RF Concatenation with Spiral In-and-Out Trajectory for Two-Dimensional Large-Tip-Angle Excitation
نویسندگان
چکیده
Introduction: A time-reversed concatenated RF pulse can be regarded as a composite pulse in which the error in the first half of the pulse is corrected by the second. The method is general in that it is not restricted to a particular tip angle, and is effective since the tip angle of the first pulse is doubled by the second [1]. A major drawback of the method applied in one-dimensional selective inversion is its sensitivity to off-resonance effect. Here we show that the method can be extended to multi-dimensional excitation with multiple coils, and that off-resonance sensitivity is much reduced in two-dimensional excitation with a spiral in-and-out trajectory where the peaks in the two subpulses can be placed close to each other.
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