directions. By viewing these components separately, it is difficult for MR practitioners to conceptualize and comprehend the underlying flow structures, especially when the image data have strong background noise. A flow visualization technique that adapts the idea of particle tracing used in classical fluid dynamics for visualizing flow is presented. The flow image processing relies on the strong correlation between the principal flow direction estimated from the distribution of the modulus of the velocity field and the direction derived from the raw image data. By correlation calculation, severe background noise can be eliminated. Flow pattern rendering and animation provide an efficient way for representing internal flow structures