Low-power MRI by Frank-sequence excitation.

Recently, a new NMR method employing an rf excitation scheme with strongly reduced power has been introduced, which is based on modulating rf pulses according to Frank sequences. For many applications, a reduction of rf power is essential, e.g. to eliminate bulky rf pre-amplifiers or in medical high-field MRI to preserve patient safety. Another benefit of the new scheme are very short dead times allowing for measurements of samples with short relaxation times. In this work, Frank-sequence excitation is used for low-power imaging for the first time. Results of one-, two-, and three-dimensional imaging experiments are presented and compared to conventional images.