Shaihan J Malik1, Alessandro Sbrizzi2, Hans Hoogduin2, and Joseph V Hajnal1
1Imaging Sciences & Biomedical Engineering, King's College London, London, United Kingdom, 2Imaging Division, University Medical Centre, Utrecht, Utrecht, Netherlands
Extended Phase Graphs and Isochromat-summation
are two leading methods for simulating MR signals. The latter method is more
intuitive, but choice of the number and distribution of isochromats
significantly affects results. It is well known that the two methods are
related by Fourier Transform, but precise equivalence is not widely understood.
We demonstrate conditions under which they are exactly equivalent and related
by DFT. Choice of isochromats is shown to be a sampling problem and conditions
for accurate isochromat-based simulations are given. Matlab code is provided as a direct
illustration.
