DICOM PS3.17 2021d - Explanatory Information

TTT.2.6.4 Example (Current)
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#### TTT.2.6.4 Example

In this example, two rotational images are acquired; the first one before the intervention and the second one after the intervention. They are encoded with the Instance UIDs "C1" and "C2" respectively.

In both rotational acquisitions, the patient position with respect to the table is head-first prone, and the table is not rotated nor tilted with respect to the Isocenter. The patient coordinates and the Isocenter coordinates are then aligned on x, y and z.

The patient origin is defined by the application as a fixed point on the table.

During the first rotational acquisition, the table position with respect to the Isocenter in the lateral direction [x] is +20mm, in the vertical direction [y] is +40mm, and in the longitudinal direction [z] is +60mm.

During the second rotational acquisition, the table position with respect to the Isocenter in the lateral direction [x] is -10mm, in the vertical direction [y] is +80mm, and in the longitudinal direction [z] is +110mm.

The second acquisition is performed with a relative table movement of (-30,40,50) mm vs. the first acquisition in the patient coordinates system. Therefore, for a given 3D slice "i" of the two volumes, the Image Position (Patient) (0020,0032) of the second volume is translated of (+30,-40,-50) mm vs. the Image Position (Patient) (0020,0032) of the first volume.

The two reconstructions are performed with the same number of rows, columns and slices, and both at the same resolution of 0.2 mm/voxel. Note that if the resolution was different, the Image Position (Patient) (0020,0032) of the second volume would be additionally translated by the shift of the TLHC pixels relative to the center of the volume, because both volumes are centered at the Isocenter.

The reconstructions are encoded in two X-Ray 3D Angiographic instances of Instance UIDs "Z1" and "Z2" respectively.

Figure TTT.2.6-3. Attributes of the pre-intervention 3D reconstruction

Figure TTT.2.6-4. Attributes of the post-intervention 3D reconstruction

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DICOM PS3.17 2021d - Explanatory Information