A form of Fourier transformation imaging in which phase encoding gradient pulses are applied for a constant duration but with varying amplitude. The spin warp method, as other Fourier imaging techniques, is relatively tolerant of inhomogeneities in the magnetic fields.

The respiratory phase can be used to control imaging either by only acquiring the image data during a particular portion of the respiratory cycle (which increases image acquisition time) or by adjusting the sequence of image data collection according to the phase of the respiratory cycle in such a way as to minimize motion-induced artifacts in the reconstructed image.

See also Respiratory Ordered Phase Encoding.

The temporal variation of the flip angle (from one RF pulse to the next) to enhance SNR, and/or equalize the signal intensity for each phase encoding step.

The ensemble of raw data points collected during the signal readout. For example, during Cartesian sampling, normally used to refer to data collected with a fixed value of the phase encoding gradient. Also referred to as one line of k-space. In projection reconstruction, the line is radial oriented, while in spiral imaging, it is a spiral.