Categories
Abbreviations

EPI

Echo Planar Imaging

In Brief

Rapid changes of frequency-encoding gradient polarity to refocus the MR echo many times after a single RF excitation, with a small change in phase encoding for each echo to read out different lines of k-space.

EPI is one of the fastest methods of acquiring MRI k-space data. If all data for an image is acquired after one RF excitation, it is single-shot EPI, in which each slice is acquired in one TR.

“The breakthrough came in 1977 with the introduction of echo-planar imaging (EPI). This snap-shot technique meant that in principle complete two-dimensional images could be achieved in extremely short times ranging from 20–50 ms. However, to achieve these acquisition times, yet another inventive step was required. This was the introduction of active magnetic screening.”

Sir Peter Mansfield, Nobel lecture, 2003

Vendor Implementations

All vendors.

Categories
Abbreviations Sequences

FSE

Fast Spin Echo. See RARE

Categories
Abbreviations Sequences

TSE

Turbo Spin Echo. See RARE

Categories
Abbreviations Sequences

RARE

Rapid Acquisition with Relaxation Enhancement

In Brief

RARE is also known on MR systems as TSE, or FSE.

More Detail

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Vendor implementations

Philips: Turbo Spin Echo
Siemens: Turbo Spin Echo
GE: Fast Spin Echo

Categories
Abbreviations

STIR

Short TI Inversion Recovery

In Brief

A fat suppression method suitable for large fields-of-view, or regions of higher magnetic susceptibility variation.

Categories
Abbreviations Sequences

DWI

Diffusion Weighted Imaging

In Brief

In DWI contrast is created based on how far water molecules can randomly disperse due to Brownian motion. This tells us about the structure of tissues at the cellular level.

Categories
Abbreviations Sequences

DWIBS

Diffusion Weighted whole body Imaging with body Background signal Suppression.

In Brief

Multi-station whole-body DWI with STIR fat suppression.

Categories
Abbreviations Sequences

SPLICE

Split acquisition of fast spin echo signals for diffusion imaging.

In Brief

Acquisition of both a spin echo and a stimulated echo, to allow faster and higher resolution diffusion-weighted imaging (DWI) than single-shot TSE diffusion, as well as lower distortion than EPI-based diffusion imaging.