DICOM PS3.3 2019c - Information Object Definitions

C.34.12 Performed CT Reconstruction Module

This Module contains reconstruction parameter values for a performed CT imaging procedure.

This Module contains Attributes that affect machine behavior but not those that are merely descriptive. The latter may be found in the reconstructed images.

Table  C.34.12-1. Performed CT Reconstruction Module Attributes

Attribute Name

Tag

Type

Attribute Description

Reconstruction Protocol Element Sequence

(0018,9934)

1

Parameter values for each reconstruction protocol element in the Protocol. See Section C.34.11.1. Elements are performed in the order of their Protocol Element Number (0018,9921).

One or more Items shall be included in this Sequence.

>Include Table 10.28-1 “Protocol Element Identification Macro Attributes”

>Source Acquisition Protocol Element Number

(0018,9938)

1

A value corresponding to the Protocol Element Number (0018,9921) of the Acquisition Protocol Element from this Protocol being reconstructed in this reconstruction protocol element.

This may be multi-valued if multiple acquisitions are combined in a single reconstruction protocol element.

>Source Acquisition Beam Number

(0018,9939)

1

One or more values corresponding to the Beam Number (300A,00C0) in the Acquisition Protocol Element (specified in Source Acquisition Protocol Element Number (0018,9938) ) from which data was used in this reconstruction protocol element.

>Referenced SOP Class UID

(0008,1150)

1C

Uniquely identifies the referenced SOP Class.

Required if the referenced acquisition protocol element is not in this instance.

Shall have a value of 1.2.840.10008.5.1.4.1.1.200.2 (CT Performed Procedure Protocol Storage).

>Referenced SOP Instance UID

(0008,1155)

1C

The UID of the instance containing the acquisition protocol element referenced in Source Acquisition Protocol Element Number (0018,9938).

Required if the referenced acquisition protocol element is not in this instance.

>Reconstruction Start Location Sequence

(0018,993B)

1

Anatomically oriented transverse location where this reconstruction starts.

Note

  1. This represents the start of the data used in the reconstruction, not necessarily the slice location of the first reconstructed slice.

  2. This represents the intended start location. The operator may or may not have selected a location that exactly matches this anatomical location.

  3. In the case where an anatomical reference basis cannot be determined or derived from the Defined Protocol instance, for example when an ad hoc reconstruction is being performed, the implementation may use the acquired volume (128160, DCM, "Acquired Volume") as the reference basis with an appropriate offset.

Only a single Item is permitted in the Sequence.

>>Include Table 10.27-1 “Reference Location Macro Attributes”

BCID 1000 “CT Transverse Plane Reference Basis” for Reference Basis Code Sequence (0018,9902)

BCID 1010 “Reference Geometry - Planes” for Reference Geometry Code Sequence (0018,9903)

>Reconstruction End Location Sequence

(0018,993C)

1

Anatomically oriented transverse location where this reconstruction ends.

Note

  1. This represents the end of the data used in the reconstruction, not necessarily the slice location of the last reconstructed slice.

  2. This represents the intended end location. The operator may or may not have selected a location that exactly matches this anatomical location.

  3. In the case where an anatomical reference basis cannot be determined or borrowed from the Defined Protocol instance, for example when an ad hoc reconstruction is being performed, the implementation may use the acquired volume (128160, DCM, "Acquired Volume") as the reference basis with an appropriate offset.

Only a single Item is permitted in the Sequence.

>>Include Table 10.27-1 “Reference Location Macro Attributes”

BCID 1000 “CT Transverse Plane Reference Basis” for Reference Basis Code Sequence (0018,9902)

BCID 1010 “Reference Geometry - Planes” for Reference Geometry Code Sequence (0018,9903)

>Reconstruction Algorithm Sequence

(0018,993D)

3

Algorithm used in this reconstruction protocol element.

Only a single Item is permitted in the Sequence.

>>Include Table 10-19 “Algorithm Identification Macro Attributes”

BCID 10033 “CT Reconstruction Algorithm” for Algorithm Family Code Sequence (0066,002F)

>Convolution Kernel

(0018,1210)

1

A label describing the convolution kernel or algorithm used to reconstruct the data.

A single value shall be present.

>Convolution Kernel Group

(0018,9316)

1

A label describing the group that the Convolution Kernel (0018,1210) belongs.

Defined Terms:

BRAIN

SOFT_TISSUE

LUNG

BONE

CONSTANT_ANGLE

>Reconstruction Diameter

(0018,1100)

1C

The diameter in mm of the region from which data were used in creating the reconstruction of the image. Data may exist outside this region and portions of the patient may exist outside this region. See Section C.8.15.3.6.1.

Required if Reconstruction Field of View (0018,9317) is not present.

>Reconstruction Field of View

(0018,9317)

1C

The field of view width (x-dimension) followed by height (y-dimension) as used for reconstruction in mm.

Required if Reconstruction Diameter (0018,1100) is not present.

>Reconstruction Target Center (Patient)

(0018,9318)

3

The x, y, and z coordinates (in the Patient-Based Coordinate System) of the reconstruction center target point as used for reconstruction in mm. See Section C.8.15.3.6.1.

Note

If the reconstructed image is not magnified or panned the value corresponds with the Data Collection Center (0018,9313) Attribute.

>Reconstruction Target Center Location Sequence

(0018,993E)

3

An anatomically based description of a point in the patient used as the reconstruction center target point.

Note

This represents the intended reconstruction center location. They operator may or may not select a location that exactly matches this anatomical location.

>>Include Table 10.27-1 “Reference Location Macro Attributes”

BCID 1000 “CT Transverse Plane Reference Basis” for Reference Basis Code Sequence (0018,9902)

BCID 1010 “Reference Geometry - Planes” for Reference Geometry Code Sequence (0018,9903)

>Reconstruction Pixel Spacing

(0018,9322)

1

Physical distance in the patient between the center of each reconstructed pixel, specified by a numeric pair - adjacent row spacing (delimiter) adjacent column spacing in mm. See Section 10.7.1.3 for further explanation of the value order.

>Rows

(0028,0010)

1

Number of rows in the reconstructed image.

>Columns

(0028,0011)

1

Number of columns in the reconstructed image.

>Reconstruction Angle

(0018,9319)

1

Angle (in degrees) over which the data from which the frame was reconstructed was collected.

>Image Filter

(0018,9320)

3

A label describing the filter applied to the reconstructed image after the original reconstruction has been completed.

>Image Filter Description

(0018,9941)

3

A description of the nature or effect of the Image Filter (0018,9320).

E.g., sharpening, noise removing, edge enhancing.

>Derivation Code Sequence

(0008,9215)

3

Additional processing applied to the reconstructed image after image filter (if any)

>>Include Table 8.8-1 “Code Sequence Macro Attributes”

>Slice Thickness

(0018,0050)

1

Nominal reconstructed slice thickness, in mm.

>Spacing Between Slices

(0018,0088)

1

Spacing between slices, in mm. The spacing is measured from the center-to-center of each slice.

Note

Slice overlap may be constrained implicitly by constraining the Slice Thickness (0018,0050) and Spacing Between Slices (0018,0088). However, since each constraint is considered independently, the overlap may be any value resulting from the combination of allowable values for thickness and spacing.

>Window Center

(0028,1050)

3

Preferred value for Window Center (0028,1050) in the image instances produced by this reconstruction protocol element.

>Window Width

(0028,1051)

3

Preferred value for Window Width (0028,1051) in the image instances produced by this reconstruction protocol element.

>Requested Series Description

(0018,9937)

3

Requested text to copy into the Series Description(0008,103E) of the images resulting from this reconstruction protocol element.

>Content Qualification

(0018,9004)

3

Content Qualification Indicator of instances resulting from this Reconstruction Protocol Element.

Enumerated Values:

PRODUCT

RESEARCH

SERVICE

See Section C.34.12.1.


C.34.12.1 Content Qualification

Content Qualification (0018,9004), if present, specifies the value to be copied into reconstructed instances. For details on the meaning of this Attribute in those instances, see section C.8.13.2.1.1.

This Attribute does not describe the content qualification of the protocol itself.

DICOM PS3.3 2019c - Information Object Definitions