Hologic DISCOVERY A, Техническое руководство

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Discovery QDR Series Technical Manual
3-65
Each service engineer has been provided with an 11-step aluminum phantom (Step Wedge
Penetrometer, P/N 099-0716) for checking image contrast and a line-pair phantom (X-ray
Test Pattern, P/N 099-0715) for verifying scan resolution.
Checking the quality of the IVA scans requires three scans:
• single-energy AP
• single-energy lateral
• dual-energy AP
To perform an IVA scan QC, do the following:
1. Press the
Center Table
button to center the table.
2. Press the
Laser
button to turn the laser ON. If the laser goes off during the align-
ment process just press the
Laser
button again to turn the laser ON.
3. Place the x-ray Step Wedge Phantom (P/N 099-0716) on the table approximately
an inch to the right of the crosshair. Center the laser line approximately through
the center of the Step Wedge.
4. The Step Wedge Phantom should be placed with its thickest end to the left (foot
end) and its thinnest end on the right with its edges parallel to the table.
5. Skip steps 6 through 8 for Models Ci and Wi.
6. The X-ray Test Pattern Phantom (P/N 099-0715) should be aligned approxi-
mately an inch to the right of the Step Wedge Phantom.
7. The x-ray test pattern should be placed on the table with the lines the Test Pattern
Phantom perpendicular to the motion of the C-arm during scanning. The laser
line should pass through the center of the x-ray Test Pattern Phantom. The 1.8
and 0.6 test patterns should be farthest from the Step Wedge Phantom. The 0.6
test pattern should be nearest to the front of the table.
8. Depress the
Laser
button on the C-Arm to turn OFF the laser.
9. Click the
Perform Exam
button at the Discovery Main Screen.
10. Select the
IVA Test
as the patient. If this name is not present, then click the
New
patient
button. Enter
IVA Test
as the new patient last name. Leave the first
name and initials blank and then click the
OK
button.
11. Click the name
IVA Test
from the patient names. Click the
OK
button.
12. In
Patient Confirmation
Screen, click the
OK
button.
13. At the
Select Scan Type
screen, select
IVA Imaging
.
14. Uncheck the
Use default scan mode
check box and then click the
Next>>
but-
ton.
15. Select
SE AP Image
then click the
Next>>
button.
16. Select
None
then click the
Next>>
button.
17. From the
Scan Parameters
screen set the scan length to 10.0 inches.