Rotating-frame imaging

The basic timing sequence for rotating-frame imaging with 2D spatial resolution in y-and z-directions is illustrated in Fig. 6.3.2 [Houl]. In z-direction the gradient is applied in the LCF. In y-direction it is applied in the RCF. The components of the magnetic field... 

The image is obtained directly by 2D Fourier transformation over /j and t2, whereby a phase twist can be avoided as a consequence of amplitude modulation. For 1D rotating-frame imaging the field-gradient rf pulse of variable length tj is broken down into a series of short pulses for acquisition of one data point within each delay between the... 

Fig. 6.3.3 [Hou2] Vector diagrams of magnetization illustrating the principle of phase modulation in rotating-frame imaging for a selected volume element. Following an initial y pulse of length ti with variable flip angle 6, the magnetization is placed into the xz plane (left).

In combination with multi-pulse excitation, rotating-frame imaging can also be used for imaging of solids [Choi]. A time-suspension multi-pulse sequence (cf. Table 3.1) is applied to the sample by use of an rf coil with a homogeneous B field so that both... 

MAGROFI mangnetization-grating rotating-frame imaging MEK methylethyl ketone (2-butanone)... 

There has been little development in the theory of MEM in recent years, however the diversity of applications has increased greatly. Examples include the measurement of rotameric distribution in carbohydrates, peptides,or more generally - in isotropic environments. Other applications include studies of the internal order in liquid crystals, a new attempt at the in vivo application of phase-modulated rotating-frame imaging (PMRFI),- - and a study of amphiphilic molecules in ternary systems. 

MAGROR Magnetization Grid Rotating-Frame Imaging... 

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