GE Healthcare eXplore Locus SP, Service Manual

Page: 168 / 266

GE H
EALTHCARE
D
IRECTION
5158821-100, R
EVISION
3
E
X
PLORE
L
OCUS
SP S
ERVICE
G
UIDE
Page 168
24. Move the mouse to the right
line (side) and press 2 at the
Full Width Half Maximum
value point to draw a line from
one side to the other.
25. Make note of the line length
in pixels, in the Worksheet.
26. In eXplore Scan Manager ,
navigate to the 1x1wire scan.
Note the resolution value
displayed on the right-hand
side of the window, in the
Worksheet.
27. Divide .025mm (which is the
size of the wire in the wire
phantom) by the resolution
value and then add 2 to the
result. This value is the target
value, in pixels, of the wire
scan. Record in Worksheet.
Example:
.025 ÷ .007634 = 3.274 (target value)
3.274 + 2 = 5.274 (maximum value)
28. Verify that the line length calculated in step 25 is less than the maximum value calculated in
step 27. If not, calibration will need to be restarted.
29. Repeat steps 15 to 28 for the remaining 3 wires.
30. Exit the plot, then exit MicroView .
Upon completion:
In the Reconstruction Utility , press the Advanced button. Go to the Recon tab. Re-enter the noted
air, water and bone HU calibration values into each field for all three scans (1x1, 2x2 and 4x4)
Inform the customer that they may need to re-calibrate their HU values.