Estimation of relative cardiovascular pressures using time-resolved three-dimensional phase contrast MRI

Accurate, easy-to-use, noninvasive cardiovascular pressure registration wou ld be an important addition to the diagnostic armamentarium for assessment of cardiac function. A novel noninvasive and three-dimensional (3D) techniq ue for estimation of relative cardiovascular pressures is presented. The re lative pressure is calculated using the Navier-Stokes equations along user- defined lines placed within a time-resolved 3D phase contrast MRI dataset. The lines may be either straight or curved to follow an actual streamline. The technique is validated in an in vitro model and tested on in vivo cases of normal and abnormal transmitral pressure differences and intraaortic fl ow. The method supplements an intuitive visualization technique for cardiov ascular flow, 3D particle trace visualization, with a quantifiable diagnost ic parameter estimated from the same dataset, (C) 2001 Wiley-Liss, Inc.