Titlebook: Clinical MR Imaging and Physics; A Tutorial Haris S. Chrysikopoulos Book 2009 Springer-Verlag Berlin Heidelberg 2009 MR Angiography.MR Phys

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Excitation Phenomena,ation), under the influence of the static field B. However, the magnetization vector M cannot be measured directly; thus, in order to investigate the patient we need to disturb the steady state and to observe the course of M as it returns to equilibrium.

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T1 Relaxation (Longitudinal or Spin-Lattice Relaxation),nment (lattice). The 90° pulses (β) keep the entire bulk magnetization M on the xy plane, i.e., M. = 0. When the β pulse is withdrawn, the magnetization vector M begins its course toward equilibrium with gradual growth along the z-axis toward the value M. (Fig. 9).

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Free Induction Decay,(see Chap. 5). Since M. rotates in the xy plane, it is an oscillating magnetic field, and as such it induces the flow of electric current in a coil. Thus, through a coil or antenna the MR signal is transformed into an electric signal that describes a sinusoidal time course with rapid damping (Fig. 19).

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Book 2009 the MRI procedure. Te patient properties called spin, and can interact with electro- is placed in a magnetic feld and becomes temporarily 1 magnetic (EM) radiation through a process called magnetized. Resonance is achieved through the - resonance. When such nuclei absorb EM energy they plication of