DICOM PS3.3 2024b - Information Object Definitions

C.8.34 Photoacoustic Modules

C.8.34.1 Photoacoustic Image

This section describes the Photoacoustic Image Module.

Table C.8.34.1-1 contains the Attributes that describe Photoacoustic Images.

Table C.8.34.1-1. Photoacoustic Image Module Attributes

Attribute Name

Tag

Type

Attribute Description

Image Type

(0008,0008)

1

Image characteristics. See Section C.8.34.1.1 for specialization.

Dimension Organization Type

(0020,9311)

1

Dimension organization of the Instance.

Defined Terms:

3D

Spatial Multi-frame image of equally spaced parallel planes (3D volume set).

3D_TEMPORAL

Temporal loop of equally spaced parallel-plane 3D volume sets.

See Section C.8.34.1.2 for details.

Acquisition DateTime

(0008,002A)

1

The date and time that the acquisition of data that resulted in this image started.

Include Table C.8-131 “Common CT/MR and Photoacoustic Image Description Macro Attributes”

Samples per Pixel

(0028,0002)

1

Number of samples (planes) in this image. For Enumerated Values See Section C.8.34.1.3.

Photometric Interpretation

(0028,0004)

1

Specifies the intended interpretation of the pixel data. Enumerated Values are specified in the IOD that invokes this Module. See Section C.7.6.3.1.2 for definition of this term.

Bits Allocated

(0028,0100)

1

Number of bits allocated for each pixel sample. Each sample shall have the same number of bits allocated. For Enumerated Values See Section C.8.34.1.3.

Bits Stored

(0028,0101)

1

Number of bits stored for each pixel sample. Each sample shall have the same number of bits stored. For Enumerated Values See Section C.8.34.1.3.

High Bit

(0028,0102)

1

Most significant bit for pixel sample data. Each sample shall have the same high bit. Shall be one less than the value in Bits Stored (0028,0101).

Pixel Representation

(0028,0103)

1

Data representation of the pixel samples. Each sample shall have the same pixel representation. For Enumerated Values see Section C.8.34.1.3.

Planar Configuration

(0028,0006)

1C

Indicates whether the pixel data are encoded color-by-plane or color-by-pixel. Required if Samples per Pixel (0028,0002) has a value greater than 1. See Section C.7.6.3.1.3 and Section C.8.34.1.3 for further explanation.

Position Measuring Device Used

(0018,980C)

1

Describes the type of position measuring device used in the acquisition of the image. This gives an indication of the degree of precision of Pixel Spacing (0028,0030) and the spacing between adjacent planes.

Note

The actual precision will depend on a variety of factors such as the tracking technology used and the quality of the calibration.

Enumerated Values:

RIGID

The image was acquired with a position measuring device that rigidly connects the transducer to a frame of reference.

TRACKED

The image was acquired using freehand motion of the transducer with an associated position measuring device (i.e., tracked freehand transducer).

FREEHAND

The image was acquired using freehand motion of the transducer without a position measuring device.

Lossy Image Compression

(0028,2110)

1

Specifies whether an Image has undergone lossy compression (at a point in its lifetime).

Enumerated Values:

00

Image has not been subjected to lossy compression.

01

Image has been subjected to lossy compression.

Once this value has been set to "01" it shall not be reset.

See Section C.7.6.1.1.5.

Lossy Image Compression Ratio

(0028,2112)

1C

Describes the approximate lossy compression ratio(s) that have been applied to this image.

See Section C.7.6.1.1.5.2.

Required if Lossy Image Compression (0028,2110) is "01".

Lossy Image Compression Method

(0028,2114)

1C

A label for the lossy compression method(s) that have been applied to this image.

See Section C.7.6.1.1.5.1.

Required if Lossy Image Compression (0028,2110) is "01".

Presentation LUT Shape

(2050,0020)

1C

Specifies an identity transformation for the Presentation LUT, such that the output of all grayscale transformations defined in the IOD containing this Module are defined to be P-Values.

Enumerated Values:

IDENTITY

output is in P-Values.

Required if Photometric Interpretation (0028,0004) is MONOCHROME2.

Burned In Annotation

(0028,0301)

1

Indicates whether or not image contains sufficient burned in annotation to identify the patient and date the image was acquired.

Enumerated Values:

NO

Recognizable Visual Features

(0028,0302)

3

Indicates whether or not the image contains sufficiently recognizable visual features to allow the image or a reconstruction from a set of images to identify the patient.

Enumerated Values:

YES

NO

If this Attribute is absent, then the image may or may not contain recognizable visual features.

Icon Image Sequence

(0088,0200)

3

This icon image is representative of the image.

Only a single Item is permitted in this Sequence.

>Include Table C.7-11b “Image Pixel Macro Attributes”

See Section C.7.6.1.1.6.


C.8.34.1.1 Photoacoustic Image Type
C.8.34.1.1.1 Pixel Data Characteristics

Value 1 of Image Type (0008,0008) and Frame Type (0008,9007) is discussed in Section C.8.16.1.1.

C.8.34.1.1.2 Patient Examination Characteristics

Value 2 of Image Type (0008,0008) and Frame Type (0008,9007) is discussed in Section C.8.16.1.2.

C.8.34.1.1.3 Image Flavor

See Section C.8.16.1.3 for requirements, but not Defined Terms.

Table C.8.34.1.1.3-1 specifies the Defined Terms for Photoacoustic Images for Value 3 for Image Type (0008,0008) and Frame Type (0008,9007).

Table C.8.34.1.1.3-1. Photoacoustic Image Type and Frame Type Value 3

Defined Term Name

Defined Term Description

VOLUME

Set of frames that define a regularly sampled volume

NON_PARALLEL

Set of frames that are not parallel

PARALLEL

Set of frames that are parallel but do not constitute a regularly sampled volume


C.8.34.1.1.4 Derived Pixel Contrast

Value 4 of Image Type (0008,0008) and Frame Type (0008,9007) is discussed in Section C.8.16.1.4.

C.8.34.1.2 Photoacoustic Dimension Organization Type

Photoacoustic Image studies include one or more Photoacoustic images indexed with Multi-frame Dimensions. The Dimension Organization Type (0020,9311) specifies the general structure of the image. The concept of "multi-frame dimensions" as specified by the Dimension Index Sequence (0020,9222) and per-frame Dimension Index Values (0020,9157) is used to specify the relationships of frames within that general structure.

The Dimension Index Sequence (0020,9222) shall have at least three Items, with the dimension values described in Table C.8.34.1.2-1. I.e., these Dimension values will all be present even if there is only one value for a given Dimension.

Note

It is expected that some implementations may include additional dimensions such as Photoacoustic Excitation Characteristics Sequence (0018,9821) or Reconstruction Algorithm Sequence (0018,993D).

Table C.8.34.1.2-1. Dimension Definition for PA Images

Item

Attribute

Tag

Value

Dimension Index Sequence

(0020,9222)

1st

>Dimension Index Pointer

(0020,9165)

Temporal Position Time Offset (0020,930d)

>Functional Group Pointer

(0020,9167)

Temporal Position Sequence (0020,9310)

...

2nd

>Dimension Index Pointer

(0020,9165)

Image Position (Volume) (0020,9301)

>Functional Group Pointer

(0020,9167)

Plane Position (Volume) Sequence (0020,930E)

...

3rd

>Dimension Index Pointer

(0020,9165)

Image Data Type Sequence (0018,9807)

...


C.8.34.1.3 Photometric Interpretation, Pixel Representation, Samples Per Pixel, Planar Configuration, Bits Allocated and Bits Stored

Table C.8.34.1.3-1 specifies the Enumerated Values and allowed combinations of Samples per Pixel (0028,0002), Planar Configuration (0028,0006), Pixel Representation (0028,0103), Bits Allocated (0028,0100) and Bits Stored (0028,0101) for each Photometric Interpretation allowed by the IOD that invokes this Module.

Table C.8.34.1.3-1. Allowed Combinations of Attribute Values for Photometric Interpretation, Samples Per Pixel, Planar Configuration, Pixel Representation, Bits Allocated and Bits Stored

Photometric Interpretation

Samples per Pixel

Planar Configuration

Pixel Representation

Bits Allocated

Bits Stored

MONOCHROME2

1

-

0

8

8

MONOCHROME2

1

-

0

16

16

RGB

3

0

0

8

8

YBR_ICT

3

0

0

8

8

YBR_RCT

3

0

0

8

8

YBR_PARTIAL_420

3

0

0

8

8

YBR_FULL_422

3

0

0

8

8

YBR_FULL

3

0

0

8

8


DICOM PS3.3 2024b - Information Object Definitions