Echo-planar imaging

Fig. 1.21 Echo Planar Imaging (EPI) pulse sequence. Gradient-echo based multiple echoes are used for fast single-shot 2D imaging. Slice selection along Gs and frequency encoding along C, are utilized. Phase encoding is realized using short blipped gradient pulses along Gp.

Three general ultra-fast sampling strategies are used Echo planar imaging... 

B.J. Dardzinski, C.H. Sotak, Rapid tissue oxygen tension mapping using F inversion-recovery echo-planar imaging of Perfluoro-15-crown-5-ether, Magn. Reson. Med. 32 (1994) 88-97. 

Three sampling strategies are now introduced echo planar imaging (EPI), rapid acquisition with relaxation enhancement (RARE), and low excitation angle imaging. The first two are based on the sampling of more than one line of k-space for each r.f. excitation, and the third uses rapid multiple r.f. excitations. 

Stehling, M.K., R. Turner, and P. Mansfield "Echo-Planar Imaging in a Fraction of a Second, Science, 43 (October 4, 1991). 

Figure 16.18. Pulse sequence of echo planar imaging.

E/A, emission-absorption CIDNP net effect EPI, echo planar imaging EPR, electron paramagnetic resonance ESR, electron spin resonance (same as EPR) exp, exponentiation on the base e... 

FIGURE 14.3 Pulse sequence for echo-planar imaging. Slice selection is carried out as in Fig. 14.2. The readout gradient Gy is rapidly switched in direction in synchrony with application of a pulsed phase-encode gradient G as indicated. Data are acquired while Gy is turned on but Gx is off. 

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