Christoffer Laustsen1, 2, Sean Bowen3, Mads Sloth Vinding4, Niels Christian Nielsen4, Jan Henrik Ardenkjaer-larsen3, 5
1The MR Research Centre, Aarhus University, Aarhus, Denmark; 2Danish Research Centre for Magnetic Resonance,, Hvidovre Hospital, Hvidovre, Denmark; 3Department of Electrical Engineering,, Technical University of Denmark, Lyngby, Denmark; 4Center for Insoluble Protein Structures (inSPIN), Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhs, Denmark; 5GE healthcare, Broendby, Denmark
Hyperpolarized compounds has so far been limited by the T1 decay of the magnetization. Recently the novel method magnetization-to-singlet order (M2S) and singlet order-to-magnetization (S2M), has been shown applicable on pre-clinical MRI systems, extending the hyperpolarized life time several orders of magnitude. However, several limitations are imposed by clinical MRI systems with typical hardware constraints such as low maximum B1 amplitude and lower static magnetic field B0. The large B1 and B0 inhomogenties combined with T2 relaxation impose severe limitations on the efficiency of the method. Here we show a possible solution via optimal control theory, finding pulses with maximum efficiency even under clinical conditions.