Optimization of signal behavior in the transition to driven equilibrium in steady‐state free precession sequences

Abstract
A new technique to avoid the initial signal fluctuations in steady‐state free precession (SSFP)‐sequences, such as trueFISP, FIESTA, and refocused FFE, is presented. The “transition into driven equilibrium” (TIDE) sequence uses modified flip angles over the initialization phase of a SSFP experiment, which not only avoids image artifacts but also improves the signal‐to‐noise ratio (SNR) and contrast behavior compared to conventional approaches. TIDE is demonstrated to be robust against variations of T1 and T2, and leads to a monotonous signal evolution for off‐resonance spins. The basic principles can also be applied repetitively to optimize continuous 3D acquisitions. Magn Reson Med 48:801–809, 2002.