A MULTIRESOLUTION APPROACH TO FLOW FEATURE EXTRACTION FROM PHASE CONTRAST MAGNETIC RESONANCE ANGIOGR - Multiresolution Modelling and Analysis in Image Processing and Computer Vision, IEE Colloquium on

Magnetic resonance imaging (BARI) is used to map the distribution and dynamics of nuclei such as hydrogen. Imaging can be adapted to shalw blood in contrast to the surrounding sationary tissues. This application of MRI referred to as MR angiography @IRA) has become widely used in cardiovascular assessment beciiuse of its sensitivity to disease states and lack of ionising radiation or iodinated contrast agent. The two main classes of MRA techniques use blood’s motion to modify the intensity Time of Flight techniques) or phase (Phase Contrast techniques) of the blood signal relative to that of static tissues. Time of Flight techniques are most widely available, but have severe limitations in terms of robustness of the quantifiable relationship. Phase constrast angiography (ITA) produces a vector image i.e. estimates are formed of three orthogonal components of the velocity fielld. In effect, not one, but four images are obtained a T1-weighted anatomical image, and three images of orthogonal velocity components.