GE Healthcare eXplore Locus SP, Руководство по обслуживанию

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EALTHCARE
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IRECTION
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VERIFY STAGE TIP (SIDE-TO-SIDE MOVEMENT):
1. Move the ball toward the X-Ray Source ( 140mm right ).
2. Elevate and rotate the tool until the top bebe appears in the centre of the screen.
3. Use the mouse pointer window as a reference guide and rotate the bebe 180°.
The goal here is to have the bebe return to the same x axis after the 180° rotation.
4. Continue to reposition the bebe until it is close to returning to the same x axis.
It may be necessary to rotate the bebe less than 0.1 degree to get it in the exact centre. To
make movements that are finer than 0.1 degree access the
X-Ray and Motor Controller and
adjust the Steps to Travel field (e.g. 50) which are steps in the stepper motor. Adjust the
Direction and press the Start Motor button.
The goal here is that, at the Source end, the y values at 0 and 180 degree rotation are
within 2 pixels of each other and within 2 pixels of the Central Slice, AND the y axis at the
detector end is within 2 pixels of the Central Slice.
5. Once the bebe is properly positioned in the x direction, capture the image, correct and unwarp
it. Open the image in
MicroView and determine the y axis of the bebe using the Region Grow
tool in MicroView . This y axis must be the same as the Central Slice value (within 2 pixels)
calculated earlier. Use Worksheet to record values.
If the y axis is not the same value as the Central Slice (within 2 pixels):
6. Continue to adjust the elevation - capturing, correcting, unwarping, and viewing the images in
MicroView - until the y axis is within 2 pixels of the Central Slice value. Use the Steps to Travel
field within X-Ray and Motor Controller to make movements finer than 1mm.
Once the y axis equals the value as the Central Slice (within 2 pixels):
7. Rotate the tool 180° and capture, correct, unwarp and view the image in MicroView . The value
of this y axis must be within 2 pixels of the previous value before rotation (i.e. the value
determined in step 6). For example, if the previous y axis was 1428, this y axis may have a
value between 1426 and 1430. Also, the x value must be within 5 pixels of each other. Use
Worksheet to record values.
If not within 2 pixels, verify the Central Slice position before making any adjustments, as
follows.
Verify the Central Slice position:
- rotate the tool back 180 degrees
- move the stage 140mm toward the detector
after 180° rotation after 180° rotation