ULTRAFAST INTERLEAVED GRADIENT-ECHO-PLANAR IMAGING ON A STANDARD SCANNER

Ultra-fast imaging traditionally implies either echo-planar imaging on specially developed gradient systems or very short repetition time gr adient-echo imaging on standard magnetic resonance imaging scanners. A n alternative strategy for very fast imaging with conventional whole-b ody scanners is discussed here. The technique is a hybrid, whereby the advantages of gradient-echo imaging and echo-planar imaging are combi ned. It is here denoted interleaved gradient-echo-planar imaging. It i s not a single specific measurement sequence, but rather a continuum o f 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 seque nce with respect to imaging time, T2 relaxation, gradient power, resol ution, image distortion, and signal-to-noise ratio. In vivo human hear t images, acquired in 110 ms, and with a resolution of 2.5 mm, have be en obtained with a standard whole-body scanner.