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Symbol Definition

A Anterior

Angstrom (10-10 meters)

BW Bandwidth

Bo Static magnetic field

B1 The radio frequency magnetic field

B1R Receive B1 magnetic fieldB1T Transmit B1 magnetic field

C Contrast

CW Continuous wave

dB Decibel

DBM Doubly Balanced Mixer

E Energy

EPI Echo Planar Imaging

ESR Electron Spin Resonance

FID Free induction decay

fMRI functional MRI

FT Fourier transformGBP Bipolar magnetic field gradient

Gf Frequency encoding gradient

Gi Field gradient in the i direction

G Phase encoding gradient

Gmax Maximum value of phase encoding gradient.

Gs Slice selection gradient

Gyromagnetic ratio

h Planck's constant

IFT Inverse Fourier transform

IM Imaginary part of a complex numberI Inferior

J Joule

k Boltzmann constant

k kilo (103)

k Proportionality constant

K Kelvin temperature

L Left

LUT Look-up table

m milli (10-3)

micro (10-6)

Mo Equilibrium magnetizationMX X component of magnetization

MX' X' component of magnetization

MY Y component of magnetization

MY' Y' component of magnetization

MZ Z component of magnetization

MXY Transverse component of magnetization

MRA Magnetic resonance angiography

MRI Magnetic resonance imaging

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Resonance frequency in Hertz

N+ Spin population in low energy state

N- Spin population in high energy state

Nex Number of excitations (number of averages)

NMR Nuclear magnetic resonance

Resonance frequency in radians per second

P PosteriorP Power

3.14159...

Phase angle

ppm Parts per million

Q RF coil quality factor

R Right

RE Real part of a complex number

RF Radio frequency

S Superior

s Second

SNR Signal-to-Noise RatioSTS Single-turn solenoid

SAR Specific absorption rate

Sinc Sin(x)/x

T Temperature

T Tesla

T1 Spin-lattice relaxation time

T2 Spin-spin relaxation time

T2* T2 star

T2inhomo Inhomogeneous T2

Rotation angleThk Slice thickness

TE Echo Time

TI Inversion Time

TR Repetition Time

X Axis in laboratory coordinate system

X' Rotating frame X axis

Y Axis in laboratory coordinate system

Y' Rotating frame Y axis

Z Axis in laboratory coordinate system

Acronyms from the MRI Literature

ADC apparent diffusion coefficient

AST arterial spin trapping

BOLD blood oxygenation level-dependent contrast

CE Contrast Enhanced

CSI chemical shift imaging

DRESS depth-resolved surface spectroscopy

DWI diffusion weighted imaging

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EPR electron paramagnetic resonance

EPS echo planar spectroscopy

ESR electron spin resonance

FLAIR fluid-attenuated inversion recovery

HYPR HighlY constrained backPRojection

IDEAL Iterative Decomposition of water and fat with Echo Asymmetry and Least-squares estimation

ISIS Image-selected in vivo spectroscopyk-t k-space and time

k-t-BLAST k-space and time Broad-use Linear Acquisition Speed-up Technique

k-t-SENSE k-space and time Sensitivity Encoding

MR magnetic resonance

MRS magnetic resonance spectroscopy

PC Phase Contrast

PR Projection Reconstruction

PWI perfusion weighted imaging

PRESS point-resolved spectroscopy

RARE rapid acquisition relaxation enhanced

PROPELLER Periodically Rotated Overlapping ParallEL Lines with Enhanced ReconstructionSENSE sensitivity encoding for MRI

SMASH simultaneous acquisition of spatial harmonics

SPACE-RIP sensitivity profiles from an array of coils for encoding and reconstruction in parallel

SPRITE single-point ramped imaging with T1 enhancement

STEAM stimulated echo acquisition mode

STIR short T1 inversion recovery

SI spectroscopic imaging

TRICKS Time-Resolved Imaging of Contrast KineticS

VEST volume excitation using stimulated echoes

VIPR Vastly undersampled isotropic projection imaging