1 Letter Ballot STATUS 2 2014/09/08 Date of Last Update 3 David Clunie 4 mailto:[email protected]Person Assigned 5 Andriy Fedorov 6 mailto:[email protected]Submitter Name 7 2014/03/03 Submission Date 8 Correction Number CP-1391 9 Log Summary: Addition of Quantity Descriptors for Perfusion and Tracer Kinetic Modelling 10 Name of Standard 11 PS3.16 2014b 12 Rationale for Correction: 13 The "Abstract Multi-dimensional Image Model Component Semantics" and related units context groups have very limited support 14 for perfusion and tracer kinetic modelling concepts, whether it is performed by CT, PET or MR. Further, many concepts lack meaningful 15 definitions (i.e., are circular). 16 Add definitions where relevant and add new concepts specifically to support CT perfusion, and Dynamic Contrast Enhanced (DCE) 17 MRI, whether it be performed using relaxivity (T1) or susceptibility (T2*) methods. 18 Concepts are added that reflect common usage in specific body parts (e.g., regional "cerebral" blood flow) as well as more general 19 terms that reflect spread of the technique to other body parts (e.g., "regional blood flow" for use in breast, etc.). 20 Tracer kinetic (pharmaco-kinetic) model parameter concepts (like Ktrans) are described generally, without specifying their measurement 21 method or modality, allowing their re-use (e.g., for MR or PET) (and post-coordination by the appropriate technique concepts). 22 These concepts are useful both for encoding of measurements of ROIs in SRs as well as RWVMs in images or as separate objects 23 that describe images. 24 Resolve duplicates for "Attenuation Coefficient" (112031 and 110851). 25 Editor's Notes: 26 Correction Wording: 27 - Letter Ballot - 28 Page 1 CP-1391 - Addition of Quantity Descriptors for Perfusion and Tracer Kinetic Modelling
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1 Letter BallotSTATUS2 2014/09/08Date of Last Update3 David Clunie
8 Correction Number CP-13919 Log Summary: Addition of Quantity Descriptors for Perfusion and Tracer Kinetic Modelling10 Name of Standard
11 PS3.16 2014b12 Rationale for Correction:
13 The "Abstract Multi-dimensional Image Model Component Semantics" and related units context groups have very limited support14 for perfusion and tracer kinetic modelling concepts, whether it is performed by CT, PET or MR. Further, many concepts lack meaningful15 definitions (i.e., are circular).
16 Add definitions where relevant and add new concepts specifically to support CT perfusion, and Dynamic Contrast Enhanced (DCE)17 MRI, whether it be performed using relaxivity (T1) or susceptibility (T2*) methods.
18 Concepts are added that reflect common usage in specific body parts (e.g., regional "cerebral" blood flow) as well as more general19 terms that reflect spread of the technique to other body parts (e.g., "regional blood flow" for use in breast, etc.).
20 Tracer kinetic (pharmaco-kinetic) model parameter concepts (like Ktrans) are described generally, without specifying their measurement21 method or modality, allowing their re-use (e.g., for MR or PET) (and post-coordination by the appropriate technique concepts).
22 These concepts are useful both for encoding of measurements of ROIs in SRs as well as RWVMs in images or as separate objects23 that describe images.
24 Resolve duplicates for "Attenuation Coefficient" (112031 and 110851).25 Editor's Notes:26 Correction Wording:
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28 Page 1CP-1391 - Addition of Quantity Descriptors for Perfusion and Tracer Kinetic Modelling
9 The anatomic location relevant to the application of any AIF method is not pre-coordinated in concepts in this Context Group.10 Typically these would be described by the Finding Site of any related measurements in the appropriate template.
11 CID cc2c2e Bolus Arrival Time Derivation Methods
12 Type:13 Extensible
14 Version:15 yyyymmdd
16 Table CID cc2c2e. Bolus Arrival Time Derivation Methods
17 Code MeaningCode ValueCoding Scheme Designator18 Temporal Derivative Exceeds Thresholddd3d23DCM19 Time of Peak Concentrationdd3d20DCM20 Time of Leading Half-Peak Concentrationdd3d22DCM
21 Note
22 CID cc2c2f Perfusion Analysis Methods
23 Type:24 Extensible
25 Version:26 yyyymmdd
27 Table CID cc2c2f. Perfusion Analysis Methods
28 Code MeaningCode ValueCoding Scheme Designator29 Least Mean Square (LMS) deconvolutiondd2d51DCM30 Singular Value Decomposition (SVD) deconvolutiondd2d52DCM
31 Note
32 CID cc2c2 Quantitative Methods used for Perfusion And Tracer Kinetic Models
33 Type:34 Extensible
35 Version:36 yyyymmdd
37 Table CID cc2c2. Quantitative Methods used for Perfusion And Tracer Kinetic Models
38 Code MeaningCode ValueCoding Scheme Designator39 Include CID cc2c2a “T1 Measurement Methods”40 Include CID cc2c2b “Tracer Kinetic Models”41 Include CID cc2c2c “Perfusion Measurement Methods”
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1 Code MeaningCode ValueCoding Scheme Designator2 Include CID cc2c2d “Arterial Input Function Measurement Methods”3 Include CID cc2c2e “Bolus Arrival Time Derivation Methods”4 Include CID cc2c2f “Perfusion Analysis Methods”5 Model-free concentration-time quantitificationdd2d73DCM
6 Note
7 1. Concepts from this context group may be used in measurement templates to describe the measurement method of8 measurement on an ROI.
4 Code MeaningCode ValueCoding Scheme Designator5 IAUCdd2d63DCM6 IAUC60dd2d64DCM7 IAUC90dd2d65DCM8 Time of Peak Concentrationdd3d20DCM9 Time of Leading Half-Peak Concentrationdd3d22DCM10 Bolus Arrival Timedd3d21DCM11 Time To Peak113069DCM12 Temporal Derivative Thresholddd3d24DCM13 Maximum Slopedd3d25DCM14 Maximum Differencedd3d26DCM15 Tracer Concentrationdd3d27DCM
28 Least Mean Square (LMS) deconvolutionLeast Mean Square (LMS)29 deconvolution
dd2d51
30 Singular Value Decomposition (SVD) deconvolutionSingular Value31 Decomposition (SVD)32 deconvolution
dd2d52
33 K34 trans, the volume transfer constant of a tracer diffusion kinetic model,35 specifically the volume transfer constant between blood plasma and36 extravascular extracellular space (EES)
37 See Tofts et al, "Estimating Kinetic Parameters From Dynamic38 Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized39 Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10,40 pp. 223–232, 1999.
Ktransdd2d60
41 k42 ep, the rate constant between extravascular extracellular space (EES) and43 blood plasma
44 See Tofts et al, "Estimating Kinetic Parameters From Dynamic45 Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized46 Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10,47 pp. 223–232, 1999.
kepdd2d61
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1 NotesDefinitionCode MeaningCode Value2 v3 e, the fractional (not absolute) volume of extravascular extracellular space4 (EES) per unit volume of tissue
5 See Tofts et al, "Estimating Kinetic Parameters From Dynamic6 Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized7 Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10,8 pp. 223–232, 1999.
vedd2d62
9 The intial area under the contrast agent concentration–time curveIAUCdd2d6310 The intial area under the contrast agent concentration–time curve at 60 seconds11 after the onset time
IAUC60dd2d64
12 The intial area under the contrast agent concentration–time curve at 90 seconds13 after the onset time
IAUC90dd2d65
14 τ15 m. The mean intracellular water lifetime (τi). Used in the Shutter-Speed Model16 (SSM) of tracer kinetics.
tau_mdd2d66
17 v18 p. The fractional (not absolute) blood plasma volume per unit volume of tissue.
19 See Tofts et al, "Estimating Kinetic Parameters From Dynamic20 Contrast-Enhanced T1-Weighted MRI of a Diffusable Tracer: Standardized21 Quantities and Symbols", Journal of Magnetic Resonance Imaging, vol. 10,22 pp. 223–232, 1999.
vpdd2d67
23 A tracer diffusion kinetic model in which the permeability is assumed to be24 isodirectional.
25 See P. Tofts, "Modeling tracer kinetics in dynamic Gd-DTPA MR imaging",26 Journal of Magnetic Resonance Imaging, vol. 7, pp. 91–101, 1997.
Standard Tofts Modeldd2d71
27 A tracer diffusion kinetic model in which the permeability is not assumed to be28 isodirectional, and which includes the contribution of tracer in the blood plasma29 to the total tissue concentration.
30 See P. Tofts, "Modeling tracer kinetics in dynamic Gd-DTPA MR imaging",31 Journal of Magnetic Resonance Imaging, vol. 7, pp. 91–101, 1997.
Extended Tofts Modeldd2d72
32 A semiquantitative analysis of the contrast-enhancement concentration versus33 time curve that avoids the use of a pharmacokinetic model. E.g., integration34 to compute the initial area under the curve.
Model-freeconcentration-timequantitification
dd2d73
35 A tracer diffusion kinetic model that accounts for the tumor leakage profile36 during the first pass of contrast.
37 See Li, Ka-Loh, Xiao Ping Zhu, John Waterton, and Alan Jackson. "Improved38 3D Quantitative Mapping of Blood Volume and Endothelial Permeability in39 Brain Tumors." Journal of Magnetic Resonance Imaging 12, no. 2 (2000):40 347–357. doi:10.1002/1522-2586(200008)12:2<347::AID-JMRI19>3.0.CO;2-7.
First Pass Leakage Profile(FPLP)
dd2d74
41 A tracer diffusion kinetic model that does not assume that intercompartmental42 water molecule exchange is infinitely fast.
43 See Li, Xin, Wei Huang, Thomas E. Yankeelov, Alina Tudorica, William D.44 Rooney, and Charles S. Springer. “Shutter-Speed Analysis of Contrast Reagent45 Bolus-Tracking Data: Preliminary Observations in Benign and Malignant Breast46 Disease.” Magnetic Resonance in Medicine 53, no. 3 (2005): 724–29.47 doi:10.1002/mrm.20405.
Shutter-Speed Model (SSM)dd2d75
48 T1 measurement by Multiple Flip Angles (MFA) (variable saturation) methodT1 by Multiple Flip Anglesdd2d8149 T1 measurement by Inversion Recovery (IR) methodT1 by Inversion Recoverydd2d82
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1 NotesDefinitionCode MeaningCode Value2 Calculation was performed using a fixed value of T1 rather than a measured3 value. The value could be encoded as the value of (dd2d84, DCM, "T1 Used4 For Calculation").
T1 by Fixed Valuedd2d83
5 The fixed value of T1 used for a calculation.T1 Used For Calculationdd2d84
6 No Arterial Input Function was used.AIF Ignoreddd3d017 A population-averaged Arterial Input Function.Population Averaged AIFdd3d028 An Arterial Input Function computed from a user-defined Region of Interest.User-defined AIF ROIdd3d039 An Arterial Input Function computed from an automatically detected Region10 of Interest.
Automatically Detected AIFROI
dd3d04
11 A data-driven blind source separation (BSS) algorithm that estimates AIF from12 individuals without any presumed AIF model and initialization. See Lin,13 Yu-Chun, Tsung-Han Chan, Chong-Yung Chi, Shu-Hang Ng, Hao-Li Liu,14 Kuo-Chen Wei, Yau-Yau Wai, Chun-Chieh Wang, and Jiun-Jie Wang. "Blind15 Estimation of the Arterial Input Function in Dynamic Contrast-Enhanced MRI16 Using Purity Maximization." Magnetic Resonance in Medicine 68, no. 517 (November 1, 2012): 1439–49. doi:10.1002/mrm.24144.
Blind Estimation of AIFdd3d05
18 The time at which the concentration-time curve achieves its peak for the first19 time. Used as a concept name for a value or as a method. E.g., used as a20 method of calculation for BAT. See Shpilfoygel Med Phys 2008. doi:21 10.1118/1.1288669
Time of Peak Concentrationdd3d20
22 The nominal time at which arrival of a contrast bolus is detected, which is used23 as a reference point for subsequent calculations. Used as a concept name for24 a value or as a method. No specific computational method is implied by this25 general definition. Abbreviated BAT.
Bolus Arrival Timedd3d21
26 The time at which the concentration-time curve achieves half of its peak density27 for the first time. Used as a concept name for a value or as a method. E.g.,28 used as a method of calculation for BAT. See Shpilfoygel Med Phys 2008. doi:29 10.1118/1.1288669
Time of Leading Half-PeakConcentration
dd3d22
30 A method of determining BAT that involves computing the temporal derivative31 of the concentration-time curve and selecting the time when the temporal32 derivative exceeds a specified threshold. See Shpilfoygel Med Phys 2008. doi:33 10.1118/1.1288669
Temporal DerivativeExceeds Threshold
dd3d23
34 A threshold applied to the temporal derivative of the concentration-time curve.35 E.g., used to establish BAT. See Shpilfoygel Med Phys 2008. doi:36 10.1118/1.1288669
Temporal DerivativeThreshold
dd3d24
37 The maximum rate of signal intensity change within a measured region of a38 time-activity curve. See Boonsirikamchai, Piyaporn, Harmeet Kaur, Deborah39 A. Kuban, Edward Jackson, Ping Hou, and Haesun Choi. “Use of Maximum40 Slope Images Generated From Dynamic Contrast-Enhanced MRI to Detect41 Locally Recurrent Prostate Carcinoma After Prostatectomy: A Practical42 Approach.” American Journal of Roentgenology 198, no. 3 (March 1, 2012):43 W228–W236. doi:10.2214/AJR.10.6387.
Maximum Slopedd3d25
44 The maximum degree of signal intensity change within a measured region of45 a time-activity curve. See Boonsirikamchai, Piyaporn, Harmeet Kaur, Deborah46 A. Kuban, Edward Jackson, Ping Hou, and Haesun Choi. “Use of Maximum47 Slope Images Generated From Dynamic Contrast-Enhanced MRI to Detect48 Locally Recurrent Prostate Carcinoma After Prostatectomy: A Practical49 Approach.” American Journal of Roentgenology 198, no. 3 (March 1, 2012):50 W228–W236. doi:10.2214/AJR.10.6387.
Maximum Differencedd3d26
51 Tracer concentration in tissue. E.g., in a DCE-MR experiment, the concentration52 of contrast agent in mmol/l.
Tracer Concentrationdd3d27
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1 NotesDefinitionCode MeaningCode Value2 The degree to which a paramagnetic contrast agent can enhance the proton3 longitudinal relaxation rate constant (R1, 1/T1), normalized to the concentration4 of the contrast agent. Also referred to as r1. Typically expressed in units of5 l/mmol/s.
Contrast LongitudinalRelaxivity
dd4d01
6 The flow rate of blood perfusing a region as volume per mass per unit of time.Regional Blood Flowdd6d017 The volume of blood perfusing a region as as volume per mass.Regional Blood Volumedd6d028 The percent of the oxygen removed from the blood by tissue during its passage9 through the capillary network. For example, as measured by blood oxygenation10 level dependent (BOLD) MR. See He, Xiang, and Dmitriy A. Yablonskiy.11 “Quantitative BOLD: Mapping of Human Cerebral Deoxygenated Blood Volume12 and Oxygen Extraction Fraction: Default State.” Magnetic Resonance in13 Medicine 57, no. 1 (2007): 115–26.
Oxygen Extraction Fractiondd6d03
14 The longitiudinal relaxation rate constant. The inverse of longitudinal relaxation15 time, i.e., R1 = 1/T1.
R1dd7d01
16 The transverse relaxation rate constant. The inverse of transverse relaxation17 time, i.e., R2 = 1/T2.
R2dd7d02
18 Amend DICOM PS3.16 - Content Mapping Resource - Controlled Terminology Definitions to make suitable for use both as Abstract19 Multi-dimensional Image Model Component Semantics and Quantity Descriptor:
21 NotesDefinitionCode MeaningCode Value22 ............23 A quantitative numerical statement of the relative attenuation of the24 X-Ray beam at a specified point. Coefficient that describes the25 fraction of a beam of X-Rays or gamma rays that is absorbed or26 scattered per unit thickness of the absorber. This value basically27 accounts for the number of atoms in a cubic cm volume of material28 and the probability of a photon being scattered or absorbed from29 the nucleus or an electron of one of these atoms. Usually expressed30 in Hounsfield units [referred to as CT Number in Fraser and Pare].
Attenuation Coefficient112031
31 ............32 The image is derived by calculating mean transit time valuesThe33 time required for blood to pass through a region of tissue.
Mean Transit Time113052
34 ............35 The image isValues are derived by calculating negative enhancement36 integral values.
Negative Enhancement37 Integral
113054
38 The image is derived by calculating regional cerebral blood flow39 valuesThe flow rate of blood perfusing a region of the brain as40 volume per mass per unit of time.
Regional Cerebral Blood Flow113055
41 The image is derived by calculating regional cerebral blood volume42 valuesThe volume of blood perfusing a region of brain as as43 volume per mass.
Regional Cerebral Blood44 Volume
113056
45 ............46 The image isValues are derived by calculating proton density values.Proton Density map11305847 The image isValues are derived by calculating signal change values.Signal Change Map11305948 ............49 The image isValues are derived by calculating T1 values.T1 Map113063
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1 NotesDefinitionCode MeaningCode Value2 The image isValues are derived by calculating T2* values.T2* Map1130643 The image isValues are derived by calculating T2 values.T2 Map1130654 The image isValues are derived by calculating values based on the5 time course of signal.
Time Course of Signal113066
6 ............7 The image is derived by calculating values based on the time to8 peakThe time from the start of the contrast agent injection to the9 maximum enhancement value .
Time To Peak map113069
10 ............11 Signal intensity of a Spin tagging Perfusion MR image. Spin tagging12 is a technique for the measurement of blood perfusion, based on13 magnetically labeled arterial blood water as an endogenous tracer.
Spin Tagging Perfusion MRSignal Intensity
110800
14 Signal intensity of a Contrast Agent Angio MR image.Contrast Agent Angio MR15 Signal Intensity
110801
16 Signal intensity of a Time-of-flight (TOF) MR image. Time-of-flight17 (TOF) is based on the phenomenon of flow-related enhancement of18 spins entering into an imaging slice. As a result of being unsaturated,19 these spins give more signal that surrounding stationary spins.
Time Of Flight Angio MRSignal Intensity
110802
20 Signal intensity of a Proton Density Weighted MR image. All MR images21 have intensity proportional to proton density. Images with very little T122 or T2 weighting are called 'PD-weighted'.
Proton Density Weighted MRSignal Intensity
110803
23 Signal intensity of T1 Weighted MR image. A T1 Weighted MR image24 is created typically by using short TE and TR times.
T1 Weighted MR SignalIntensity
110804
25 Signal intensity of a T2 Weighted MR image. T2 Weighted image26 contrast state is approached by imaging with a TR long compared to27 tissue T1 (to reduce T1 contribution to image contrast) and a TE28 between the longest and shortest tissue T2s of interest.
T2 Weighted MR SignalIntensity
110805
29 Signal intensity of a T2* Weighted MR image. The T2* phenomenon30 results from molecular interactions (spin spin relaxation) and local31 magnetic field non-uniformities, which cause the protons to precess at32 slightly different frequencies.
T2* Weighted MR SignalIntensity
110806
33 Signal intensity of a Field Map MR image. A Field Map MR image34 provides a direct measure of the B35 0 inhomogeneity at each point in the36 image.
Field Map MR Signal Intensity110807
37 ............38 Signal intensity of a T1 Weighted Dynamic Contrast Enhanced MR39 image. A T1 Weighted Dynamic Contrast Enhanced MR image reflects40 the dynamics of diffusion of the exogenous contrast media from the41 blood pool into the extra vascular extracellular space (EES) of the brain42 at a rate determined by the blood flow to the tissue, the permeability43 of the Brain Blood Barrier (BBB), and the surface area of the perfusing44 vessels.
45 Signal intensity of a T2 Weighted Dynamic Contrast Enhanced MR46 image. A T2 Weighted Dynamic Contrast Enhanced MR image reflects47 the T2 of tissue decrease as the Gd contrast agent bolus passes48 through the brain.
49 Signal intensity of a T2* Weighted Dynamic Contrast Enhanced MR50 image. A T2* Weighted Dynamic Contrast Enhanced MR image reflects51 the T2* of tissue decrease as the Gd contrast agent bolus passes52 through the brain.
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1 NotesDefinitionCode MeaningCode Value2 Signal intensity of a Blood Oxygenation Level image. BOLD imaging3 is sensitive to blood oxygenation (but also to cerebral blood flow and4 volume). This modality is essentially used for detecting brain activation5 (functional MR).
Blood Oxygenation Level110819
6 ............7 Velocity of tissue based on Doppler measurements.Tissue Velocity1108278 Velocity of blood flow based on Doppler measurements.Flow Velocity1108289 Statistical variance of blood velocity relative to mean.Flow Variance11082910 Scalar value related to the elastic properties of the tissue.Elasticity11083011 Scalar value related to the volume of blood perfusing into tissue.Perfusion11083112 Decrease in the number of photons in an X-Ray beam due to13 interactions with the atoms of a material substance. Attenuation is due14 primarily to two processes, absorption and scattering.
Coefficient that describes the fraction of a beam of X-Rays or gammarays that is absorbed or scattered per unit thickness of the absorber.This value basically accounts for the number of atoms in a cubic cmvolume of material and the probability of a photon being scattered orabsorbed from the nucleus or an electron of one of these atoms.
X-Ray Attenuation Coefficient110851
21 Signal intensity of an MR image, not otherwise specified.MR signal intensity110852
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