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
PatientMModule - Patient
Clinical Trial SubjectUModule - Patient
General StudyMModule - Study
Patient StudyUModule - Study
Clinical Trial StudyUModule - Study
RT SeriesMModule - Series
Clinical Trial SeriesUModule - Series
Frame of ReferenceUModule - Frame of Reference
General EquipmentMModule - Equipment
RT General PlanMModule - Plan
RT PrescriptionUModule - Plan
RT Tolerance TablesUModule - Plan
RT Patient SetupUModule - Plan
RT Fraction SchemeUModule - Plan
RT BeamsCModule - Plan
(300A,00B0) Beam Sequence1Sequence
(0008,0070) Manufacturer3Long String
(0008,0080) Institution Name3Long String
(0008,0081) Institution Address3Short Text
(0008,1040) Institutional Department Name3Long String
(0008,1041) Institutional Department Type Code Sequence3Sequence
(0008,1090) Manufacturer's Model Name3Long String
(0008,1156) Definition Source Sequence3Sequence
(0018,1000) Device Serial Number3Long String
(0018,1204) Date of Manufacture3Date
(0018,1205) Date of Installation3Date
(3002,0050) Primary Fluence Mode Sequence3Sequence
(3008,00A1) Enhanced RT Beam Limiting Device Sequence1CSequence
(3008,00A3) Enhanced RT Beam Limiting Device Definition Flag3Code String
(300A,00B2) Treatment Machine Name2Short String
(300A,00B3) Primary Dosimeter Unit3Code String
(300A,00B4) Source-Axis Distance3Decimal String
(300A,00B6) Beam Limiting Device Sequence1CSequence
(300A,00C0) Beam Number1Integer String
(300A,00C2) Beam Name3Long String
(300A,00C3) Beam Description3Short Text
(300A,00C4) Beam Type1Code String
(300A,00C6) Radiation Type2Code String
(300A,00C7) High-Dose Technique Type1CCode String
(300A,00CA) Planned Verification Image Sequence3Sequence
(300A,00CE) Treatment Delivery Type3Code String
(300A,00D0) Number of Wedges1Integer String
(300A,00D1) Wedge Sequence1CSequence
(300A,00E0) Number of Compensators1Integer String
(300A,00E2) Total Compensator Tray Factor3Decimal String
(300A,00E3) Compensator Sequence1CSequence
(300A,00ED) Number of Boli1Integer String
(300A,00F0) Number of Blocks1Integer String
(300A,00F2) Total Block Tray Factor3Decimal String
(300A,00F4) Block Sequence1CSequence
(300A,0107) Applicator Sequence3Sequence
(300A,010E) Final Cumulative Meterset Weight1CDecimal String
(300A,0110) Number of Control Points1Integer String
(300A,0111) Control Point Sequence1Sequence
(3008,00A2) Enhanced RT Beam Limiting Opening Sequence2CSequence
(300A,0112) Control Point Index1Integer String
(300A,0114) Nominal Beam Energy3Decimal String
(300A,0115) Dose Rate Set3Decimal String
(300A,0116) Wedge Position Sequence1CSequence
(300A,011A) Beam Limiting Device Position Sequence1CSequence
(300A,011E) Gantry Angle1CDecimal String
(300A,011F) Gantry Rotation Direction1CCode String
(300A,0120) Beam Limiting Device Angle1CDecimal String
(300A,0121) Beam Limiting Device Rotation Direction1CCode String
(300A,0122) Patient Support Angle1CDecimal String
(300A,0123) Patient Support Rotation Direction1CCode String
(300A,0124) Table Top Eccentric Axis Distance3Decimal String
(300A,0125) Table Top Eccentric Angle1CDecimal String
(300A,0126) Table Top Eccentric Rotation Direction1CCode String
(300A,0128) Table Top Vertical Position2CDecimal String
(300A,0129) Table Top Longitudinal Position2CDecimal String
(300A,012A) Table Top Lateral Position2CDecimal String
(300A,012C) Isocenter Position2CDecimal String
(300A,012E) Surface Entry Point3Decimal String
(300A,0130) Source to Surface Distance3Decimal String
(300A,0132) Source to External Contour Distance3Single
(300A,0133) External Contour Entry Point3Single
(300A,0134) Cumulative Meterset Weight2Decimal String
(300A,0140) Table Top Pitch Angle1CSingle
(300A,0142) Table Top Pitch Rotation Direction1CCode String
(300A,0144) Table Top Roll Angle1CSingle
(300A,0146) Table Top Roll Rotation Direction1CCode String
(300A,014A) Gantry Pitch Angle3Single
(300A,014C) Gantry Pitch Rotation Direction3Code String
(300C,0050) Referenced Dose Reference Sequence3Sequence
(300C,0080) Referenced Dose Sequence1CSequence
(300A,0420) General Accessory Sequence3Sequence
(300C,0042) Referenced Reference Image Sequence3Sequence
(300C,0050) Referenced Dose Reference Sequence3Sequence
(300C,006A) Referenced Patient Setup Number3Integer String
(300C,0080) Referenced Dose Sequence3Sequence
(300C,00A0) Referenced Tolerance Table Number3Integer String
(300C,00B0) Referenced Bolus Sequence1CSequence
(3010,0038) Entity Long Label3Long String
RT Brachy Application SetupsCModule - Plan
ApprovalUModule - Plan
General ReferenceUModule - Plan
SOP CommonMModule - Plan
Common Instance ReferenceUModule - Plan
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
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.

External Contour Entry Point Attribute

TypeOptional (3)
Value Multiplicity3
Value RepresentationSingle (FL)

External Contour entry point coordinates (x,y,z) in the Patient-Based Coordinate System described in Section C. (mm).

See Section C.

Section C.

C. Image Position and Image Orientation

Image Position (Patient) (0020,0032) specifies the x, y, and z coordinates of the upper left hand corner of the image; it is the center of the first voxel transmitted. Image Orientation (Patient) (0020,0037) specifies the direction cosines of the first row and the first column with respect to the patient. These Attributes shall be provide as a pair. Row value for the x, y, and z axes respectively followed by the Column value for the x, y, and z axes respectively.

The direction of the axes is defined fully by the patient's orientation.

If Anatomical Orientation Type (0010,2210) is absent or has a value of BIPED, the x-axis is increasing to the left hand side of the patient. The y-axis is increasing to the posterior side of the patient. The z-axis is increasing toward the head of the patient.

If Anatomical Orientation Type (0010,2210) has a value of QUADRUPED, the

  • x-axis is increasing to the left (as opposed to right) side of the patient

  • the y-axis is increasing towards

    • the dorsal (as opposed to ventral) side of the patient for the neck, trunk and tail,

    • the dorsal (as opposed to ventral) side of the patient for the head,

    • the dorsal (as opposed to plantar or palmar) side of the distal limbs,

    • the cranial (as opposed caudal) side of the proximal limbs, and

  • the z-axis is increasing towards

    • the cranial (as opposed to caudal) end of the patient for the neck, trunk and tail,

    • the rostral (as opposed to caudal) end of the patient for the head, and

    • the proximal (as opposed to distal) end of the limbs


  1. The axes for quadrupeds are those defined and illustrated in Smallwood et al for proper anatomic directional terms as they apply to various parts of the body.

  2. It should be anticipated that when quadrupeds are imaged on human equipment, and particularly when they are position in a manner different from the traditional human prone and supine head or feet first longitudinal position, then the equipment may well not indicate the correct orientation, though it will remain an orthogonal Cartesian right-handed system that could be corrected subsequently.

The Patient-Based Coordinate System is a right handed system, i.e., the vector cross product of a unit vector along the positive x-axis and a unit vector along the positive y-axis is equal to a unit vector along the positive z-axis.


If a patient is positioned parallel to the ground, in dorsal recumbency (i.e., for humans, face-up on the table), with the caudo-cranial (i.e., for humans, feet-to-head) direction the same as the front-to-back direction of the imaging equipment, the direction of the axes of this Patient-Based Coordinate System and the Equipment-Based Coordinate System in previous versions of this Standard will coincide.

The Image Plane Attributes, in conjunction with the Pixel Spacing Attribute, describe the position and orientation of the image slices relative to the Patient-Based Coordinate System. In each image frame Image Position (Patient) (0020,0032) specifies the origin of the image with respect to the Patient-Based Coordinate System. RCS and Image Orientation (Patient) (0020,0037) values specify the orientation of the image frame rows and columns. The mapping of an integer (entire) pixel location (i,j) to the RCS is calculated as follows:

Equation C. 


  • Pxyz The coordinates of the voxel (i,j) in the frame's image plane in units of mm.

  • Sxyz The three values of Image Position (Patient) (0020,0032). It is the location in mm from the origin of the RCS.

  • Xxyz The values from the row (X) direction cosine of Image Orientation (Patient) (0020,0037).

  • Yxyz The values from the column (Y) direction cosine of Image Orientation (Patient) (0020,0037).

  • i Column integer index to the image plane. The first (entire) column is index zero.

  • Δi Column pixel resolution of Pixel Spacing (0028,0030) in units of mm.

  • j Row integer index to the image plane. The first (entire) row index is zero.

  • Δj Row pixel resolution of Pixel Spacing (0028,0030) in units of mm.


The integer entire row and column indices (i,j) that are the input to this equation start from zero, which is a common mathematical convention. Many DICOM Attributes define such indices as starting from one, e.g., those affected by Bounding Box Annotation Units (0070,0003) for PIXEL and MATRIX in Section C.10.5 Graphic Annotation Module. This needs to be accounted for when applying this equation literally.

The mapping of a sub-pixel resolution image or total pixel matrix relative location (c,r), such as used in Spatial Coordinates Macro, to the RCS is calculated as follows

Equation C. 


  • Pxyz The coordinates of the voxel (c,r) in the frame's image plane in units of mm.

  • Sxyz The three values of Image Position (Patient) (0020,0032). It is the location in mm from the origin of the RCS.

  • Xxyz The values from the row (X) direction cosine of Image Orientation (Patient) (0020,0037).

  • Yxyz The values from the column (Y) direction cosine of Image Orientation (Patient) (0020,0037).

  • c Column sub-pixel resolution index to the image plane. The left pixel edge of the first column of the frame or total pixel matrix is index zero.

  • Δc Column pixel resolution of Pixel Spacing (0028,0030) in units of mm.

  • r Row sub-pixel resolution index to the image plane. The top pixel edge of the first row of the frame or total pixel matrix index is zero.

  • Δr Row pixel resolution of Pixel Spacing (0028,0030) in units of mm.

Additional constraints apply:

  1. The row and column direction cosine vectors shall be orthogonal, i.e., their dot product shall be zero.

  2. The row and column direction cosine vectors shall be normal, i.e., the dot product of each direction cosine vector with itself shall be unity.

Section C.

C. Source to External Contour Distance and External Contour Entry Point

The Source to External Contour Distance (300A,0132) is the distance to the beam entry point (External Contour Entry Point), which may include Bolus, Patient Positioning Devices, Patient Immobilization Devices or other devices. This value is useful for including the attenuation effects of external devices on the dose calculation and for patient setup.