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Chapter 7
Rapid MR Imaging
Figure 7.13. (a) Axial 256 x 256 spin-echo image of the head; (b) image acquired with the same parameters as in (a) after an intervention was simulated by inserting fluid-filled tubing (indicated by an arrow) into the field of view; (c) keyhole image reconstructed from the reference image in (a) and 64 phase encodings acquired after the intervention. Note that the tubing in the keyhole image is blurred because of insufficient spatial resolution in the phase-encoding direction.