Single-Shot ${\text{T}}_{{2}}$ Mapping Through OverLapping-Echo Detachment (OLED) Planar Imaging

Develop a reliable single-shot T2 mapping method with extra robustness to motion and the potential for real-time dynamic and quantitative MR imaging.A single-shot T2 mapping sequence was proposed based on spin-echo planar imaging acquisition scheme. Two overlapped echo signals with different T2 weighting were obtained simultaneously by using two small flip-angle excitation pulses and corresponding echo-shifting gradients. A detachment algorithm based on structure similarity constraint was proposed to separate the two echo signals. T2 mapping was obtained from the two separated echo signals.The robustness and efficiency of the method were demonstrated through simulation, phantom experiments, and human brain measurements.Reliable T2 mapping can be obtained within milliseconds even under continuous head motion.Reliable T2 mapping was achieved with a single shot for the first time. The proposed method will facilitate real-time dynamic and quantitative MR imaging.