Computed Radiography ImageCIOD
Nuclear Medicine ImageCIOD
Ultrasound ImageCIOD
Ultrasound Multi-frame ImageCIOD
Secondary Capture ImageCIOD
Multi-frame Single Bit Secondary Capture ImageCIOD
Multi-frame Grayscale Byte Secondary Capture ImageCIOD
Multi-frame Grayscale Word Secondary Capture ImageCIOD
Multi-frame True Color Secondary Capture ImageCIOD
X-Ray Angiographic ImageCIOD
X-Ray Radiofluoroscopic ImageCIOD
RT Structure SetCIOD
Positron Emission Tomography ImageCIOD
Digital X-Ray ImageCIOD
Digital Mammography X-Ray ImageCIOD
Digital Intra-Oral X-Ray ImageCIOD
RT Beams Treatment RecordCIOD
RT Brachy Treatment RecordCIOD
RT Treatment Summary RecordCIOD
VL Endoscopic ImageCIOD
VL Microscopic ImageCIOD
VL Slide-Coordinates Microscopic ImageCIOD
VL Photographic ImageCIOD
Video Endoscopic ImageCIOD
Video Microscopic ImageCIOD
Video Photographic ImageCIOD
VL Whole Slide Microscopy ImageCIOD
Real-Time Video Endoscopic ImageCIOD
Real-Time Video Photographic ImageCIOD
Dermoscopic Photography ImageCIOD
Grayscale Softcopy Presentation StateCIOD
Color Softcopy Presentation StateCIOD
Pseudo-Color Softcopy Presentation StateCIOD
Blending Softcopy Presentation StateCIOD
Basic Structured DisplayCIOD
XA/XRF Grayscale Softcopy Presentation StateCIOD
Advanced Blending Presentation StateCIOD
Variable Modality LUT Softcopy Presentation StateCIOD
Basic Voice Audio WaveformCIOD
Ambulatory ECGCIOD
Hemodynamic WaveformCIOD
Basic Cardiac Electrophysiology WaveformCIOD
Arterial Pulse WaveformCIOD
Respiratory WaveformCIOD
General Audio WaveformCIOD
Real-Time Audio WaveformCIOD
Routine Scalp ElectroencephalogramCIOD
Sleep ElectroencephalogramCIOD
Multi-channel Respiratory WaveformCIOD
Body Position WaveformCIOD
General 32-bit ECGCIOD
Basic Text SRCIOD
Enhanced SRCIOD
Comprehensive SRCIOD
Key Object Selection DocumentCIOD
Mammography CAD SRCIOD
Procedure LogCIOD
X-Ray Radiation Dose SRCIOD
Spectacle Prescription ReportCIOD
Macular Grid Thickness and Volume ReportCIOD
Implantation Plan SR DocumentCIOD
Comprehensive 3D SRCIOD
Radiopharmaceutical Radiation Dose SRCIOD
PatientMModule - Patient
Clinical Trial SubjectUModule - Patient
General StudyMModule - Study
Patient StudyUModule - Study
Clinical Trial StudyUModule - Study
SR Document SeriesMModule - Series
Clinical Trial SeriesUModule - Series
SynchronizationCModule - Frame of Reference
General EquipmentMModule - Equipment
Enhanced General EquipmentMModule - Equipment
SR Document GeneralMModule - SR Document
SR Document ContentMModule - SR Document
(0008,1199) Referenced SOP Sequence1Sequence
(0040,A032) Observation DateTime1CDate Time
(0040,A040) Value Type1Code String
(0040,A043) Concept Name Code Sequence1CSequence
(0040,A050) Continuity Of Content1Code String
(0040,A120) DateTime1CDate Time
(0040,A121) Date1CDate
(0040,A122) Time1CTime
(0040,A123) Person Name1CPerson Name
(0040,A124) UID1CUnique Identifier
(0040,A130) Temporal Range Type1Code String
(0040,A132) Referenced Sample Positions1CUnsigned Long
(0040,A138) Referenced Time Offsets1CDecimal String
(0040,A13A) Referenced DateTime1CDate Time
(0040,A160) Text Value1CUnlimited Text
(0040,A168) Concept Code Sequence1Sequence
(0040,A171) Observation UID3Unique Identifier
(0040,A300) Measured Value Sequence2Sequence
(0040,A301) Numeric Value Qualifier Code Sequence1CSequence
(0040,A504) Content Template Sequence1CSequence
(0040,A730) Content Sequence1CSequence
(0040,A801) Tabulated Values Sequence1Sequence
(0048,0301) Pixel Origin Interpretation1CCode String
(0070,0022) Graphic Data1Single
(0070,0023) Graphic Type1Code String
(0070,031A) Fiducial UID3Unique Identifier
(3006,0024) Referenced Frame of Reference UID1Unique Identifier
SOP CommonMModule - SR Document
Extensible SRCIOD
Acquisition Context SRCIOD
Simplified Adult Echo SRCIOD
Patient Radiation Dose SRCIOD
Planned Imaging Agent Administration SRCIOD
Performed Imaging Agent Administration SRCIOD
Rendition Selection DocumentCIOD
Enhanced X-Ray Radiation Dose SRCIOD
Enhanced MR ImageCIOD
MR SpectroscopyCIOD
Enhanced MR Color ImageCIOD
Raw DataCIOD
Enhanced CT ImageCIOD
Spatial RegistrationCIOD
Deformable Spatial RegistrationCIOD
Spatial FiducialsCIOD
Ophthalmic Photography 8 Bit ImageCIOD
Ophthalmic Photography 16 Bit ImageCIOD
Stereometric RelationshipCIOD
Hanging ProtocolCIOD
Encapsulated PDFCIOD
Encapsulated CDACIOD
Real World Value MappingCIOD
Enhanced XA ImageCIOD
Enhanced XRF ImageCIOD
RT Ion Beams Treatment RecordCIOD
Ophthalmic Tomography ImageCIOD
X-Ray 3D Angiographic ImageCIOD
X-Ray 3D Craniofacial ImageCIOD
Breast Tomosynthesis ImageCIOD
Enhanced PET ImageCIOD
Surface SegmentationCIOD
Color PaletteCIOD
Enhanced US VolumeCIOD
Lensometry MeasurementsCIOD
Autorefraction MeasurementsCIOD
Keratometry MeasurementsCIOD
Subjective Refraction MeasurementsCIOD
Visual Acuity MeasurementsCIOD
Ophthalmic Axial MeasurementsCIOD
Intraocular Lens CalculationsCIOD
Generic Implant TemplateCIOD
Implant Assembly TemplateCIOD
Implant Template GroupCIOD
RT Beams Delivery InstructionCIOD
Ophthalmic Visual Field Static Perimetry MeasurementsCIOD
Intravascular Optical Coherence Tomography ImageCIOD
Ophthalmic Thickness MapCIOD
Surface Scan MeshCIOD
Surface Scan Point CloudCIOD
Legacy Converted Enhanced CT ImageCIOD
Legacy Converted Enhanced MR ImageCIOD
Legacy Converted Enhanced PET ImageCIOD
Corneal Topography MapCIOD
Breast Projection X-Ray ImageCIOD
Parametric MapCIOD
Wide Field Ophthalmic Photography Stereographic Projection ImageCIOD
Wide Field Ophthalmic Photography 3D Coordinates ImageCIOD
Tractography ResultsCIOD
RT Brachy Application Setup Delivery InstructionCIOD
Planar MPR Volumetric Presentation StateCIOD
Volume Rendering Volumetric Presentation StateCIOD
Content Assessment ResultsCIOD
CT Performed Procedure ProtocolCIOD
CT Defined Procedure ProtocolCIOD
Protocol ApprovalCIOD
XA Performed Procedure ProtocolCIOD
XA Defined Procedure ProtocolCIOD
Ophthalmic Optical Coherence Tomography En Face ImageCIOD
Ophthalmic Optical Coherence Tomography B-scan Volume AnalysisCIOD
Encapsulated STLCIOD
Encapsulated OBJCIOD
Encapsulated MTLCIOD
RT Physician IntentCIOD
RT Segment AnnotationCIOD
RT Radiation SetCIOD
C-Arm Photon-Electron RadiationCIOD
Tomotherapeutic RadiationCIOD
Robotic-Arm RadiationCIOD
RT Radiation Record SetCIOD
RT Radiation Salvage RecordCIOD
C-Arm Photon-Electron Radiation RecordCIOD
Tomotherapeutic Radiation RecordCIOD
Robotic-Arm Radiation RecordCIOD
RT Radiation Set Delivery InstructionCIOD
RT Treatment PreparationCIOD
Enhanced RT ImageCIOD
Enhanced Continuous RT ImageCIOD
RT Patient Position Acquisition InstructionCIOD
Microscopy Bulk Simple AnnotationsCIOD
Photoacoustic ImageCIOD
Confocal Microscopy ImageCIOD
Confocal Microscopy Tiled Pyramidal ImageCIOD
Basic DirectoryCIOD

Built with by Innolitics, a team of medical imaging software developers.

Data synced with official DICOM standard on 18 April 2024. The DICOM Standard is under continuous maintenance, and the current official version is available at DICOM Parts 3, 4, and 6, © NEMA. Please note that the most recent PDF version of the standard is the official reference, and should checked when making technical decisions.

Referenced Frame of Reference UID Attribute

TypeRequired (1)
Value Multiplicity1
Value RepresentationUnique Identifier (UI)
Example Values

Uniquely identifies the Frame of Reference within which the coordinates are defined.


  1. There is no requirement that the Frame of Reference be the same for all SCOORD3D Content Items in the same SR SOP Instance, nor is there any requirement that the Frame of Reference Module be present.

  2. The Frame of Reference may be any type of DICOM Reference Coordinate System, whether it be patient-relative (Patient Based Coordinate System), volume-relative (including acquired and presentation state volumes), or whole slide relative (Slide Coordinate System).

Frame of Reference Module

C.7.4.1 Frame of Reference Module

Table C.7-6 specifies the Attributes of the Frame of Reference Module, which are necessary to uniquely identify a Frame of Reference that ensures the spatial relationship of Images within a Series. It also allows Images across multiple Series to share the same Frame of Reference. This Frame of Reference (or coordinate system) shall be constant for all Images related to a specific Frame of Reference.

When a Frame of Reference is identified, it is not important how the imaging target (patient, specimen, or phantom) is positioned relative to the imaging equipment or where the origin of the Frame of Reference is located. It is important that the position of the imaging target and the origin are constant in relationship to a specific Frame of Reference.


Since the criteria used to group images into a Series is application specific, it is possible for imaging applications to define multiple Series within a Study that share the same imaging space. Previous versions of the DICOM Standard specified that all images within the Series must be spatially related. However, insufficient information was available to determine if multiple Series within a Study were spatially related.

Table C.7-6. Frame of Reference Module Attributes

Attribute Name



Attribute Description

Frame of Reference UID



Uniquely identifies the Frame of Reference for a Series. See Section C. for further explanation.

Position Reference Indicator



Part of the imaging target used as a reference. See Section C. for further explanation.

C. Frame of Reference Module Attribute Descriptions
C. Frame of Reference UID

The Frame of Reference UID (0020,0052) shall be used to uniquely identify a Frame of Reference for a Series. Each Series shall have a single Frame of Reference UID. However, multiple Series within a Study may share a Frame of Reference UID. All images in a Series that share the same Frame of Reference UID shall be spatially related to each other.


  1. Previous versions of this Standard defined a Data Element "Location", which has been retired. Frame of Reference UID provides a completely unambiguous identification of the image location reference used to indicate position.

  2. A common Frame of Reference UID may be used to spatially relate localizer images with a set of transverse images. However, in some cases (e.g., multiple localizer images being related to a single set of transverse images) a common Frame of Reference UID may not be sufficient. The Referenced Image Sequence (0008,1140) provides an unambiguous method for relating localizer images.

C. Position Reference Indicator

The Position Reference Indicator (0020,1040) specifies the part of the imaging target that was used as a reference point associated with a specific Frame of Reference UID. The Position Reference Indicator may or may not coincide with the origin of the fixed Frame of Reference related to the Frame of Reference UID.

For a Patient-related Frame of Reference, this is an anatomical reference point such as the iliac crest, orbital-medial, sternal notch, symphysis pubis, xiphoid, lower costal margin, or external auditory meatus, or a fiducial marker placed on the patient. The Patient-Based Coordinate System is described in Section C.

For a slide-related Frame of Reference, this is the slide corner as specified in Section C. and shall be identified in this Attribute with the value "SLIDE_CORNER". The slide-based coordinate system is described in Section C.

For an Ophthalmic Coordinate System, the Frame of Reference is based upon the corneal vertex. The corneal vertex is determined by the measuring instrument and shall be identified in this Attribute with the value CORNEAL_VERTEX_R (for the right eye) or CORNEAL_VERTEX_L (for the left eye). The Ophthalmic Coordinate System is described in Section C.

The Position Reference Indicator shall be used only for annotation purposes and is not intended to be used as a mathematical spatial reference.


The Position Reference Indicator may be encoded as zero length when it has no meaning, for example, when the Frame of Reference Module is required to relate mammographic images of the breast acquired without releasing breast compression, but where there is no meaningful anatomical reference point as such.