Estimation of two dimensional regional wall motion and two dimensional vector flow

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Conventional methods to evaluate regional wall motion need assumptios on the direction of wall motion such as motion toward the center of cavity, or the nearest points in the successive frame. However, actual wall motion includes cardiac rotation or more complicated motions and this actual motion may reflect cardiac conditions. Therefore we tried to track two dimensional wall motion without assumptions using high frame rate echocardiography (60 to 89 frame/sec) since defprmation of ventricular wall between two successive frames in high frame rate echo is expected to be small and this makes it easy to track images. We applied composite 2D correlation method, which uses appropriately weighted three indices, continuation of motion, cyclic change and large region of interest. The weight of each indices was determined by minimizing the accumulated squared errors from human tracing. We applied this method to another image and compared the result with simple correlation method, conventional methods with assumption on moving direction and conventional frame rate images. This composite method was the most accurate. This methods was applied to clinical diseases and detected wall motion revealed objectively disease specific wall motions. In the second research aim, we estimated two dimensional vector flow from conventional color Doppler image in ventricular cavity based on continuity equation. This result was examined with visualized 2D flow image by B-mode echo, injecting micro bubble and error derived from 3D flow was estimated computer simulation. This result is now in preparation for submission.