Brian Andrew Hargreaves1,
Karla L. Miller2
1Radiology,
Stanford University, Stanford, CA, United States; 2FMRIB Centre,
Oxford University, Oxford, United Kingdom
The extended-phase-graph (EPG) formalism, which allows efficient simulation of the signal from numerous commonly-used pulses sequences, is rized intuitively, with example applications and software. EPG treats a group of spins within a voxel undergoing integer numbers of cycles of gradient dephasing by using a Fourier basis that reduces a large spin ensemble to a limited number of states. Effects of relaxation, RF nutation, gradient dephasing and rephasing, diffusion and static dephasing are easily included. Links to Matlab code with intuitive examples of how to build up pulse sequence simulations are provided.