|
Code
|
Display
|
Definition
|
|
129102
|
Water/fat out of phase |
Water/Fat Out of phase signal, derived using Dixon or other techniques. |
|
110855
|
Fractional Occupancy Segmentation |
Percentage of the voxel area occupied by the segmented property. |
|
129101
|
Water/fat in phase |
Water/Fat In Phase signal, derived using Dixon or other techniques. |
|
110854
|
Fractional Probabilistic Segmentation |
Probability, defined as a percentage, that the segmented property occupies the spatial area defined by the voxel. |
|
110853
|
Binary Segmentation |
Binary value denoting that the segmented property is present. |
|
129103
|
Water fraction |
The fraction of water present, derived using Dixon or other techniques. |
|
110852
|
MR signal intensity |
Signal intensity of an MR image, not otherwise specified. |
|
110850
|
X-Ray Attenuation |
Decrease in the number of photons in an X-Ray beam due to interactions with the atoms of a material substance. Attenuation is due primarily to two processes, absorption and scattering. |
|
129100
|
Fat fraction |
The fraction of fat present, derived using Dixon or other techniques. |
|
110845
|
YBR ICT CR Component |
CR (Red chrominance) component of a YBR ICT image (Irreversible Color Transform), as defined in JPEG 2000. |
|
110844
|
YBR ICT CB Component |
CB (Blue chrominance) component of a YBR ICT image (Irreversible Color Transform), as defined in JPEG 2000. |
|
110843
|
YBR ICT Y Component |
Y (Luminance) component of a YBR ICT image (Irreversible Color Transform), as defined in JPEG 2000. |
|
110842
|
YBR PARTIAL CR Component |
CR (Red chrominance) component of a YBR PARTIAL image, as defined in JPEG 2000. |
|
110841
|
YBR PARTIAL CB Component |
CB (Blue chrominance) component of a YBR PARTIAL image, as defined in JPEG 2000. |
|
110840
|
YBR PARTIAL Y Component |
Y (Luminance) component of a YBR PARTIAL image, as defined in JPEG 2000. |
|
126061
|
Root Angular Second Moment of GLCM |
The square root of the Angular Second Moment (ASM) of a Gray Level Co-occurrence Matrix (GLCM). A measure of orderliness.See . |
|
110849
|
Echogenicity |
The ability of a material to create an ultrasound return echo. |
|
110848
|
YBR RCT CR Component |
CR (Red chrominance) component of a YBR RCT image (Reversible Color Transform), as defined in JPEG 2000. |
|
110847
|
YBR RCT CB Component |
CB (Blue chrominance) component of a YBR RCT image (Reversible Color Transform), as defined in JPEG 2000. |
|
110846
|
YBR RCT Y Component |
Y (Luminance) component of a YBR RCT image (Reversible Color Transform), as defined in JPEG 2000. |
|
110834
|
RGB R Component |
Red component of a true color image (RGB). |
|
110833
|
Ultrasound Attenuation |
Reduction in strength of ultrasound signal as the wave. |
|
110832
|
Speed of sound |
Speed of sound in tissue. |
|
110831
|
Perfusion |
Scalar value related to the volume of blood perfusing into tissue. |
|
110830
|
Elasticity |
Scalar value related to the elastic properties of the tissue. |
|
110839
|
YBR FULL CR Component |
CR (Red chrominance) component of a YBR FULL image, as defined in JPEG 2000. |
|
126050
|
Fractal Dimension |
A statistical index of complexity comparing how detail in a fractal pattern changes with the scale at which it is measured; a ratio of the change in detail to the change in scale. |
|
110838
|
YBR FULL CB Component |
CB (Blue chrominance) component of a YBR FULL image, as defined in JPEG 2000. |
|
110837
|
YBR FULL Y Component |
Y (Luminance) component of a YBR FULL image, as defined in JPEG 2000. |
|
110836
|
RGB B Component |
Blue component of a true color image (RGB). |
|
110835
|
RGB G Component |
Green component of a true color image (RGB). |
|
113096
|
Creatine+Choline/Citrate Ratio |
For single-proton MR spectroscopy, the ratio between the Choline and Creatine resonance peak and the Citrate resonance peak. |
|
113098
|
Magnetization Transfer Ratio |
Magnetization Transfer Ratio (MTR) is the ratio of magnetization transfer, Mo - Ms/Mo, where Ms represents the magnitude of signal of tissues with the saturation pulse used to saturate macromolecular protons on, and Mo is the magnitude of signal without saturation.See Dousset V, Grossman RI, Ramer KN, Schnall MD, Young LH, Gonzalez-Scarano F, et al. Experimental allergic encephalomyelitis and multiple sclerosis: lesion characterization with magnetization transfer imaging. Radiology. 1992 Feb 1;182(2):483-91. http://dx.doi.org/10.1148/radiology.182.2.1732968 |
|
113094
|
Creatine and Choline |
For single-proton MR spectroscopy, the resonance peak corresponding to creatine and choline. |
|
113095
|
Lipid and Lactate |
For single-proton MR spectroscopy, the resonance peak corresponding to lipid and lactate. |
|
110823
|
Spatial Displacement Y Component |
Spatial Displacement along axis Y of a non linear deformable spatial registration image. The Y axis is defined in reference to the patient's orientation, and is increasing to the posterior side of the patient. |
|
110822
|
Spatial Displacement X Component |
Spatial Displacement along axis X of a non linear deformable spatial registration image. The X axis is defined in reference to the patient's orientation, and is increasing to the left hand side of the patient. |
|
110821
|
Nuclear Medicine Tomographic Activity |
Accumulated decay event counts in a Nuclear Medicine Tomographic image (including PET). |
|
110820
|
Nuclear Medicine Projection Activity |
Accumulated decay event counts in a nuclear medicine projection image. |
|
110829
|
Flow Variance |
Statistical variance of blood velocity relative to mean. |
|
110828
|
Flow Velocity |
Velocity of blood flow based on Doppler measurements. |
|
110827
|
Tissue Velocity |
Velocity of tissue based on Doppler measurements. |
|
110826
|
Indexed Hemodynamic Resistance |
Measured resistance to the flow of blood. |
|
110825
|
Hemodynamic Resistance |
Measured resistance to the flow of blood. |
|
110824
|
Spatial Displacement Z Component |
Spatial Displacement along axis Z of a Non linear deformable spatial registration image. The Z axis is defined in reference to the patient's orientation, and is increasing toward the head of the patient. |
|
112031
|
Attenuation Coefficient |
A quantitative numerical statement of the relative attenuation of the X-Ray beam at a specified point. Coefficient that describes the fraction of a beam of X-Rays or gamma rays that is absorbed or scattered per unit thickness of the absorber. This value basically accounts for the number of atoms in a cubic cm volume of material and the probability of a photon being scattered or absorbed from the nucleus or an electron of one of these atoms. Usually expressed in Hounsfield units [referred to as CT Number in Fraser and Pare]. |
|
126312
|
Ktrans |
Ktrans, the volume transfer constant of a tracer diffusion kinetic model, specifically the volume transfer constant between blood plasma and extravascular extracellular space (EES)See Tofts et al, "Estimating Kinetic Parameters From Dynamic Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10, pp. 223-232, 1999. |
|
126313
|
kep |
kep, the rate constant between extravascular extracellular space (EES) and blood plasmaSee Tofts et al, "Estimating Kinetic Parameters From Dynamic Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10, pp. 223-232, 1999. |
|
126314
|
ve |
ve, the fractional (not absolute) volume of extravascular extracellular space (EES) per unit volume of tissueSee Tofts et al, "Estimating Kinetic Parameters From Dynamic Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10, pp. 223-232, 1999. |
|
126403
|
SUVbsa |
Standardized Uptake Value calculated using body surface area. The patient size correction factor for males and females is weight^ 0.425 * height^0.725 * 0.007184.Defined in Sugawara et al. Reevaluation of the Standardized Uptake Value for FDG: Variations with Body Weight and Methods for Correction.Radiology, 1999 at |
|
126404
|
SUVibw |
Standardized Uptake Value calculated using ideal body weight. The patient size correction factor for males is 48.0 + 1.06 * (height - 152) and for females is 45.5 + 0.91 * (height - 152).Defined in Sugawara et al. Reevaluation of the Standardized Uptake Value for FDG: Variations with Body Weight and Methods for Correction.Radiology, 1999 at |
|
126405
|
SUVlbm(Janma) |
Standardized Uptake Value calculated using lean body mass by Janmahasatian method. The patient size correction factor for males is 9.27E3 * weight / (6.68E3 + 216 * weight / (height^2)) and for females is 9.27E3 * weight / (8.78E3 + 244 * weight / (height^2)).Defined in Janmahasatian et al. Quantification of Lean Bodyweight. Clin Pharmacokinet. 2005 Oct 1;44(10):1051-65. at and its role in SUVlbm(Janma) calculation is discussed in Tahari et al. Optimum Lean Body Formulation for Correction of Standardized Uptake Value in PET Imaging. Journal of Nuclear Medicine. 2014 Sep 1;55(9):1481-4. at . |
|
126406
|
SUVlbm(James128) |
Standardized Uptake Value calculated using lean body mass by James method, using the originally published 128 multiplier for males. The patient size correction factor for males is 1.10 * weight - 128) * (weight/height) ^2, and for females is 1.07 * weight - 148 * (weight/height) ^2. |
|
126400
|
Standardized Uptake Value |
A ratio of locally measured radioactivity concentration versus the injected radioactivity distributed evenly throughout the whole body.This general concept encompasses all specific methods of calculating the whole body volume of distribution, such as using body weight, lean body mass, body surface area, etc. |
|
126401
|
SUVbw |
Standardized Uptake Value calculated using body weight. The patient size correction factor for males and females is body weight.Defined in Sugawara et al. Reevaluation of the Standardized Uptake Value for FDG: Variations with Body Weight and Methods for Correction.Radiology, 1999 at |
|
126402
|
SUVlbm |
Standardized Uptake Value calculated using lean body mass by James method. The patient size correction factor for males is 1.10 * weight - (120 or 128) * (weight/height) ^2, and for females is 1.07 * weight - 148 * (weight/height) ^2.Defined in Sugawara et al. Reevaluation of the Standardized Uptake Value for FDG: Variations with Body Weight and Methods for Correction.Radiology, 1999 at , except that either 120 or 128 may be used as the multiplier parameter for males).Unfortunately, Sugawara used a parameter of 120 rather than 128, propagating an error in Morgan DJ, Bray KM. Lean Body Mass as a Predictor of Drug Dosage: Implications for Drug Therapy. Clinical Pharmacokinetics. 1994;26(4):292-307, which misquoted the original LBM definition that used 128 in James WPT, Waterlow JC. Research on Obesity: A Report of the DHSS/MRC Group. London: Her Majesty’s Stationery Office; 1976. Implementations differ in whether they have used 120 or 128 when using this code. See Kelly M. SUV: Advancing Comparability and Accuracy. Siemens; 2009. Available from: . |
|
113041
|
Apparent Diffusion Coefficient |
Values are derived by calculation of the apparent diffusion coefficient. This concept may be used for the diffusion coefficient of various different models, e.g., mono-exponential (ADCm), kurtosis (ADCk), stretched-exponential (ADCs).The "apparent" appellation is because the diffusion images from which the ADC is computed may also be affected by T2 contrast (T2 "shine-through"), so this concept is distinguished from a "pure" diffusion coefficient that is not so affected. |
|
113043
|
Diffusion weighted |
Values are derived by calculation of the diffusion weighting. |
|
121227
|
Line segment length |
The length of that part of a line (a straight object having no curvature) that is bounded by two distinct end points and contains every point on the line between those two end points, including both of the two end points. |
|
121224
|
Acetabular angle |
The angle on an AP radiograph of the pelvis between a line drawn parallel to the acetabular roof and a line drawn horizontally through the inferior aspect of both triradiate cartilages (Hilgenreiner's line). |
|
113288
|
Volume Ratio |
Coefficient reflecting the anisotropy of the tissues, derived from a diffusion weighted MR image. It represents the volume of an ellipsoid whose semimajor axes are the three eigenvalues of the diffusion tensor divided by the volume of a sphere whose radius is the mean diffusivity. |
|
121222
|
Volume of sphere |
A three-dimensional numeric measurement of a sphere shaped three-dimensional region of interest in an image set. |
|
113289
|
Diffusion Coefficient |
The pure diffusion coefficient, i.e., one that is not affected by T2 contrast effects. |
|
121220
|
Volume of circumscribed sphere |
A three-dimensional numeric measurement of the bounding sphere of a three-dimensional region of interest in an image set. |
|
121221
|
Volume of ellipsoid |
A three-dimensional numeric measurement of an ellipsoid shaped three-dimensional region of interest in an image set. |
|
121217
|
Volume estimated from three or more non-coplanar 2D regions |
A three-dimensional numeric measurement that is approximate, based on three or more non-coplanar two-dimensional image regions. |
|
121218
|
Volume estimated from two non-coplanar 2D regions |
A three-dimensional numeric measurement that is approximate, based on two non-coplanar two-dimensional image regions. |
|
121216
|
Volume estimated from single 2D region |
A three-dimensional numeric measurement that is approximate, based on a two-dimensional region in a single image. |
|
121211
|
Path length |
A one dimensional, or linear, numeric measurement along a polyline. |
|
121219
|
Volume of bounding three dimensional region |
A three-dimensional numeric measurement of the bounding region of a three-dimensional region of interest in an image set. |
|
126220
|
R2-Coefficient |
Coefficient of determination, R2. An indication of goodness of fit. |
|
126221
|
Chi-square |
Pearson's Χ2 test. |
|
126222
|
D-W |
Durbin-Watson statistic for detecting serial correlation in residuals.See . |
|
126223
|
AIC |
Akaike information criterion. A measure of the balance between goodness of fit and number of free parameters.See Akaike H. A new look at the statistical model identification. IEEE Transactions on Automatic Control. 1974 Dec;19(6):716-23. . |
|
126224
|
BIC |
Bayesian information criterion. A measure of the balance between goodness of fit and model complexity.See . |
|
121206
|
Distance |
A one dimensional, or linear, numeric measurement. |
|
121207
|
Height |
Vertical measurement value. |
|
130086
|
Relative Linear Stopping Power |
Ratio of the linear stopping power of a material to the linear stopping power of water. |
|
126330
|
tau_m |
τm. The mean intracellular water lifetime (τi). Used in the Shutter-Speed Model (SSM) of tracer kinetics. |
|
126331
|
vp |
vp. The fractional (not absolute) blood plasma volume per unit volume of tissue.See Tofts et al, "Estimating Kinetic Parameters From Dynamic Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10, pp. 223-232, 1999. |
|
128512
|
Equivalent Dose |
Absorbed dose to a tissue or organ multiplied by a quality factor to normalize the dose to the type of radiation that is depositing the dose. |
|
130403
|
Gradient-weighted class activation |
Values are derived using the gradients of a target class flowing into the final convolutional layer of a convolutional neural network to produce a localization map highlighting the important regions in the image for predicting a class. The gradient-weighted class activation map (Grad-CAM) indicates the discriminative image regions used by the network to identify a class. |
|
130402
|
Class activation |
Values are derived using global average pooling in convolutional neural networks to produce a localization map highlighting the important regions in the image for predicting a class. The class activation map (CAM) indicates the discriminative image regions used by the network to identify a class. |
|
128513
|
Absorbed Dose |
Energy from ionizing radiation absorbed per unit mass. |
|
130404
|
Saliency |
Values are derived using a single back-propagation pass through a network to produce a localization map highlighting the spatial support of a given class in a given image. |
|
126326
|
IAUC90BN |
The initial area under the contrast agent concentration-time curve at 90 seconds after the onset time, normalized with the corresponding arterial input function, such that IAUC90BN = IAUC90 / IAUC90AIF. |
|
126327
|
IAUC180BN |
The initial area under the contrast agent concentration-time curve at 180 seconds after the onset time, normalized with the corresponding arterial input function, such that IAUC180BN = IAUC180 / IAUC180AIF. |
|
126320
|
IAUC |
The initial area under the contrast agent concentration-time curve |
|
126321
|
IAUC60 |
The initial area under the contrast agent concentration-time curve at 60 seconds after the onset time |
|
126322
|
IAUC90 |
The initial area under the contrast agent concentration-time curve at 90 seconds after the onset time |
|
126323
|
IAUC180 |
The initial area under the contrast agent concentration-time curve at 180 seconds after the onset time |
|
126324
|
IAUCBN |
The initial area under the contrast agent concentration-time curve, normalized with the corresponding arterial input function, such that IAUCBN = IAUC / IAUCAIF. |
|
126325
|
IAUC60BN |
The initial area under the contrast agent concentration-time curve at 60 seconds after the onset time, normalized with the corresponding arterial input function, such that IAUC60BN = IAUC60 / IAUC60AIF. |
|
113080
|
Glutamate and glutamine |
For single-proton MR spectroscopy, the resonance peak corresponding to glutamate and glutamine. |
|
113081
|
Choline/Creatine Ratio |
For single-proton MR spectroscopy, the ratio between the Choline and Creatine resonance peaks. |
|
113082
|
N-acetylaspartate/Creatine Ratio |
For single-proton MR spectroscopy, the ratio between the N-acetylaspartate and Creatine resonance peaks. |
|
113083
|
N-acetylaspartate/Choline Ratio |
For single-proton MR spectroscopy, the ratio between the N-acetylaspartate and Choline resonance peaks. |
|
113084
|
Tmax |
The time delay to the maximum of the residue function after deconvolution.Shih LC, Saver JL, Alger JR, Starkman S, Leary MC, Vinuela F, et al. Perfusion-Weighted Magnetic Resonance Imaging Thresholds Identifying Core, Irreversibly Infarcted Tissue. Stroke. 2003 Jun 1;34(6):1425-30. doi:10.1161/01.STR.0000072998.70087.E9. Østergaard L, Weisskoff RM, Chesler DA, Gyldensted C, Rosen BR. High resolution measurement of cerebral blood flow using intravascular tracer bolus passages. Part I: Mathematical approach and statistical analysis. Magnetic Resonance in Medicine. 1996;36(5):715-25. doi:10.1002/mrm.1910360510. |
|
126395
|
R2* |
The transverse relaxation rate constant for the decay of transverse magnetization caused by a combination of spin-spin relaxation and magnetic field inhomogeneity. The inverse of transverse relaxation time, i.e., R2* = 1/T2*. |
|
110812
|
Volumetric Diffusion Dxz Component |
Dxz Component of the diffusion tensor, quantifying the correlation of molecular displacements in the X and Z directions. |
|
126396
|
Magnetic Susceptibility |
Magnetic Susceptibility is a measure of the amount of magnetization induced in a material when placed in an external magnetic field. It is the quantity encoded as the voxel intensity in Quantitative Susceptibility Map (QSM) images.It is a dimensionless quantity, usually recorded with units of parts per millions (ppm).See Liu T, Wisnieff C, Lou M, Chen W, Spincemaille P, Wang Y. Nonlinear formulation of the magnetic field to source relationship for robust quantitative susceptibility mapping. Magnetic Resonance in Medicine. 2013;69(2):467-76. .See Wang Y, Liu T. Quantitative susceptibility mapping (QSM): Decoding MRI data for a tissue magnetic biomarker. Magnetic Resonance in Medicine. 2015;73(1):82-101. . |
|
110811
|
Volumetric Diffusion Dxy Component |
Dxy Component of the diffusion tensor, quantifying the correlation of molecular displacements in the X and Y directions. |
|
110810
|
Volumetric Diffusion Dxx Component |
Dxx Component of the diffusion tensor, quantifying the molecular mobility along the X axis. |
|
126397
|
Relative Regional Blood Flow |
The relative flow rate of blood perfusing a region. Obtained by dividing the absolute flow rate of blood perfusing a region by the absolute flow rate of blood perfusing a reference region. |
|
126398
|
Relative Regional Blood Volume |
The relative volume of blood perfusing a region. Obtained by dividing the absolute volume of blood perfusing a region by the absolute volume of blood perfusing a reference region. |
|
110819
|
Blood Oxygenation Level |
Signal intensity of a Blood Oxygenation Level image. Used in Photoacoustic Imaging and functional MR. In functional MR BOLD imaging it is used for detecting brain activation and is sensitive to blood oxygenation (but also to cerebral blood flow and volume). |
|
110818
|
T2* Weighted Dynamic Contrast Enhanced MR Signal Intensity |
Signal intensity of a T2* Weighted Dynamic Contrast Enhanced MR image. A T2* Weighted Dynamic Contrast Enhanced MR image reflects the T2* of tissue decrease as the Gd contrast agent bolus passes through the brain. |
|
110817
|
T2 Weighted Dynamic Contrast Enhanced MR Signal Intensity |
Signal intensity of a T2 Weighted Dynamic Contrast Enhanced MR image. A T2 Weighted Dynamic Contrast Enhanced MR image reflects the T2 of tissue decrease as the Gd contrast agent bolus passes through the brain. |
|
126390
|
Absolute Regional Blood Flow |
The absolute flow rate of blood perfusing a region as volume per mass per unit of time. The mass divisor may be approximated by a measurement of volume assuming a tissue density of 1. |
|
110816
|
T1 Weighted Dynamic Contrast Enhanced MR Signal Intensity |
Signal intensity of a T1 Weighted Dynamic Contrast Enhanced MR image. A T1 Weighted Dynamic Contrast Enhanced MR image reflects the dynamics of diffusion of the exogenous contrast media from the blood pool into the extra vascular extracellular space (EES) of the brain at a rate determined by the blood flow to the tissue, the permeability of the Brain Blood Barrier (BBB), and the surface area of the perfusing vessels. |
|
126391
|
Absolute Regional Blood Volume |
The absolute volume of blood perfusing a region as volume per mass. The mass divisor may be approximated by a measurement of volume assuming a tissue density of 1. |
|
110815
|
Volumetric Diffusion Dzz Component |
Dzz Component of the diffusion tensor, quantifying the molecular mobility along the Z axis. |
|
126392
|
Oxygen Extraction Fraction |
The percent of the oxygen removed from the blood by tissue during its passage through the capillary network. For example, as measured by blood oxygenation level dependent (BOLD) MR. See He, Xiang, and Dmitriy A. Yablonskiy. "Quantitative BOLD: Mapping of Human Cerebral Deoxygenated Blood Volume and Oxygen Extraction Fraction: Default State." Magnetic Resonance in Medicine 57, no. 1 (2007): 115-26. |
|
126393
|
R1 |
The longitiudinal relaxation rate constant for the decay of longitiudinal magnetization caused by spin-lattice relaxation. The inverse of longitudinal relaxation time, i.e., R1 = 1/T1. |
|
110814
|
Volumetric Diffusion Dyz Component |
Dyz Component of the diffusion tensor, quantifying the correlation of molecular displacements in the Y and Z directions. |
|
126394
|
R2 |
The transverse relaxation rate constant for the decay of transverse magnetization caused by spin-spin relaxation. The inverse of transverse relaxation time, i.e., R2 = 1/T2. |
|
110813
|
Volumetric Diffusion Dyy Component |
Dyy Component of the diffusion tensor, quantifying the molecular mobility along the Y axis. |
|
113070
|
Velocity encoded |
Values are derived by calculating values based on velocity encoded. |
|
113071
|
Z-score |
Values are derived by calculating the value of the Z-Score statistic from multiple image samples. |
|
110801
|
Contrast Agent Angio MR Signal Intensity |
Signal intensity of a Contrast Agent Angio MR image. |
|
110800
|
Spin Tagging Perfusion MR Signal Intensity |
Signal intensity of a Spin tagging Perfusion MR image. Spin tagging is a technique for the measurement of blood perfusion, based on magnetically labeled arterial blood water as an endogenous tracer. |
|
110809
|
Relative Anisotropy |
Coefficient reflecting the relative anisotropy of the tissues, derived from a diffusion weighted MR image. |
|
110808
|
Fractional Anisotropy |
Coefficient reflecting the fractional anisotropy of the tissues, derived from a diffusion weighted MR image. Fractional anisotropy is proportional to the square root of the variance of the Eigen values divided by the square root of the sum of the squares of the Eigen values. |
|
110807
|
Field Map MR Signal Intensity |
Signal intensity of a Field Map MR image. A Field Map MR image provides a direct measure of the B0 inhomogeneity at each point in the image. |
|
110806
|
T2* Weighted MR Signal Intensity |
Signal intensity of a T2* Weighted MR image. The T2* phenomenon results from molecular interactions (spin spin relaxation) and local magnetic field non-uniformities, which cause the protons to precess at slightly different frequencies. |
|
110805
|
T2 Weighted MR Signal Intensity |
Signal intensity of a T2 Weighted MR image. T2 Weighted image contrast state is approached by imaging with a TR long compared to tissue T1 (to reduce T1 contribution to image contrast) and a TE between the longest and shortest tissue T2s of interest. |
|
110804
|
T1 Weighted MR Signal Intensity |
Signal intensity of T1 Weighted MR image. A T1 Weighted MR image is created typically by using short TE and TR times. |
|
110803
|
Proton Density Weighted MR Signal Intensity |
Signal intensity of a Proton Density Weighted MR image. All MR images have intensity proportional to proton density. Images with very little T1 or T2 weighting are called 'PD-weighted'. |
|
110802
|
Time Of Flight Angio MR Signal Intensity |
Signal intensity of a Time-of-flight (TOF) MR image. Time-of-flight (TOF) is based on the phenomenon of flow-related enhancement of spins entering into an imaging slice. As a result of being unsaturated, these spins give more signal that surrounding stationary spins. |
|
113063
|
T1 |
The time constant for the decay of longitiudinal magnetization caused by spin-lattice relaxation. The inverse of the longitudinal relaxation rate constant, i.e., T1 = 1/R1. |
|
113064
|
T2* |
The time constant for the decay of transverse magnetization caused by a combination of spin-spin relaxation and magnetic field inhomogeneity. The inverse of the transverse relaxation rate constant, i.e., T2* = 1/R2*. |
|
113065
|
T2 |
The time constant for the decay of transverse magnetization caused by spin-spin relaxation. The inverse of the transverse relaxation rate constant, i.e., T2 = 1/R2. |
|
113066
|
Time course of signal |
The time course of signal. |
|
113067
|
Temperature encoded |
Values are derived by calculating values based on temperature encoding. |
|
113068
|
Student's T-test |
Values are derived by calculating the value of the Student's T-Test statistic from multiple image samples. |
|
113069
|
Time To Peak |
The time from the start of the contrast agent injection to the maximum enhancement value. |
|
113060
|
Signal to noise |
The ratio of the desired signal to the level of noise. |
|
126374
|
Temporal Derivative Threshold |
A threshold applied to the temporal derivative of the concentration-time curve. |
|
126375
|
Maximum Slope |
The maximum rate of signal intensity change within a measured region of a time-activity curve. See Boonsirikamchai, Piyaporn, Harmeet Kaur, Deborah A. Kuban, Edward Jackson, Ping Hou, and Haesun Choi. "Use of Maximum Slope Images Generated From Dynamic Contrast-Enhanced MRI to Detect Locally Recurrent Prostate Carcinoma After Prostatectomy: A Practical Approach." American Journal of Roentgenology 198, no. 3 (March 1, 2012): W228-W236. doi:10.2214/AJR.10.6387. |
|
126376
|
Maximum Difference |
The maximum degree of signal intensity change within a measured region of a time-activity curve. See Boonsirikamchai, Piyaporn, Harmeet Kaur, Deborah A. Kuban, Edward Jackson, Ping Hou, and Haesun Choi. "Use of Maximum Slope Images Generated From Dynamic Contrast-Enhanced MRI to Detect Locally Recurrent Prostate Carcinoma After Prostatectomy: A Practical Approach." American Journal of Roentgenology 198, no. 3 (March 1, 2012): W228-W236. doi:10.2214/AJR.10.6387. |
|
126377
|
Tracer Concentration |
Tracer concentration in tissue. |
|
126370
|
Time of Peak Concentration |
The time at which the concentration-time curve achieves its peak for the first time. Used as a concept name for a value or as a method. |
|
126371
|
Bolus Arrival Time |
The nominal time at which arrival of a contrast bolus is detected, which is used as a reference point for subsequent calculations. Used as a concept name for a value or as a method. No specific computational method is implied by this general definition. Abbreviated BAT. |
|
126372
|
Time of Leading Half-Peak Concentration |
The time at which the concentration-time curve achieves half of its peak density for the first time. Used as a concept name for a value or as a method. |
|
113052
|
Mean Transit Time |
The time required for blood to pass through a region of tissue. |
|
113294
|
Kurtosis Diffusion Coefficient |
The diffusion coefficient of a kurtosis diffusion model (ADCk). |
|
113295
|
Gamma Distribution Scale Parameter |
The scale (theta) parameter of a gamma distribution diffusion model. |
|
113054
|
Negative enhancement integral |
The area described by the baseline and the signal loss due to passage of contrast bolus in tissue in a perfusion experiment. Abbreviated NEI or N1. |
|
113296
|
Gamma Distribution Shape Parameter |
The shape (k) parameter of a gamma distribution diffusion model. |
|
113297
|
Gamma Distribution Mode |
The mode (maximum value of probability density function) of a gamma distribution diffusion model. Computed as (k-1)*theta, for k >= 1. |
|
113298
|
Distributed Diffusion Coefficient |
The distributed diffusion coefficient of a stretched-exponential diffusion model (ADCs). |
|
113057
|
R-Coefficient |
Correlation Coefficient, r. |
|
113299
|
Anomalous Exponent Parameter |
The anomalous exponent (stretching, alpha) parameter of a stretched-exponential diffusion model. This describes the deviation of the signal attenuation from mono-exponential behavior |
|
113058
|
Proton Density |
Values are derived by calculating proton density values. |
|
113059
|
Signal change |
The relative change in signal. |
|
113290
|
Mono-exponential Apparent Diffusion Coefficient |
The diffusion coefficient of a mono-exponential diffusion model (ADCm). |
|
113291
|
Slow Diffusion Coefficient |
The slow diffusion coefficient (Ds) of a bi-exponential intravoxel incoherent motion (IVIM) diffusion model. |
|
113292
|
Fast Diffusion Coefficient |
The fast diffusion coefficient (Df) of a bi-exponential intravoxel incoherent motion (IVIM) diffusion model. |
|
113293
|
Fast Diffusion Coefficient Fraction |
The fast diffusion fraction of a bi-exponential intravoxel incoherent motion (IVIM) diffusion model. |