Space-invariant true-velocity flow mapping using coplanar observations
The diagnostic value of the current two-dimensional Doppler flow mapping techniques is limited by the fact that velocity values at different parts of the image are only projections of the total three-dimensional true-velocity vectors onto the image plane. Since these vectors have different orientations, the resulting values do not have the same reference and hence cannot be compared for correct diagnosis. Here, the authors show that it is possible to obtain true-velocity flow maps from coplanar observations. This effectively eliminates any angle dependency in the imaging process and provides a convenient way of representing velocity as a two-dimensional map relative to the same reference. Also, the authors establish the conditions under which this estimation process is space invariant to illustrate the practicality of the technique.