A.14 X-Ray Angiographic Image Information Object Definition

A.14.1 XA Image IOD Description

This Section defines the Information Object for single plane X-Ray Angiographic Imaging that includes those data elements and information objects necessary for the interchange of digital X-Ray Angiographic data. This includes images of the heart and all blood vessels.

The XA IOD share a significant amount of common information with the XRF IOD. The differences between the two IODs are that the XRF Image IOD includes a tomography module; and the two IODs utilize different methods to specify positioner angles. The XRF Image IOD contains a single column angulation Data Element that uses an equipment based coordinate system, while XA Image IOD c-arm positioner angles are specified in a patient based coordinate system. RF applications that support a patient-based coordinate system with cranial/caudal, LAO/RAO angles may utilize the XA IOD.

The XA IOD is also applicable to clinical areas other than angiography (e.g. Interventional Procedures, Myelography, Biopsy/Localization, and Neurology).

Note: 1. For the purpose of X-Ray Angiography (XA), this IOD can be used to encode a single frame image, or a Cine Run encoded in a single multi-frame image.

2. A typical study might include all the images generated between the time a patient gets on and gets off the procedure table. As several separable diagnostic or therapeutic processes may occur during a single study (e.g., pre-intervention CA, left ventriculography, and post-intervention CA), a series may be defined as comprising a set of images (single or Multi-Frame) associated with one such process within a study.

3. This IOD can be used to encode a single plane acquisition, or one plane of a biplane acquisition.

A.14.2 XA Image IOD Entity-Relationship Model

The E-R Model in Section A.1.2 depicts those components of the DICOM Application Information Model that directly reference the X-Ray Angiographic Image IOD, with exception of the Frame of Reference and Modality LUT entities, which are not used. Additionally, "Image" in Figure A.1-1 may represent a Single Frame or a Multi-Frame image. A frame denotes a two-dimensional organization of pixels recorded as a single exposure.

A.14.3 XA Image IOD Module Table

Table A.14-1X-RAY ANGIOGRAPHIC IMAGE IOD MODULES

IE Module Reference Usage
Patient Patient C.7.1.1 M
Clinical Trial Subject C.7.1.3 U
Study General Study C.7.2.1 M
Patient Study C.7.2.2 U
Clinical Trial Study C.7.2.3 U
Series General Series C.7.3.1 M
Clinical Trial Series C.7.3.2 U
Frame of Reference Synchronization C.7.4.2 U
Equipment General Equipment C.7.5.1 M
Image General Image C.7.6.1 M
Image Pixel C.7.6.3 M
Contrast/Bolus C.7.6.4 C - Required if contrast media was used in this Image
Cine C.7.6.5 C - Required if pixel data is Multi-Frame Cine data
Multi-Frame C.7.6.6 C - Required if pixel data is Multi-Frame Cine data
Frame Pointers C.7.6.9 U
Mask C.7.6.10 C - Required if the Image may be subtracted
Display Shutter C.7.6.11 U
Device C.7.6.12 U
Intervention C.7.6.13 U
Specimen C.7.6.22 U
X-Ray Image C.8.7.1 M
X-Ray Acquisition C.8.7.2 M
X-Ray Collimator C.8.7.3 U
X-Ray Table C.8.7.4 C - Required if Image is created with table motion, may be present otherwise
XA Positioner C.8.7.5 M
DX Detector C.8.11.4 U
Overlay Plane C.9.2 U
Multi-Frame Overlay C.9.3 C - Required if Overlay data contains multiple frames.
Modality LUT C.11.1 C - Required if Pixel Intensity Relationship (0028,1040) is LOG U - Optional if Pixel Intensity Relationship (0028,1040) is DISP
VOI LUT C.11.2 U
SOP Common C.12.1 M
Frame Extraction C.12.3 C - Required if the SOP Instance was created in response to a Frame-Level retrieve request

Note: The Curve Module was previously included in the Image IE for this IOD but has been retired. See PS 3.3 2004.