COMPUTATIONAL BLOOD-FLOW MODELING - ERRORS ASSOCIATED WITH RECONSTRUCTING FINITE-ELEMENT MODELS FROM MAGNETIC-RESONANCE IMAGES

Construction of computational blood flow models from magnetic resonanc e (MR) scans of real arteries is a powerful tool for studying arterial hemodynamics. In this report we experimentally determine a lower boun d for errors associated with such an approach, and present techniques for minimizing such errors. A known, simple three-dimensional geometry (cylindrical tube) was imaged using a commercial MR scanner, and the resulting images were used to construct finite element flow models. Co mputed wall-shear stresses were compared to known values and peak erro rs of 40-60% were found. These errors can be attributed to limited spa tial resolution, image segmentation and model construction. A simple s moothing technique markedly reduced these peak errors. We conclude tha t smoothing is required in the construction of arterial models from in vivo MR images. If used appropriately, such images can be used to con struct acceptably accurate computational models of realistic arterial geometries. (C) 1998 Elsevier Science Ltd. All rights reserved.