Steady-state sequences: Spoiled and balanced methods
نویسنده
چکیده
In the context of MRI pulse sequences, the term “steady state” typically refers to the equilibrium condition that evolves when magnetization experiences a train of radiofrequency (RF) pulses. If RF pulses occur at broadly spaced intervals (TR≫T1), the magnetization recovers fully between pulses due to relaxation, and the steady-state is identical to the fully-relaxed magnetization, M0. In general, though, RF pulses are applied sufficiently rapidly that the magnetization does not recover fully between pulses (TR<T1), and the magnetization eventually develops a steady-state condition that is distinct from M0. In this manuscript, we assume that both TR and flip angle (α) are constant throughout the pulse sequence.
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