Table C.8-18 specifies the Attributes that describe ultrasound images.
Table C.8-18. US Image Module Attributes
|
Attribute Name |
Tag |
Type |
Attribute Description |
|---|---|---|---|
|
Samples Per Pixel |
(0028,0002) |
1 |
Number of samples (planes) in this image. See Section C.8.5.6.1.12 for specialization |
|
Photometric Interpretation |
(0028,0004) |
1 |
Specifies the intended interpretation of the pixel data. See Section C.8.5.6.1.2 for specialization. |
|
Bits Allocated |
(0028,0100) |
1 |
Number of bits allocated for each pixel sample. See Section C.8.5.6.1.13 for specialization. |
|
Bits Stored |
(0028,0101) |
1 |
Number of bits stored for each pixel sample. See Section C.8.5.6.1.14 for specialization. |
|
High Bit |
(0028,0102) |
1 |
Most significant bit for pixel sample data. See Section C.8.5.6.1.15 for specialization. |
|
Planar Configuration |
(0028,0006) |
1C |
Indicates whether the pixel data are sent color-by-plane or color-by-pixel. Required if Samples per Pixel (0028,0002) has a value greater than 1. See Section C.8.5.6.1.16 for specialization. |
|
Pixel Representation |
(0028,0103) |
1 |
Data representation of pixel samples. See Section C.8.5.6.1.3 for specialization. |
|
Frame Increment Pointer |
(0028,0009) |
1C |
Contains the Data Element Tag of the attribute that is used as the frame increment in Multi-frame pixel data (see Section C.7.6.6). Required if Number of Frames is sent. See Section C.8.5.6.1.4 for specialization. |
|
Image Type |
(0008,0008) |
2 |
Image identification characteristics. See Section C.8.5.6.1.1 for specialization. |
|
Lossy Image Compression |
(0028,2110) |
1C |
Specifies whether an Image has undergone lossy compression (at a point in its lifetime). Enumerated Values:
Once this value has been set to 01 it shall not be reset. Required if Lossy Compression has been performed on the Image. May be present otherwise. |
|
Number of Stages |
(0008,2124) |
2C |
Number of Stages in this protocol. Required if image was acquired in a Staged protocol. |
|
Number of Views in Stage |
(0008,212A) |
2C |
Number of views in this Stage. Required if image was acquired in a Staged protocol. |
|
R Wave Time Vector |
(0018,6060) |
3 |
The time offset(s) of the reported R Wave peaks, each relative to the time of the start of the acquisition of the first frame in msec. Multi-valued, with one value per reported R Wave. |
|
Ultrasound Color Data Present |
(0028,0014) |
3 |
This element indicates if any ultrasound color data is present in an image. Enumerated Values:
|
|
Stage Name |
(0008,2120) |
3 |
A Stage is a particular time slice of a protocol in which a set of images are collected. The names can be free form text. Recommended text for Stress Echo stage names:
|
|
Stage Code Sequence |
(0040,000A) |
3 |
Sequence of items describing the performed Ultrasound Protocol Stage(s). One or more Items are permitted in this Sequence. |
|
Stage Number |
(0008,2122) |
3 |
A number that identifies the Stage. Stage Number starts at one. |
|
View Name |
(0008,2127) |
3 |
A View is a particular combination of the position and orientation when a set of images are acquired. Images are acquired at the same View in different Stages for the purpose of comparison. |
|
View Number |
(0008,2128) |
3 |
A number that identifies the View. View Number starts at one. |
|
Number of Event Timers |
(0008,2129) |
3 |
The number of event timers used at the time of acquisition of a Multi-frame image. |
|
Event Elapsed Time(s) |
(0008,2130) |
3 |
An array of values associated with each event timer. Units in milliseconds. |
|
Event Timer Name(s) |
(0008,2132) |
3 |
Name that identifies the event timer. |
|
Include Table 10-7 “General Anatomy Optional Macro Attributes” |
For intravascular ultrasound, Defined CID 3010 “Cardiovascular Anatomic Locations” and Defined CID 3015 “Coronary Arteries” are specified for the Anatomic Region Sequence and Defined CID 3019 “Cardiovascular Anatomic Location Modifiers” is specified for the Anatomic Region Modifier Sequence. No other Context IDs are specified. |
||
|
Include Table 10-25 “Optional View and Slice Progression Direction Attributes” |
See Section C.8.5.6.1.19 for Context Group IDs. |
||
|
Acquisition DateTime |
(0008,002A) |
1C |
The date and time that the acquisition of data that resulted in this image started. Required if Modality (0008,0060) = IVUS May be present otherwise. NoteThe synchronization of this time with an external clock is specified in the Synchronization Module in Acquisition Time Synchronized (0018,1800). |
|
Trigger Time |
(0018,1060) |
3 |
Time interval measured in msec from the start of the R-wave to the beginning of data taking |
|
Nominal Interval |
(0018,1062) |
3 |
Average R-R interval used for these data, in msec |
|
Beat Rejection Flag |
(0018,1080) |
3 |
Beat length sorting has been applied. Enumerated Values:
|
|
Low R-R Value |
(0018,1081) |
3 |
R-R interval low limit for beat rejection, in msec |
|
High R-R Value |
(0018,1082) |
3 |
R-R interval high limit for beat rejection, in msec |
|
Heart Rate |
(0018,1088) |
3 |
Beats per minute. |
|
IVUS Acquisition |
(0018,3100) |
1C |
Defined Terms:
Required if Modality (0008,0060) = IVUS |
|
IVUS Pullback Rate |
(0018,3101) |
1C |
Required if IVUS Acquisition (0018,3100) value is MOTOR_PULLBACK. Specified in units of mm/sec. |
|
IVUS Gated Rate |
(0018,3102) |
1C |
Required if IVUS Acquisition (0018,3100) value is GATED_PULLBACK. Specified in units of mm/beat. |
|
IVUS Pullback Start Frame Number |
(0018,3103) |
1C |
Required if IVUS Acquisition (0018,3100) value is MOTOR_PULLBACK or GATED_PULLBACK. |
|
IVUS Pullback Stop Frame Number |
(0018,3104) |
1C |
Required if IVUS Acquisition (0018,3100) value is MOTOR_PULLBACK or GATED_PULLBACK. |
|
Lesion Number |
(0018,3105) |
3 |
Identifier(s) of the lesion(s) of interest imaged within the current SOP Instance. Each lesion shall have a unique numeric integer identifier within the study. See Section C.8.5.6.1.26. |
|
Output Power |
(0018,5000) |
3 |
Manufacturer defined character string description of ultrasound output level(s) used in generating a given image. Data may be expressed in dB, %, W/cm2, etc. |
|
Transducer Data |
(0018,5010) |
3 |
Manufacturer defined code or description of ultrasound transducer used. |
|
Transducer Type |
(0018,6031) |
3 |
Defined Terms:
|
|
Focus Depth |
(0018,5012) |
3 |
The depth, from the transducer face, of the manufacturer defined beam focus used for the image, in cm. |
|
Processing Function |
(0018,5020) |
3 |
Manufacturer defined description of processing of echo information. Data may include code or description of gain (initial, overall, TGC, dynamic range, etc.), preprocessing, postprocessing, Doppler processing parameters, e.g., cutoff filters, etc., as used in generating a given image. |
|
Mechanical Index |
(0018,5022) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Bone Thermal Index |
(0018,5024) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Cranial Thermal Index |
(0018,5026) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Soft Tissue Thermal Index |
(0018,5027) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Soft Tissue-focus Thermal Index |
(0018,5028) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Soft Tissue-surface Thermal Index |
(0018,5029) |
3 |
See Section C.8.5.6.1.8 for Description. |
|
Depth of Scan Field |
(0018,5050) |
3 |
The depth, in mm, from the transducer face to the deepest point included in the displayed image- the field of view. |
|
Overlay Subtype |
(60xx,0045) |
3 |
Defined Term that identifies the intended purpose of the ROI Overlay Type. See Section C.8.5.6.1.11 for specialization. |
Referenced Overlay Sequence (0008,1130) and Referenced Curve Sequence (0008,1145) were previously included in this Module as optional Attributes but have been retired. See PS3.3-2004.
For US Images, Image Type (0008,0008) is specified to be Type 2.
Defined Terms for Value 3:
Value 4 is constructed as a modality bit map to allow for a description of multi-modality displays. In using this bit map, the sum of the values of the various modalities will unambiguously determine the constituent modalities.
Bit Map Values for Value 4:
2D Imaging
M-Mode
CW Doppler
PW Doppler
Color Doppler
Color M-Mode
3D Rendering
Color Power Mode
Tissue Characterization
Spatially-related frames
All Values are hexadecimal encoded as a CS. See PS3.5.
For example, Color Flow with CW spectral Doppler would have a value 4 = 0015. Note that no assumption should be made in Color Doppler or Color M-Mode regarding underlying B or M-Mode, respectively.
See Section A.59.1 for the relationship between a 3D volume set and the 3D Rendering, 3D MPR View, and Spatially-related frames image types. In the case of "3D Rendering", Derivation Code Sequence (0008,9215) should be used to describe the specific type of 3D rendering (volume rendering, surface rendering, multiplanar reformatting, etc.).
Defined Terms:
(retired)
It is recommended that future implementations should not use ARGB photometric interpretation.
See PS3.5 for restrictions imposed by compressed Transfer Syntaxes.
For US Images, Pixel Representation (0028,0103) is specified to use the following.
Enumerated Values:
unsigned integer
For US Multi-frame images, the Attribute Frame Increment Pointer (0028,0009) of the Multi-frame Module (see Section C.7.6.6) is specified by the following.
Defined Terms:
sequencing by Frame Time (0018,1063)
sequencing by Frame Time Vector (0018,1065)
The thermal and/or mechanical indices, when made available by a manufacturer, are defined according to the Standard for Real-Time Display of Thermal and Mechanical Acoustic Output Indices on Diagnostic Ultrasound Equipment, a voluntary performance standard jointly published by AIUM and NEMA.
This section was defined in a previous version of the DICOM Standard. The Section is now retired. See PS3.3-2003.
This data element can be used to indicate if an image contains any Ultrasound color data.
For example: Some Ultrasound images may have a Photometric Interpretation equal to RGB but the image will have no color information if R=G=B for all pixels.
For consistency within a particular implementation Monochrome Ultrasound images may be coded using a color photometric interpretation. In that case inclusion of this data element can significantly speed up processing. Since all components are known to be equal only one need be handled. The enhancements can be significant when compressed Transfer Syntaxes are used.
Defined Terms:
identification of the active area of a 2D/B-mode image
For US Images, Samples Per Pixel (0028,0002) is specified to use the following values for specific Photometric Interpretations:
Table C.8-19. US Samples Per Pixel
|
Photometric Interpretation |
Samples Per Pixel Value |
|---|---|
|
MONOCHROME2 |
1 |
|
RGB |
3 |
|
YBR_FULL |
3 |
|
YBR_FULL_422 |
3 |
|
YBR_PARTIAL_422 |
3 |
|
YBR_RCT |
3 |
|
YBR_ICT |
3 |
|
YBR_PARTIAL_420 |
3 |
|
PALETTE COLOR |
1 |
For US Images, Bits Allocated (0028,0100) is specified to use the following values for specific Photometric Interpretations:
Table C.8-20. US Bits Allocated
|
Photometric Interpretation |
Bits Allocated Value |
|---|---|
|
MONOCHROME2 |
8 |
|
RGB |
8 |
|
YBR_FULL |
8 |
|
YBR_FULL_422 |
8 |
|
YBR_PARTIAL_422 |
8 |
|
YBR_RCT |
8 |
|
YBR_ICT |
8 |
|
YBR_PARTIAL_420 |
8 |
|
PALETTE COLOR |
8 - 8 bit palette, or 16 - 16 bit palette |
For US Images, Bits Stored (0028,0101) shall be equal to Bits Allocated (0028,0100).
For US Images, High Bit (0028,0102) shall be one less than Bits Stored (0028,0101).
For US Images, Planar Configuration (0028,0006) is specified to use the following values for specific Photometric Interpretations:
Table C.8-23. US Planar Configuration
|
Photometric Interpretation |
Planar Configuration Value |
|---|---|
|
RGB |
0 - color-by-pixel, or 1 - color-by-plane |
|
YBR_FULL |
1 |
|
YBR_FULL_422 |
0 |
|
YBR_PARTIAL_422 |
0 |
|
YBR_RCT |
0 |
|
YBR_ICT |
0 |
|
YBR_PARTIAL_420 |
0 |
The view of the patient anatomy may be described using coded terminology in the View Code Sequence (0054,0220). The view is typically specified by transducer position relative to the patient anatomy and/or transducer orientation,
The view may be described by a single Code Sequence Item, or by combination of post-coordinated Code Sequence Items. The principal coded item is specified in View Code Sequence, and modifier terms in the View Modifier Code Sequence (0054,0222). The Baseline CIDs for post-coordinated encoding of view are:
CID 4 “Anatomic Region” (typically used for the primary coded item)
Any of these Context Groups may be used in either the View Code Sequence or the View Modifier Code Sequence.
For cardiac imaging, a Baseline CID with pre-coordinated view codes is specified:
Transducer Position Sequence (0008,2240) and Transducer Orientation Sequence (0008,2244), defined in this module in an earlier edition of the Standard (see PS3.3-2004), are retired.
Defined Terms:
The IVUS imaging catheter is positioned in the blood vessel under examination distal to the anatomical structures to be examined. Then the catheter is attached to a motorized mechanism capable of withdrawing the catheter through the vessel at a constant velocity specified by the attribute IVUS Pullback Rate (0018,3101) from the defined IVUS Pullback Start Frame Number (0018,3103) (see Section C.8.5.6.1.24) to the IVUS Pullback Stop Frame Number (0018,3104) (see Section C.8.5.6.1.25).
The IVUS imaging catheter is positioned in the blood vessel under examination distal to the anatomical structures to be examined. Then the catheter is manually withdrawn through the vessel region of interest.
The IVUS imaging catheter is positioned in the blood vessel under examination near the anatomical structures to be examined. Then the catheter is manually withdrawn or advanced through the vessel region of interest.
The IVUS imaging catheter is positioned in the blood vessel under examination distal to the anatomical structures to be examined. Then the catheter is attached to a motorized mechanism capable of withdrawing the catheter through the vessel at a rate specified by the attribute IVUS Gated Rate (0018,3102), once per heart cycle, from the defined IVUS Pullback Start Frame Number (0018,3103) (see Section C.8.5.6.1.24) to the IVUS Pullback Stop Frame Number (0018,3104) (see Section C.8.5.6.1.25).
The attribute IVUS Pullback Rate (0018,3101) is required when IVUS Acquisition (0018,3100) is MOTOR_PULLBACK and it specifies the velocity of withdrawal of the IVUS imaging catheter in millimeters per second.
The attribute IVUS Gated Rate (0018,3102) is required when IVUS Acquisition (0018,3100) is GATED_PULLBACK and it specifies the velocity of withdrawal of the IVUS imaging catheter in millimeters per beat.
The IVUS Pullback Start Frame Number (0018,3103) specifies the frame number of a IVUS multi-frame acquisition upon which motorized or gated pullback begins.
The IVUS Pullback Stop Frame Number (0018,3104) specifies the frame number of a IVUS multi-frame acquisition upon which motorized or gated pullback ends.
Attribute Lesion Number identifies the lesion(s) of interest imaged within the current SOP Instance. Each lesion shall have a unique numeric integer identifier within the study. If during a study the same lesion is imaged more than once, the same Lesion Number should be used for both SOP Instances.
Lesion Number is not a DICOM UID.
An IVUS pullback may contain multiple values in Lesion Number.