DICOM PS3.17 2021e - Explanatory Information

AAAA.5 Two XA Devices For Acquisition and Reconstruction

This example is intended to illustrate the encoding mechanisms of the DICOM XA Protocol Storage IODs, not to suggest particular values for clinical use. Further, this example does not contain the many detailed Attributes one would expect from a fully executable defined protocol generated by an XA device, but it demonstrates the usage of some common Attributes.

This section includes an example of two Defined Procedure Protocols, one in the acquisition device, the other in the 3D reconstruction device. This example illustrates the workflow where the user selects one acquisition protocol on the acquisition device, acquires one rotational image, this image is sent to the 3D reconstruction device, and the 3D reconstruction is performed based on the protocol references of the image header.

AAAA.5.1 Acquisition and Storage Protocol

Table AAAA.5-1 contains some attributes of the Defined Procedure Protocol in the acquisition device, showing its SOP Instance UID which will be referenced further on the images and on the protocol in the 3D Reconstruction workstation. This table includes the acquisition and storage protocol elements.

Table AAAA.5-1. Acquisition and Storage Protocol

Attribute

Tag

Value

SOP Class UID

(0008,0016)

1.2.840.10008.5.1.4.1.1.200.7

(XA Defined Procedure Protocol Storage)

SOP Instance UID

(0008,0018)

UID_01

Acquisition Protocol Element Specification Sequence

(0018,991F)

>Protocol Element Number

(0018,9921)

3

>Parameters Specification Sequence

(0018,9913)

>>See Table AAAA.5-1a “Third Acquisition Protocol Element Specification - ROTATIONAL SUB ACQ”

Storage Protocol Element Specification Sequence

(0018,9935)

>Protocol Element Number

(0018,9921)

1

>Parameters Specification Sequence

(0018,9913)

>>See Table AAAA.5-1b “First Storage Protocol Element Specification - SEND TO 3D WS”


Table AAAA.5-1a and Table AAAA.5-1b reflect the semantic contents of constraint sequences but not the actual structure of the IOD. The rows in italics clarify the context of the constrained Attributes that follow by indicating which sequence in the performed module contains the constrained Attribute (as specified in the Selector Sequence Pointer).

In this example, the acquisition device includes the acquisition protocol element for the rotational acquisition, as well as one storage protocol element to send to the 3D Workstation all the images acquired with the rotational Acquisition Element #3. This is indicated in the attribute Source Acquisition Protocol Element Number (0018,9938) of the Storage Protocol Element.

Table AAAA.5-1a. Third Acquisition Protocol Element Specification - ROTATIONAL SUB ACQ

Attribute

Selector Attribute (0072,0026)

Selector Value Number (0072,0028)

Selector Sequence Pointer (0072,0052)

Selector Sequence Pointer Items (0074,1057)

Constraint Type

Constraint Value

Acquisition Protocol Element Sequence (0018,9920)

Protocol Element Number

(0018,9921)

1

(0018,9920)

1

EQUAL

3

Protocol Element Name

(0018,9922)

1

(0018,9920)

1

EQUAL

"ROTATIONAL SUB ACQ"

Acquisition Mode

(0018,11B0)

1

(0018,9920)

1

EQUAL

"Rotational"


Table AAAA.5-1b. First Storage Protocol Element Specification - SEND TO 3D WS

Attribute

Selector Attribute (0072,0026)

Selector Value Number (0072,0028)

Selector Sequence Pointer (0072,0052)

Selector Sequence Pointer Items (0074,1057)

Constraint Type

Constraint Value

Storage Protocol Element Sequence (0018,9936)

Protocol Element Number

(0018,9921)

1

(0018,9936)

1

EQUAL

1

Protocol Element Name

(0018,9922)

1

(0018,9936)

1

EQUAL

"SEND TO 3D WS"

Protocol Element Purpose

(0018,9924)

1

(0018,9936)

1

EQUAL

"For 3D Reconstruction"

Source Acquisition Protocol Element Number

(0018,9938)

1

(0018,9936)

1

EQUAL

3

>Output Information Sequence (0040,4033)

>>DICOM Retrieval Sequence (0040,4071)

Destination AE

(2100,0140)

1

(0018,9936) \

(0040,4033) \ (0040,4071)

1\1\1

EQUAL

"AET_3D_WS"


DICOM PS3.17 2021e - Explanatory Information