Parallel Excitation of Nuclear Spins With Local SAR Control

摘要: A method of exciting nuclear spins in a sample, wherein plurality transmit coils are driven parallel to emit respective radio-frequency excitation pulses, the comprising computing phases and/or amplitudes said pulses by solving an optimization problem for minimizing difference between distribution within sample and target distribution, being characterized that: includes cost function depending on power emitted through coil-dependent weighting coefficients; that computed iteratively, each iteration step comprising: based present values coefficient, subsequently updating value at least one coefficients so as control predetermined way local specific absorption rate—SAR—distribution sample. The invention allows, particular, reducing SAR maximum ensuring takes its region