Two methods of simulating the imaging process in magnetic resonance (MR) ar
e explained: namely, the k-space and the isochromat summation methods. The
latter method is more closely related to the actual behavior of magnetic sp
ins, and is used in the remainder of this work. The MR image appearance of
in-plane fluid flow is simulated using the isochromat summation technique.
Flow-related artifacts are demonstrated, together with flow compensation, p
hase-contrast (PC) velocity encoding. and cine-PC measurement of pulsatile
flow. The special considerations necessary for simulating pulsatile flow wi
th a reverse flow component are discussed. Magnetic held inhomogeneities an
d susceptibility effects are readily incorporated. The computation time req
uired for the simulations is discussed in some detail. Simulations of flow
imaging have been found useful in the development and validation of new pul
se sequences, and for teaching purposes. (C) 1999 John Wiley & Sons, Inc.