A Demonstration of Errors in Relative Pressure Calculations from MR Velocity Data
نویسنده
چکیده
Introduction Relative pressure maps may be calculated from MRI velocity images on a voxel-by-voxel basis using the Navier-Stokes equation [1] to calculate the pressure gradient and numerical integration to generate a relative pressure map [3]. We show the accuracy of the derived pressure maps to be very sensitive to imaging noise and partial volume effects, both of which undermine the fluid dynamical assumptions associated with the Navier-Stokes formulation. We present here the results of numerical simulations of these error sources in a simple hydrodynamic system and suggest a method for reducing the impact of partial volume effects on the derived pressure map.
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