Ultrafast interleaved gradient‐echo‐planar imaging on a standard scanner

Abstract

Ultra-fast imaging traditionally implies either echo-planar imaging on specially developed gradient systems, or very short repetition time gradient-echo imaging on standard magnetic resonance imaging scanners. An alternative strategy for very fast imaging with conventional whole-body scanners is discussed here. The technique is a hybrid, whereby the advantages of gradient-echo imaging and echo-planar imaging are combined. It is here denoted interleaved gradient-echo-planar imaging. It is not a single specific measurement sequence, but rather a continuum of sequences whereby multiple excitations with multiple gradient-echos are employed. The power of this fast imaging approach is that one has much more flexibility toward the optimization of the measurement sequence with respect to imaging time, T₂ relaxation, gradient power, resolution, image distortion, and signal-to-noise ratio. In vlvo human heart images, acquired in 110 ms, and with a resolution of 2.5 mm, have been obtained with a standard whole-body scanner.