Steady-state free precession imaging

Fully balanced SSFP MRI sequences achieve a phase of zero by refocusing all imaging gradients.

Although the principles underlying echo formation in balanced SSFP have long been known, widespread clinical implementation has been slow due to stringent technical requirements.

bSSFP sequences demand a very high level of magnetic field homogeneity and control over gradient switching and shaping.

During the last decade modern scanners have overcome these limitations making bSSFP a viable and useful sequence on most mid- and high-field systems.

A particular SSFP used for this purpose is one termed TRUE FISP by Siemens, FIESTA by GE, and balanced FFE by Philips.