Method and apparatus for reducing an rf power at high-field mr imaging with the use of multi-phase hf-plus stimulus angles

摘要

mr-pulse sequence (100), which is adapted to induced by means of hf power, in order to reduce multi-phase excitation angles, belong to the:a initial contrast preserving phase (110), which has a number of pulses (112), with a large excitation angles, which, however, the initial contrast preserving phase (110); and is largely constanta roll-off phase (120), which has a number of pulses (122) with an excitation angles which is smaller than the excitation angles of the number of pulses (112) in the initial contrast preserving phase (110) and the decreases with time,the pulses of the roll-off phase (120) according to the verse-technology, be formed by the maximum and to reduce the average power.