GE LOGIQ S8, Руководство по обслуживанию

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GE H
EALTHCARE
D
IRECTION
5394227, 12 LOGIQ S8/LOGIQ E8 S
ERVICE
M
ANUAL
Section 6-3 - Volume Navigation Calibration Procedure 6 - 11
6-3-4 Setup
Connect a service key to the system. Set the system up for V Nav by connecting the transmitter and
sensors. Attach the sensor/biopsy bracket to the probe, making sure to use the correct bracket for the
probe. Connect sensors 1 and 2, assuring that their positions are not swapped. Put the phantom
(optional) in a location where it does not rock or otherwise move while it is being scanned. Make sure
to avoid areas with metal. Adjust the transmitter so that the bottom of the transmitter is at about the same
level as the top of the phantom (optional). The top, center of the phantom (optional) should be about 8-
16 inches (20-40 cm) from the face of the transmitter.
The calibration environment
must
be tested for electromagnetic field distortions. Calibrating in an
environment with electromagnetic field distortions will likely generate a field calibration correction less
accurate than the factory calibration.
1.) Enter V Nav by pressing the
V Nav
key.
2.) Set the
Magnetic Distortions
control (see the touch panel) to “Show All.”
- Move the windows pointer over the 2nd Environmental Quality Indicator in the upper left
corner of the screen to initiate a mouse over window.
3.) Move the transducer across the surfaces of the phantom (optional) where you will be scanning.
The absolute value of the magnetic distortion reading (“1-2 Distortion”) should be consistently less than
1 mm, especially since the transducer is held steady in one location. It is also important that the reading
is not cycling quickly between values such as continuously looping from -0.2 to 0.6. The environmental
quality for both sensor 1 and sensor 2 should be in the green range, preferably at 6 or 7 bars.
Scanning the phantom (optional), place a GPS Marker on a point of interest. Holding the probe steady,
the point should not drift or move in a large circle. Turn the transducer 90 degrees and confirm that the
GPS Marker is still tracking the point of interest.
Problem 1 – Distortion reading is too large. Attempt to adjust the environment by removing or moving
away from metal and adjusting the placement of the transmitter. If the distortion is not updating at all,
the second sensor may be bad.
Problem 2 – Distortion is cycling or GPS Marker is circling when the probe is steady. Make sure the
transmitter is close enough to the phantom (optional).
Problem 3 – The GPS Marker does not track the point of interest when the transducer is turned. Verify
that sensors 1 and 2 are not swapped.