Validation of a Flexible Optimal Control Approach for Rf- Pulse-design including Relaxation Effects and Sar
نویسندگان
چکیده
Radio frequency (RF) pulses are essential in MRI to excite and alter magnetization. We present and validate a flexible approach based on optimal control of the full time-dependent Bloch equation, including relaxation effects. A globally convergent trust-region Newton method with exact derivatives via adjoint calculus allows the efficient computation of optimal pulses. The results are validated on a 3T scanner and demonstrate the ability to generate optimized pulses for arbitrary flip angles and arbitrary slice profiles. Keywords MRI, RF-pulse-design, slice selective excitation, optimal control theory
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تاریخ انتشار 2014