The analysis of blood velocity measurements by autoregressive modelling.

Analysis of velocity disturbances arising in poststenotic flow is examined using the technique of autoregressive modeling. The essential elements of this method are described including relevant criteria for selecting the model order. Velocity data employed in the analysis are taken from in vivo measurements in the dog aorta, and the results indicate that the autoregressive method improves the resolution of coherent features in disturbed flow patterns. By applying homomorphic filtering to individual beats, the occurrence of organized structures convected from their origin in the shear layer is readily identified.