MRI is the imaging technique that has most benefited from technological innovation. The many advances have led to improvements in quality and acquisition speed.
Each sequence is a subtle combination of radiofrequency pulses and gradients. Whatever the type of sequence, the aims are to favor the signal of a particular tissue (contrast), as quickly as possible (speed), while limiting the artifacts and without altering the signal to noise ratio. There are over a hundred different sequences and to complicate things further, manufacturers tend to each choose their own acronyms!
- Spin echo
- Fast spin echo
- Ultrafast spin echo
- Inversion Recovery / STIR / FLAIR
- Gradient echo
- Spoiled gradient echo
- Ultrafast spoiled gradient echo
- Steady-state gradient echo
- T2-enhanced steady-state gradient echo
- Balanced gradient echo
- Echo planar imaging (EPI)
- Hybrid echo (spin echo + gradient echo)