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Flashcards in MRI 4 Deck (6)
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1

Slice selection

The combined use of a spatial magnetic field gradient and an electromagnetic pulse to excite spins within a slice.

2

Spatial gradient (G)

A magnetic field whose strength varies systematically over space.

3

Frequency encoding gradient (Gx)

A gradient that is applied during the data acquisition period, so that the spin precession frequencies change over space.

4

Phase encoding gradient (Gy)

A gradient that is applied before the data acquisition period, so that spins accumulate differential phase offsets over space.

5

k-space

A notation scheme used to describe MRI data acquisition. The use of k-space provides a mathematical and conceptual advantages for describing the acquired MR signal in image form.

6

Fourier transform (FT)

A mathematical technique for converting a signal (i.e. changes of intensity over time) into the frequencies that make it up.