Fast Gradient Echo Sequences Including Balanced SSFP

Many common magnetic resonance imaging sequences are classified either as spin echo or gradient echo techniques. Generally, a gradient echo occurs when spins are coherent regardless of their position within the sample. This occurs whenever the net gradient area since a previous echo is zero. In a spin echo, spins are coherent regardless of their resonance frequency [1]. Here we will focus on gradient echoes in more detail, including how they evolve, and the so-called gradient-echo pulse sequences. These include gradient spoiled sequences, RFspoiled sequences and balanced steady-state free precession (SSFP) sequences.