Digital Imaging and Communications
`in Medicine (DICOM)
`
`Supplement 11
`
`Radiotherapy Objects
`
`Status: Final Text, 4 June 1997
`
`Page 1 of 105
`
`Elekta Exhibit 1048
`
`

`
`DICOM RT Supplement
`
`TABLE OF CONTENTS
`
`Part 3 Addendum Radiotherapy Information Object Definitions ................................................................ 1
`Foreword ................................................................................................................................................. 2
`Scope and Field of Application................................................................................................................. 3
`A.U RT IMAGE INFORMATION OBJECT DEFINITION .................................................................. 11
`A.U.1 RT Image IOD Description............................................................................................... 11
`A.U.2 RT Image IOD entity-relationship model .......................................................................... 11
`A.U.3 RT Image IOD Module Table........................................................................................... 12
`A.V RT DOSE INFORMATION OBJECT DEFINITION.................................................................... 14
`A.V.1 RT Dose IOD Description ................................................................................................ 14
`A.V.2 RT Dose IOD entity-relationship model ............................................................................ 14
`A.V.3 RT Dose IOD Module Table............................................................................................. 15
`A.W RT STRUCTURE SET INFORMATION OBJECT DEFINITION ............................................... 17
`A.W.1 RT Structure Set IOD Description ................................................................................... 17
`A.W.2 RT Structure Set IOD entity-relationship model............................................................... 17
`A.W.3 RT Structure Set IOD Module Table ............................................................................... 18
`A.X RT PLAN INFORMATION OBJECT DEFINITION..................................................................... 19
`A.X.1 RT Plan IOD Description ................................................................................................. 19
`A.X.2 RT Plan IOD entity-relationship model ............................................................................. 19
`A.X.3 RT Plan IOD Module Table.............................................................................................. 20
`C.7.3.1.1.1 Modality ............................................................................................................ 22
`C.8.X Radiotherapy................................................................................................................... 23
`C.8.X.1 RT Series Module .................................................................................................. 24
`C.8.X.2 RT Image Module................................................................................................... 25
`C.8.X.3 RT Dose Module .................................................................................................... 34
`C.8.X.4 RT DVH Module ..................................................................................................... 39
`C.8.X.5 Structure Set Module.............................................................................................. 41
`C.8.X.6 ROI Contour Module .............................................................................................. 44
`C.8.X.7 RT Dose ROI Module ............................................................................................. 46
`C.8.X.8 RT ROI Observations Module................................................................................. 47
`C.8.X.9 RT General Plan Module ........................................................................................ 50
`C.8.X.10 RT Prescription Module ........................................................................................ 52
`C.8.X.11 RT Tolerance Tables Module................................................................................ 55
`C.8.X.12 RT Patient Setup Module ..................................................................................... 57
`C.8.X.13 RT Fraction Scheme Module ................................................................................ 59
`C.8.X.14 RT Beams Module................................................................................................ 64
`C.8.X.15 RT Brachy Application Setups Module.................................................................. 80
`C.8.X.16 Approval Module .................................................................................................. 90
`Part 4 Addendum Radiotherapy Storage SOP Classes .......................................................................... 91
`B.5 STANDARD SOP CLASSES..................................................................................................... 92
`Part 6 Addendum Radiotherapy Data Dictionary .................................................................................... 93
`
`Final Text, 4 June 1997
`
`i
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`Page 2 of 105
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Digital Imaging and Communications
`in Medicine (DICOM)
`
`Part 3 Addendum Radiotherapy
`Information Object Definitions
`
`Final Text, 4 June 1997
`
`1
`
`Page 3 of 105
`
`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #1
`Standard DICOM foreword - will remain unchanged in DICOM Part 3 FOREWORD
`
`Foreword
`
`ACR (the American College of Radiology) and NEMA (the National Electrical Manufacturers Association)
`formed a joint committee to develop a Standard for Digital Imaging and Communications in Medicine.
`This DICOM Standard was developed according to the NEMA Procedures.
`
`This Supplement to the Standard is being developed in conjunction with IEC Subcommittee 62C Working
`Group 1 (see document IEC 62C/124/NWP, January 1995), CEN TC251 Working Group 4, and the
`AAPM.
`
`The DICOM standard is structured as a multi-part document using the guidelines established in the
`following document:
`
`- ISO/IEC Directives, 1989 Part 3 - Drafting and Presentation of International Standards.
`
`This document is a Supplement to the DICOM Standard. It is an extension to Part 3, 4 and 6 of the
`published DICOM Standard which consists of the following parts:
`
`Part 1
`Part 2
`Part 3
`Part 4
`Part 5
`Part 6
`Part 7
`Part 8
`Part 9
`Part 10
`Part 11
`Part 12
`Part 13
`
`—
`—
`—
`—
`—
`—
`—
`—
`—
`—
`—
`—
`—
`
`Introduction and Overview
`Conformance
`Information Object Definitions
`Service Class Specifications
`Data Structures and Encoding
`Data Dictionary
`Message Exchange
`Network Communication Support for Message Exchange
`Point-to-Point Communication Support for Message Exchange
`Media Storage and File Format
`Media Storage Application Profiles
`Media Formats and Physical Media
`Print Management Point-to-Point Communication Support
`
`These Parts are independent but related documents. Their development level and approval status may
`differ. Additional parts may be added to this multi-part standard. PS3.1 should be used as the base
`reference for the current parts of this standard.
`
`Final Text, 4 June 1997
`
`2
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #2
`Introduction to Radiotherapy Objects - will not appear in final standard
`
`Scope and Field of Application
`
`This supplement to the DICOM Standard defines a number of information objects applicable to the
`domain of radiation oncology. The intent of these objects is to support the transfer of radiotherapy-related
`data between devices found within and outside a radiotherapy department. They are not, however,
`intended to support the management of the transferred data, a function which may be addressed in future
`revisions of the DICOM standard.
`
`This task of process management has not been addressed in the current draft due to the absence of a
`consistent process model for a radiotherapy department, especially in an international context. As a
`result, the radiotherapy information objects contain a large number of conditional and optional data
`elements. Essentially the objects are intended to be used as “containers” for related radiotherapy data,
`with data being added as the object flows through the department.
`
`This Supplement specifies the following information objects:
`
`1. A DICOM Image Information Object for Radiotherapy. It specifies the semantic content of RT
`Images. It is commonly abbreviated the RT Image IOD. It also includes the corresponding Storage
`SOP Class so that this IOD can be used in Network and Media Storage exchanges. The scope of the
`RT Image IOD is radiotherapy images which have been obtained on a conic imaging geometry, such
`as that found on conventional simulators and portal imaging devices. It can also be used for
`calculated images using the same geometry, such as digitally reconstructed radiographs (DRRs).
`
`2. A DICOM Dose Information Object for Radiotherapy. It specifies the semantic content of RT Doses.
`It is commonly abbreviated the RT Dose IOD. It also includes the corresponding Storage SOP Class
`so that this IOD can be used in Network and Media Storage exchanges. The scope of the RT Dose
`IOD is radiotherapy dose distributions which have been calculated on a radiotherapy treatment
`planning system, represented as two or three dimensional dose grids, groups of named or unnamed
`dose points, isodose curves, and dose-volume histograms (DVHs).
`
`3. A DICOM Structure Set Information Object for Radiotherapy. It specifies the semantic content of RT
`Structure Sets. It is commonly abbreviated the RT Structure Set IOD. It also includes the
`corresponding Storage SOP Class so that this IOD can be used in Network and Media Storage
`exchanges. The scope of the RT Structure Set IOD is radiotherapy patient-related structures which
`have been identified on devices such as CT scanners, virtual simulation workstations, or treatment
`planning systems.
`
`4. A DICOM Plan Information Object for Radiotherapy. It specifies the semantic content of RT
`(Treatment) Plans. It is commonly abbreviated the RT Plan IOD. It also includes the corresponding
`Storage SOP Class so that this IOD can be used in Network and Media Storage exchanges. The
`scope of the RT Plan IOD is geometric and dosimetric data specifying a course of external beam
`and/or brachytherapy treatment.
`
`Since this document proposes changes to existing Parts of DICOM the reader should have a working
`understanding of the Standard.
`
`Final Text, 4 June 1997
`
`3
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`This proposed Supplement includes a number of Addenda to existing Parts of DICOM:
`
`1. Part 3 Addenda (Extension to the body, Annex A, B, C and D)
`
`2. Part 4 Addenda (Extension to Annex B)
`
`3. Part 6 Addenda (Extension to Section 6 and Annex A)
`
`Final Text, 4 June 1997
`
`4
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`Page 6 of 105
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #3
`Add to Section 2:
`
`2
`
`Normative references
`
`IEC Standard 1217, Radiotherapy Equipment - Coordinates, Movements and Scales (Reference CEI/IEC
`1217: 1996)
`
`ICRU Report 50, Prescribing, Recording, and Reporting Photon Beam Therapy, International
`Commission on Radiation Units and Measurements, 1993
`
`Final Text, 4 June 1997
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`5
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`Page 7 of 105
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #4
`After Section 3.8 add the following:
`
`3.X
`
`Radiotherapy
`
`This Part of the Standard is based on the concepts developed in IEC 1217 and makes use of the
`following terms defined in it:
`a)
`FIXED REFERENCE system
`b) GANTRY system
`c)
`BEAM LIMITING DEVICE system
`d) WEDGE FILTER system
`e) X-RAY IMAGE RECEPTOR system
`f)
`PATIENT SUPPORT system
`g)
`TABLE TOP ECCENTRIC system
`h)
`TABLE TOP system
`
`Final Text, 4 June 1997
`
`6
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #5
`In Section 4 add the following:
`
`4
`
`Symbols and abbreviations
`
`BEV
`Brachy
`CC
`CTV
`CW
`DRR
`DVH
`GTV
`Gy
`ICRU
`IEC
`MeV
`MLC
`MU
`MV
`PTV
`R&V
`ROI
`RT
`SAD
`SID
`
`Beam’s-eye view
`Brachytherapy
`Counter-clockwise
`Clinical target volume
`Clockwise
`Digitally-reconstructed radiograph
`Dose-volume histogram
`Gross tumor volume
`Gray
`International Commission on Radiation Units
`International Electrotechnical Commission
`Mega electron Volt
`Multileaf (multi-element) collimator
`Monitor unit
`Megavolt
`Planning target volume
`Record and verify
`Region of interest
`Radiotherapy
`Source-axis distance
`Source-image distance
`
`Final Text, 4 June 1997
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #6
`Add in Figure 7-2
`
`Patient IOD
`
`1
`
`ref
`
`1-n
`Study IOD
`
`1
`
`ref
`
`0-n
`
`ref
`
`0-n
`
`1
`
`ref
`
`1
`
`ref
`
`0-n
`
`1
`
`ref
`
`0-n
`
`Image IOD
`
`0-n
`
`1
`
`ref
`
`0-n
`
`0-n
`
`RT Image IOD
`
`RT Dose IOD
`
`0-n
`
`0-1
`
`ref
`
`RT Structure
`Set IOD
`
`0-1
`
`ref
`
`0-n
`
`RTPlan IOD
`
`1
`
`1
`
`11
`
`0-n
`
`0-n
`
`ref
`
`ref
`
`0-n
`
`(reference images)
`
`0-n
`
`Figure 7-2—DICOM information model (RT extensions)
`
`Final Text, 4 June 1997
`
`8
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #7
`Add in Table A.1-1 - all modifications to existing table are in BOLD font
`
`Table A.1-1—Composite Information Object Modules Overview
`
`IODs
`Modules
`Patient
`Patient Summary
`General Study
`Patient Study
`Study Content
`General Series
`CR Series
`NM Series
`RT Series
`Frame Of Reference
`US Frame of Ref.
`General Equipment
`NM Equipment
`SC Equipment
`General Image
`Image Plane
`Image Pixel
`Contrast/Bolus
`Cine
`Multi-frame
`CR Image
`CT Image
`MR Image
`NM Image
`NM SPECT
`NM Multi-Gated
`US Region Calibration
`US Image
`SC Image
`RT Image
`RT Dose
`RT DVH
`Structure Set
`ROI Contour
`RT Dose ROI
`RT ROI Observations
`RT General Plan
`RT Prescription
`RT Tolerance Tables
`RT Patient Setup
`RT Fraction Scheme
`
`RT Image RT Dose RT Struct
`Set
`M
`
`M
`
`M
`
`M
`U
`
`M
`U
`
`M
`
`M
`
`M
`C
`C
`C
`
`M
`
`M
`U
`
`M
`M
`
`M
`
`C
`C
`C
`
`C
`
`M
`U
`C
`C
`C
`
`M
`U
`
`M
`
`M
`
`M
`M
`
`M
`
`RT Plan
`
`M
`
`M
`U
`
`M
`
`M
`
`M
`U
`U
`U
`U
`
`Final Text, 4 June 1997
`
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`RT Image RT Dose RT Struct
`Set
`
`RT Plan
`
`IODs
`Modules
`RT Beams
`RT Brachy Application Setups
`Approval
`Overlay Identification
`Overlay Plane
`Multi-frame Overlay
`Curve Identification
`Curve
`Audio
`Modality LUT
`VOI LUT
`LUT Identification
`M
`M
`M
`M
`SOP Common
`* The notation next to M and U indicates a special condition for these modules. Refer to the
`corresponding Information Object Definitions in this Annex for details.
`
`U
`
`U
`U
`U
`U
`
`U
`
`U
`
`U
`U
`
`U
`U
`
`C
`C
`U
`
`U
`
`Final Text, 4 June 1997
`
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`Page 12 of 105
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Item #8
`After Section A.14 add the following:
`
`A.U
`
`RT IMAGE INFORMATION OBJECT DEFINITION
`
`RT Image IOD Description
`A.U.1
`The focus for this Radiotherapy Image IOD (RT Image IOD) is to address the requirements for image
`transfer found in general radiotherapy applications performed on conventional simulators, virtual
`simulators, and portal imaging devices. Such images have a conical imaging geometry and may either be
`acquired directly from the device, or digitized using a film digitizer. They may or may not have
`superimposed curves describing beam limiting device (collimator) openings, beam modifying devices,
`patient structures and target volumes. Numeric beam data parameters may also be recorded with the
`image, indicating the parameter values at the time the image was taken or created.
`
`RT Image IOD entity-relationship model
`A.U.2
`The E-R model for the RT Image IOD is illustrated in Figure A.U-1.
`
`Patient
`
`1
`
`is
`the subject
`of
`
`1,n
`
`Study
`
`1
`
`contains
`
`1,n
`
`Series
`
`1
`
`contains
`
`0,n
`
`Image
`
`spatially
`defines
`
`1
`
`0,n
`
`creates
`
`1
`
`1,n
`
`Frame of Reference
`
`Equipment
`
` Figure A.U-1—DICOM RT Image IOD information model
`
`Final Text, 4 June 1997
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`A.U.3
`
`RT Image IOD Module Table
`
`Table A.U.3-1—RT Image IOD Modules
`
`IE
`Patient
`Study
`
`Series
`Frame of
`Reference
`Equipment
`Image
`
`Module
`Patient
`General Study
`Patient Study
`RT Series
`Frame of Reference
`
`General Equipment
`General Image
`Image Pixel
`Contrast/bolus
`
`Cine
`
`Multi-Frame
`
`RT Image
`Modality LUT
`VOI LUT
`Approval
`Curve
`Audio
`SOP Common
`
`Reference
`C.7.1.1
`C.7.2.1
`C.7.2.2
`C.8.X.1
`C.7.4.1
`
`C.7.5.1
`C.7.6.1
`C.7.6.3
`C.7.6.4
`
`C.7.6.5
`
`C.7.6.6
`
`C.8.X.2
`C.11.1
`C.11.2
`C.8.X.16
`C.10.2
`C.10.3
`C.12.1
`
`Usage
`M
`M
`U
`M
`U
`
`M
`M
`M
`C-Required if contrast media
`was used in this image.
`C - Required if multi-frame
`image is a cine image.
`C - Required if pixel data is
`multi-frame data.
`M
`U
`U
`U
`U
`U
`M
`
`Notes:
`
`1. The inclusion of the Multi-Frame module allows for the expression of time-dependent image series or
`multiple exposures of identical beam geometries (i.e. multiple exposure portal images). If a time-
`dependent series of images (such as port images or DRRs) is represented the Cine module is used
`to indicate this. This would subsequently allow analysis of patient movement during treatment.
`Multiple exposure images allow individual images of treatment ports and open field ports to be
`grouped into a single multi-frame image.
`
`2. The Modality LUT module has been included to allow the possibility of conversion between portal
`image pixel values and dose transmitted through the patient. The VOI LUT module has been included
`to allow the possibility of translation between stored pixel values (after the Modality LUT has been
`applied if specified) and display levels.
`
`3. The Curve module has been included to allow the possibility of storing one or more curves overlaid
`with a given image. Generally these curves would represent patient structures, target volumes, or
`beam limiting device (collimator) openings, although they could also be used to store other data such
`as axis information. Such curves would be stored in pixel units (i.e. the coordinates would represent
`pixel indices in the image data). For example, patient structures might have the following attribute
`assignments:
`
`Final Text, 4 June 1997
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`12
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`Curve Dimensions (50xx, 0005)
`Number of Points (50xx, 0010)
`Type of Data (50xx, 0020)
`Data Value Representation (50xx, 0103)
`Curve Data (50xx, 3000)
`Curve Description (50xx,0022)
`
`= 2
`= Number of data points in curve
`= ROI
`= US (unsigned short)
`= (x,y) pixel coordinates
`= Structure/Target name
`
`Note that there is no facility for representing multi-frame curves (i.e. all curves are interpreted as
`being related to the first image frame in a multi-frame image). Curves other than patient structures
`might also be represented using the HIST, POLY or TABL curve types (see P3.3, C.10.2.1).
`
`4. The Equipment module contains information describing the equipment used to acquire or generate
`the RT Image (such as a portal imager, conventional simulator or treatment planning system).
`However, the equipment attributes in the RT Image module describe the equipment on which the
`treatment has been or will be given, typically an electron accelerator.
`
`5. For RT Images which contain no relevant pixel data, such as BEV images without DRR information,
`Pixel Data (7FE0,0010) should be filled with a sequence of zeros.
`
`6.
`
`The Frame of Reference module has been included to allow the indication of spatial association of
`two or more RT Image instances (e.g. where the images have been acquired in the same frame of
`reference, or have been resampled to share the same frame of reference). If the Frame of
`Reference occurs within a SOP Instance within a given series, then all SOP Instances within that
`series will be spatially related. For example, two RT Images may share the same Frame of
`Reference if they are located on the same physical plane, as determined by the treatment machine
`Gantry Angle (300A,011E) and source to image plane distance specified by RT Image SID
`(3002,0026).
`
`Final Text, 4 June 1997
`
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`A.V
`
`RT DOSE INFORMATION OBJECT DEFINITION
`
`RT Dose IOD Description
`A.V.1
`The focus for this Radiotherapy Dose IOD (RT Dose IOD) is to address the requirements for transfer of
`dose distributions calculated by radiotherapy treatment planning systems. These distributions may be
`represented as 2D or 3D grids, as isodose curves, or as named or unnamed dose points scattered
`throughout the volume. This IOD may also contain dose-volume histogram data, single or multi-frame
`overlays, audio annotations, and application-defined lookup tables. This IOD does not provide for
`definition of doses in beam or other coordinate systems. The application is responsible for transforming
`data in other, non-patient based coordinate systems to the patient based coordinate system described in
`C.7.6.2.1.1.
`
`RT Dose IOD entity-relationship model
`A.V.2
`The E-R model for the RT Dose IOD is illustrated in Figure A.V-1.
`
`Patient
`
`1
`
`is
`the subject
`of
`
`1,n
`
`Study
`
`1
`
`contains
`
`1,n
`
`Series
`
`1
`
`contains
`
`0,n
`
`Dose
`
`spatially
`defines
`
`1
`
`0,n
`
`creates
`
`1
`
`1,n
`
`Frame of Reference
`
`Equipment
`
` Figure A.V-1—DICOM RT Dose IOD information model
`
`Final Text, 4 June 1997
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`

`
`DICOM RT Supplement
`
`RT IODs
`
`A.V.3
`
`RT Dose IOD Module Table
`
`Table A.V.3-1—RT Dose IOD Modules
`
`IE
`Patient
`Study
`
`Series
`Frame of
`Reference
`Equipment
`Dose
`
`Module
`Patient
`General Study
`Patient Study
`RT Series
`Frame of Reference
`
`General Equipment
`General Image
`
`Image Plane
`
`Image Pixel
`
`Multi-Frame
`
`Overlay Plane
`Multi-Frame Overlay
`Modality LUT
`RT Dose
`RT DVH
`Structure Set
`
`ROI Contour
`
`RT Dose ROI
`
`Audio
`SOP Common
`
`Reference
`C.7.1.1
`C.7.2.1
`C.7.2.2
`C.8.X.1
`C.7.4.1
`
`Usage
`M
`M
`U
`M
`M
`
`C.7.5.1
`C.7.6.1
`
`C.7.6.2
`
`C.7.6.3
`
`C.7.6.6
`
`C.9.2
`C.9.3
`C.11.1
`C.8.X.3
`C.8.X.4
`C.8.X.5
`
`C.8.X.6
`
`C.8.X.7
`
`C.10.3
`C.12.1
`
`M
`C - Required if dose data
`contains grid-based doses.
`C - Required if dose data
`contains grid-based doses.
`C - Required if dose data
`contains grid-based doses.
`C - Required if dose data
`contains grid-based doses and
`pixel data is multi-frame data.
`U
`U
`U
`M
`U
`C - Required if dose data
`contains dose points or
`isodose curves
`C - Required if dose data
`contains dose points or
`isodose curves
`C - Required if dose data
`contains dose points or
`isodose curves
`U
`M
`
`Notes:
`
`1. Within the RT Dose IOD, the RT Dose module supports 2D and 3D dose grids. The Structure Set,
`ROI Contour and RT Dose ROI modules together support isodose curves and points, and the RT
`DVH module supports dose-volume histogram data. They are not mutually exclusive: all four
`representations may be included in a single instance of the object or they may be included in any
`combination. Product Conformance Statements should clearly state which of these mechanisms is
`supported and under what conditions.
`
`2. The RT Dose IOD has been defined as a composite IOD, separate from the RT Plan IOD. This has
`been done for the following reasons:
`–
`To allow for the multiplicity of possible dose calculations using beam models for the same basic
`plan.
`To avoid undesirable transmission of large amounts of data with the treatment plan.
`
`–
`
`Final Text, 4 June 1997
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`DICOM RT Supplement
`
`RT IODs
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`–
`
`To accommodate the fact that CT Simulation and other “beam geometry” generating devices
`which use the RT Plan IOD do not have or require access to this data, either for transmission or
`storage.
`
`Final Text, 4 June 1997
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`DICOM RT Supplement
`
`RT IODs
`
`A.W
`
`RT STRUCTURE SET INFORMATION OBJECT DEFINITION
`
`RT Structure Set IOD Description
`A.W.1
`The focus for this Radiotherapy Structure Set IOD (RT Structure Set IOD) is to address the requirements
`for transfer of patient structures and related data defined on CT scanners, virtual simulation workstations,
`treatment planning systems and similar devices. This IOD may also contain audio curve annotations.
`
`RT Structure Set IOD entity-relationship model
`A.W.2
`The E-R model for the RT Structure Set IOD is illustrated in Figure A.W-1.
`
`Patient
`
`1
`
`is
`the subject
`of
`
`1,n
`
`Study
`
`1
`
`contains
`
`1,n
`
`Series
`
`1
`
`contains
`
`0,n
`
`Structure Set
`
`1,n
`
`creates
`
`1
`
`Equipment
`
` Figure A.W-1—DICOM RT Structure Set IOD information model
`
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`
`RT IODs
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`A.W.3
`
`RT Structure Set IOD Module Table
`
`Table A.W.3-1—RT Structure Set IOD Modules
`
`IE
`Patient
`Study
`
`Series
`Equipment
`Structure Set
`
`Module
`Patient
`General Study
`Patient Study
`RT Series
`General Equipment
`Structure Set
`ROI Contour
`RT ROI Observations
`Approval
`Audio
`SOP Common
`
`Reference
`C.7.1.1
`C.7.2.1
`C.7.2.2
`C.8.X.1
`C.7.5.1
`C.8.X.5
`C.8.X.6
`C.8.X.8
`C.8.X.16
`C.10.3
`C.12.1
`
`Usage
`M
`M
`U
`M
`M
`M
`M
`M
`U
`U
`M
`
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`RT IODs
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`A.X
`
`RT PLAN INFORMATION OBJECT DEFINITION
`
`RT Plan IOD Description
`A.X.1
`The focus for this Radiotherapy Plan IOD (RT Plan IOD) is to address the requirements for transfer of
`treatment plans generated by manual entry, a virtual simulation system, or a treatment planning system
`before or during a course of treatment. Such plans may contain fractionation information, and define
`external beams and/or brachytherapy application setups. This IOD may also contain audio curve
`annotations.
`
`RT Plan IOD entity-relationship model
`A.X.2
`The E-R model for the RT Plan IOD is illustrated in Figure A.X-1.
`
`Patient
`
`1
`
`is
`the subject
`of
`
`1,n
`
`Study
`
`1
`
`contains
`
`1,n
`
`Series
`
`1
`
`contains
`
`0,n
`
`Plan
`
`1,n
`
`creates
`
`1
`
`Equipment
`
` Figure A.X-1—DICOM RT Plan IOD information model
`
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`
`RT IODs
`
`A.X.3
`
`RT Plan IOD Module Table
`
`Table A.X.3-1—RT Plan IOD Modules
`
`IE
`Patient
`Study
`
`Series
`Equipment
`Plan
`
`Module
`Patient
`General Study
`Patient Study
`RT Series
`General Equipment
`RT General Plan
`RT Prescription
`RT Tolerance Tables
`RT Patient Setup
`RT Fraction Scheme
`RT Beams
`
`Reference
`C.7.1.1
`C.7.2.1
`C.7.2.2
`C.8.X.1
`C.7.5.1
`C.8.X.9
`C.8.X.10
`C.8.X.11
`C.8.X.12
`C.8.X.13
`C.8.X.14
`
`RT Brachy Application
`Setups
`
`C.8.X.15
`
`Approval
`Audio
`SOP Common
`
`C.8.X.16
`C.10.3
`C.12.1
`
`A.X.3.1 RT FRACTION SCHEME MODULE
`
`Usage
`M
`M
`U
`M
`M
`M
`U
`U
`U
`U
`C - Required if RT Fraction
`Scheme Module exists and
`Number of Beams
`(300A,0080) is greater than
`zero for one or more fraction
`groups
`C - Required if RT Fraction
`Scheme Module exists and
`Number of Brachy Application
`Setups (300A,00A0) is greater
`than zero for one or more
`fraction groups
`U
`U
`M
`
`The RT Fraction Scheme module is structured to be used together with the RT Beams or RT Brachy
`Application Setups module. If beams are referenced in the RT Fraction Scheme module, all such beams
`shall be included in the RT Beams module if it is present. Similarly, if brachy application setups are
`referenced in the RT Fraction Scheme module, all such setups shall be included in the RT Brachy
`Application Setups module if it is present. However, the RT Fraction Scheme module can be used without
`the RT Beams or RT Brachy Application Setups modules if no beams or brachy application setups are
`referenced, and the RT Beams or RT Brachy Application Setups modules can also be used without the
`RT Fraction Scheme module if no fraction scheme information is available.
`
`A.X.3.2 RT PRESCRIPTION MODULE
`
`The RT Prescription module provides for the inclusion of dose prescription information pertinent to the
`complete plan, which may comprise several fraction schemes, themselves consisting of many beams.
`
`A.X.3.3 RT TOLERANCE TABLES MODULE
`
`The RT Tolerance Tables module provides information concerning machine tolerances as they apply to
`the whole treatment plan. Tolerances are applied by reference to a tolerance table within the RT
`Tolerance Tables module for beams contained within the RT Beams module.
`
`Final Text, 4 June 1997
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`RT IODs
`
`A.X.3.4 RT PATIENT SETUP MODULE
`
`The RT Patient Setup module provides information concerning patient setup parameters and fixation
`devices as they apply to the whole treatment plan. Patient setup information within the RT Patient Setup
`module is referenced by beams contained within the RT Beams module.
`
`Final Text, 4 June 1997
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`DICOM RT Supplement
`
`RT IODs
`
`Item #9
`Add new Defined Terms to Section C.7.3.1.1.1
`
`Modality
`C.7.3.1.1.1
`The following Defined Terms shall be added:
`
`RTIMAGE = Radiotherapy Image
`RTDOSE
`= Radiotherapy Dose
`RTSTRUCT = Radiotherapy Structure Set
`RTPLAN
`= Radiotherapy Plan
`
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`DICOM RT Supplement
`
`RT IODs
`
`Item #10
`Add new Sections C.8.X and C.8.X.1 to C.8.X.16
`
`C.8.X
`Radiotherapy
`This section describes Radiotherapy-specific modules.
`
`Modules defined here make reference to “IEC” coordinate systems and standards. These standards are
`defined in IEC Standard 1217, “Radiotherapy Equipment - Coordinates, Movements and Scales”
`(Reference CEI/IEC 1217: 1996).
`
`Many of the dosimetry concepts referred to in this document can be found in ICRU Report 50,
`Prescribing, Recording, and Reporting Photon Beam Therapy, International Commission on Radiation
`Units and Measurements, 1993.
`
`Final Text, 4 June 1997
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`RT IODs
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`C.8.X.1 RT Series Module
`There exist significant differences in the manner in which RT objects as compared to diagnostic objects.
`An RT object can be one of several types, and a series of a given object type may be created over a
`temporal span of several weeks. The RT Series Module has been created to satisfy the requirements of
`the standard DICOM Query/Retrieve model while including only those attributes relevant to the
`identification and selection of radiotherapy objects.
`Table C.8.X.1-1 - RT Series Module
`
`Attribute Name
`Modality
`
`Tag
`(0008,0060)
`
`Series Instance UID
`Series Number
`Series Description
`Referenced Study Component
`Sequence
`
`(0020,000E)
`(0020,0011)
`(0008,103E)
`(0008,1111)
`
`>Referenced SOP Class UID
`
`(0008,1150)
`
`>Referenced SOP Instance UID
`
`(0008,1155)
`
`1
`2
`3
`3
`
`Type Attribute Description
`1
`Type of equipment that originally
`acquired the data. Enumerated Values:
`RTIMAGE = RT Image
`RTDOSE = RT Dose
`RTSTRUCT = RT Structure Set
`RTPLAN = RT Plan
`See C.8.X.1.1.
`Unique identifier of the series.
`A number that identifies this series.
`User provided description of the series.
`Uniquely identifies the Study Component
`SOP Instances to which the series is
`related. One or more items may be
`included in this sequence.
`Uniquely identifies the referenced SOP
`Class. Required if Referenced Study
`Component (0008,1111) is sent.
`Uniquely identifies the referenced SOP
`Instance. Required if Referenced Study
`Component (0008,1111) is sent.
`
`1C
`
`1C
`
`C.8.X.1.1 Modality
`
`The Enumerated Value for Modality (0008,0060) shall determined by the IOD:
`
`if RT Image IOD,
`RTIMAGE
`if RT Dose IOD,
`RTDOSE
`RTSTRUCT if RT Structure Set IOD,
`RTPLAN
`if RT Plan IOD.
`
`Note:
`
`DICOM specifies that a given series shall contain objects of only one Modality, and shall be created
`by a single device (described in the General Equipment Module). However, in general there may be
`many series defined for a given modality/device pair. Note that a radiotherapy series is generally
`created over an extended time interval (unlike in radiology, where all images in an image series are
`generally created together).
`
`Final Text, 4 June 1997
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`RT IODs
`
`C.8.X.2 RT Image Module
`Table C.8.X.2-1 contains attributes that describe RT-specific characteristics of a projection image. The
`image described by these attributes must be a radiotherapy image acquired or calculated using a conical
`imaging geometry.
`
`Table C.8.X.2-1—RT Image Module
`
`1
`
`1
`
`1
`
`Type Attribute Description
`1
`Number of samples (planes) in this
`image. See C.X.2.6.1 for specialization.
`Specifies the intended interpretation of
`the pixel data. See C.X.2.6.2 for
`specialization.
`Number of bits allocated for each pixel
`sample. Each sample shall have the
`same number of bits allocated. See
`C.X.2.6.3 for specialization.
`Number of bits stored for each pixel
`sample. Each sample shall have the
`same number of bits stored. See
`C.X.2.6.4 for specialization.
`Most significant bit for each pixel sample.
`Each sample shall have the same high
`bit. See C.X.2.6.5 for specialization.
`Data representation of the pixel samples.
`Each sample shall have the same pixel
`representation. See C.X.2.6.6 for
`specialization.
`User-defined label for RT Image.
`User-defined name for RT Image.
`User-defined description of RT Image.
`Name of operator(s) acquiring or
`creating RT Image.
`Image identification characteristics (see
`DICOM Part 3 Section C.7.6.1.1.2). RT
`Images shall use one of the following
`Defined Terms for Value 3:
`DRR = digitally reconstructed radiograph
`PORTAL = digital portal image or portal
`film image
`SIMULATOR = conventional simulator
`image
`RADIOGRAPH = radiographic image
`BLANK = image pixels set to background
`value
`Describes the kind of image conversion.
`Defined Terms:
`DV = Digitized Video
`DI = Digital Interface
`DF = Digitized Film
`WSD = Workstation
`
`Attribute Name
`Samples per Pixel
`
`Tag
`(0028,0002)
`
`Photometric Interpretation
`
`(0028,0004)
`
`Bits Allocated
`
`(0028,0100)
`
`Bits Stored
`
`(0028,0101)
`
`High Bit
`
`(0028,0102)
`
`Pixel Representation
`
`(0028,0103)
`
`RT Ima