C.18.6 Spatial Coordinates Macro

Table C.18.6-1 specifies the Attributes that convey Spatial Coordinates in an SCOORD Content Item. An SCOORD Content Item shall always be the Source Content Item of one or more SELECTED FROM Relationships with IMAGE Target Content Items. Each IMAGE Target Content Item shall contain a reference to one single frame or multi-frame Image.

Note: The same set of spatial coordinates may be selected from more than one single-frame image, or more than one frame of a multi-frame image when the purpose of reference is applicable to multiple images. For example, the spatial coordinates may specify the outline of a sampling region at the same spatial location on multiple images acquired over time.

Table C.18.6-1

SPATIAL COORDINATES MACRO ATTRIBUTES

Attribute Name Tag Type Attribute Description
Graphic Data (0070,0022) 1 An ordered set of (column,row) pairs that denote positions in an image specified with sub-pixel resolution such that the origin at the TLHC of the TLHC pixel is 0.0\0.0, the BRHC of the TLHC pixel is 1.0\1.0, and the BRHC of the BRHC pixel is Columns\Rows. The values must be within the range 0\0 to Columns\Rows. The values Columns (0028,0011) and Rows (0028,0010) are those contained in the referenced image. See C.18.6.1.1 for further explanation.
Graphic Type (0070,0023) 1 See C.18.6.1.2 for Enumerated Values.
Fiducial UID (0070,031A) 3 The globally unique identifier for this fiducial item. Note: The fiducial UID can be used to associate this set of graphics with other Content Items.

C.18.6.1 Spatial Coordinates Macro Attribute Descriptions

C.18.6.1.1 Graphic Data

Graphic Data may be used to associate an anatomic or spatial Concept with a defined subset of one or more images. Graphic Data may be explicitly defined as a single point (i.e. to denote the epicenter of an anatomic site or lesion) or more than one point (i.e. representing a set of points or an open or closed polygon).

Note: Spatial coordinates may be used to associate observational data with a set of Image features. Spatial coordinates also may be used to convey coordinates that are input data for a measurement.

C.18.6.1.2 Graphic Type

When annotation applies to an image, this attribute defines the type of geometry of the annotated region of interest. The following Enumerated Values are specified for image spatial coordinate geometries:

POINT = a single pixel denoted by a single (column,row) pair

MULTIPOINT = multiple pixels each denoted by an (column,row) pair

POLYLINE = a series of connected line segments with ordered vertices denoted by (column,row) pairs; if the first and last vertices are the same it is a closed polygon

CIRCLE = a circle defined by two (column,row) pairs. The first point is the central pixel. The second point is a pixel on the perimeter of the circle.

ELLIPSE = an ellipse defined by four pixel (column,row) pairs, the first two points specifying the endpoints of the major axis and the second two points specifying the endpoints of the minor axis of an ellipse