Материал: part03

Each frame in a stack has an In-Stack Position Number (0020,9057) that is the ordinal number (starting from 1) of the frame within​ the set of frames with the same Stack ID (0020,9056), see Figure C.7.6.16-4 for an example.​

Stack ID3

Stack ID2

Stack ID1

Frame Number 1-5

In-Stack Position 1 2 3 4 5

Figure C.7.6.16-4. Example of multiple stacks​

In order to allow interoperable operations on stacks, 2 different frames with the same Stack ID (0020,9056) can only have the same​ In-Stack Position Number (0020,9057) if they have the same values for the following Attributes:​

1.​Dimension Organization UID (0020,9164) to qualify the Stack ID​

2.​Image Position (Patient) (0020,0032)​

3.​Image Orientation (Patient) (0020,0037)​

4.​Rows (0028,0010) * first value of Pixel Spacing (0028,0030) (= field of view in the row direction)​

5.​Columns (0028,0011) * second value of Pixel Spacing (0028,0030) (= field of view in the column direction)​

6.​Slice Thickness (0018,0050)​

C.7.6.16.2.2.5 Frame Label​

The Frame Label (0020,9453) Attribute can be used to label frames that need to be handled as a group in application. The Dimension​ Index Pointer (0020,9165) from the Multi-frame Dimension Module may point to this Attribute if it is the base of a dimension.​

C.7.6.16.2.2.6 Temporal Position Index and Stack ID in PET images​

For PET Dynamic images, i.e., images in which Image Type (0008,0008) Value 3 is DYNAMIC, Temporal Position Index is used to​ distinguish between the multiple acquisitions of the same anatomical area. Similarly, the frames that result from one acquisition over​ the anatomic area shall be contained in one stack. Thus, for Dynamic images, Temporal Position Index (0020,9128), Stack ID​ (0020,9056), and In-Stack Position Number (0020,9057) shall be used as three of the dimensions of the image, in that order.​

Figure C.7.6.16-4b describes the usage for a PET dynamic image.​

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Temporal Position Index 3

Temporal Position Index 2

Temporal Position Index 1

Image Position

Stack ID 1

Figure C.7.6.16-4b. PET dynamic frame organization​

C.7.6.16.2.2.7 Stack ID usage in PET static, whole body and gated images​

ForstaticandwholebodyPETimages,asingleStackID(0020,9056)isusedtogroupallofthetransverseslicesovertheentireimaged​ volume together. That is, a single Stack ID (0020,9056) is used no matter how many acquisition bed positions are involved. In-Stack​ Position Number (0020,9057) is then used as the spatial dimension index. When rectangular sagittal, coronal or oblique images are​ created from these, a single Stack ID (0020,9056) is again used.​

Similarly, in cardiac or respiratory gated images, the entire volume is again identified by a single Stack ID (0020,9056), and In-Stack​ Position Number (0020,9057) is the spatial dimension index. The time dimension is indicated by one of the timing Attributes, such as​ trigger delay time or respiratory phase.​

C.7.6.16.2.2.8 Usage of Temporal Position Index, Stack ID and In-Stack Position Number in fMRI Volumes​

For fMRI volumes the Temporal Position Index is used to distinguish between the multiple volumes acquired in time (phases of a​ volume) for the same Stack ID. Each frame in the volume has an In-Stack Position Number that is the ordinal number in space of​ each volume. See Figure C.7.6.16-4c for an example.​

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...

Enhanced MRI

Image Instance 2

3

2

1 In-Stack Position

Enhanced MRI

Image Instance 1

3

2

1 In-Stack Position

Notes:

The Temporal Position Index describes the time points (phases) of a volume.

Figure C.7.6.16-4c. Example of Functional MRI volumes​

C.7.6.16.2.3 Plane Position (Patient) Macro​

Table C.7.6.16-4 specifies the Attributes of the Plane Position (Patient) Functional Group Macro.​

Table C.7.6.16-4. Plane Position (Patient) Macro Attributes​

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Note​

In the case of CT images with an Acquisition Type (0018,9302) of​ CONSTANT_ANGLE the image plane is defined to pass through the data​ collectioncenterandbenormaltothecentralrayofthedivergingX-Raybeam.​

Required if:​

•​FrameType(0008,9007)Value1ofthisframeisORIGINALandVolumetricProperties​ (0008,9206) of this frame is other than DISTORTED, or​

•​SOPClassUIDisSegmentationStorage("1.2.840.10008.5.1.4.1.1.66.4")andFrame​ of Reference UID (0020,0052) is present, or​

•​SOP Class UID is Ophthalmic Tomography Image Storage​ ("1.2.840.10008.5.1.4.1.1.77.1.5.4") and Ophthalmic Volumetric Properties Flag​ (0022,1622) is YES, or​

•​SOP Class UID is Ophthalmic Optical Coherence Tomography B-scan Volume​ Analysis Storage ("1.2.840.10008.5.1.4.1.1.77.1.5.8").​

May be present otherwise.​

C.7.6.16.2.3.1 Position and Orientation for SAMPLED Frames​

In the case of Volumetric Properties (0008,9206) having a value of SAMPLED, Image Position (0020,0032), Image Orientation​ (0020,0037) and Slice Thickness (0018,0050) shall represent the volume from which the frame was derived based on the orientation​ of the sampling performed.​

Note​

For example in the case of MAX_IP:​

The Image Orientation shall be the direction of the ray used for projection of the center of the plane.​

The image position shall contain the x, y, and z coordinates of the intersection of the mid-plane of the sampled volume with the ray​ used to project the upper left hand corner of the frame.​

The Slice Thickness shall contain the distance that the ray used for projection of the center of the plane traveled through the volume.​

C.7.6.16.2.4 Plane Orientation (Patient) Macro​

Table C.7.6.16-5 specifies the Attributes of the Plane Orientation (Patient) Functional Group Macro.​

Table C.7.6.16-5. Plane Orientation (Patient) Macro Attributes​

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C.7.6.16.2.5.1 Use of Referenced Image Macro​

ReferencedImageSequence(0008,1140)shallbeusedtoidentifyotherdataobjectsusedtoplantheacquisitionofthisimage.Instances​ referenced for this purpose shall have the same Frame of Reference UID (0020,0052) as this image. For each Item that contains​ such a reference, the value of Purpose of Reference Code Sequence (0040,A170) shall be (121311, DCM, "Localizer"). Applications​ can use the Referenced Image Sequence (0008,1140) in combination with data in Plane Position (Patient) and Plane Orientation​ (Patient) Macros to provide projections of the position of an image with respect to the referenced image.​

The Referenced Image Sequence (0008,1140) may also be present when references to other images (or frames within other images)​ are required for other reasons, as specified by Purpose of Reference Code Sequence (0040,A170).​

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