GE Healthcare eXplore Locus SP, Руководство по обслуживанию

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h. Make a note of this value in the Worksheet. This is the ideal Centre of Rotation at the
Central Slice.
36. Click the Advanced button in the Reconstruction Utility window, and choose the
Reconstruction tab.
37. De-select the Short Scan field and click OK .
38. Click the Recon button in the Reconstruction Utility window.
39. Name the file 1x1_wire_cs_360 (or 2x2_wire_cs_360 or 4x4_wire_cs_360 depending on
which verification scans are being performed)
40. Confirm the wires are still round in MicroView . The wires should appear even rounder. Exit
MicroView .
Note: If the wires appear hollow (like a ring) in the 360 degree reconstruction, then the Centre of
Rotation needs to be adjusted as described above. Also, verify that the HU calibration values
are set to -1.
This process has determined the ideal Centre of Rotation of the wire phantom at the Central Slice.
The following steps check the Centre of Rotation of the image at either end of the wire phantom.
VERIFY CENTRE OF ROTATION AT EACH END (FOR 1X1 MODE ONLY ):
1. Change the Z-Origin field on the Reconstruction Utility window to 200 . This represents one
end of the wire phantom.
2. Click the Advanced button, then choose the Reconstruction tab.
3. Re-select Short Scan, then click OK .
4. Click the Recon button. Name the file 1x1wire_-end_ss
5. View the image in MicroView . The wires should appear as round as possible.
If the wires are not round, the Centre of Rotation needs to be adjusted as described above.
6. Upon completion, make note of the difference between this Centre of Rotation and the ideal
Centre of Rotation at the Central Slice, in the Worksheet.
Note: The value of the Centre of Rotation at either end of the wire phantom may only differ from the
ideal Centre of Rotation at the Central Slice by 1.5 pixels. The Short Scan option in
Reconstruction Utility must be used for this test to be valid.
7. Change the centre of rotation back to the ideal found at the Central Slice and repeat the
reconstruction with all 360 views (de-select the Short Scan field). Name the file
1x1wire_-
end_360 . Verify that the wires appear round.
8. Move to the other end of the wire phantom by changing the Z-Origin to 2600 . Re-select the
Short Scan field. Name the file 1end_ss