Meeting Banner
Abstract #4260

Ultra-Fast Selective RF Pulse Design for Parallel Transmission Using Pre-Calculated Base Pulses

Ingmar Graesslin1, Annighoefer Bjoern1, Ulrich Katscher1, Peter Brnert2

1Philips Research, Hamburg, Germany; 2Philips Research Laboratory, Hamburg, Germany

Parallel transmission in high-field MRI can improve the B1 homogeneity, as well as speed up multidimensional RF pulses (Transmit SENSE). However, the calculation of such pulses often takes too long for the use in a clinical setting, in particular if RF safety constraints are considered. This work presents a novel simple and efficient approach to calculate selective RF pulses for arbitrary target patterns based on pre-calculated base pulses. The base pulses can be precalculated by using arbitrary RF pulse design algorithms. They can be optimized for SAR or power and are valid for certain k-space trajectories and transmit coil arrangements.

Abstract PDF Presentation Video

Keywords

achieved actual advantageous amount applications arbitrary arrangement arrays black blue body calculating calculation channel channels clear clinical coil coils complex consequently considered constraints consumption convolution curves demonstrating denoting depicted described design desired disc disk efficient eight element elements error even excitation excitations excited exciting experiment extended fairly fast feasibility field fulfilled full function future general generation generic hamburg homogeneity homogeneous improved incorporating increasing independent individual integrating inverse kidney linearly locally long magnetization magnitude mapping maps matrix memory minimize multidimensional multiplication multipliers must named needs normalized notation novel optimized parallel particular particularly pattern patterns peak performance phantom position power preprocessing prior problem prohibited promising proposes pulse pulses rather reduction required requires resolution resolutions respectively restricted safety sampling selective sense setting shaped shimming significantly slice solved space spatial speeding spread step still stored superposition support system systems takes target technical terms thank took trajectories trajectory transmission transmit transverse ultra usage vector versus whole