Galil Visual-ICE MRI, Руководство пользователя

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5-6 User Manual
NOTE: Throughout the procedure, monitor the amount of gas time remaining in the cylinders
using the Gas Indicator on the
Navigation Tool Bar
(Screen 5-3). If it is necessary to change the
gas cylinders during a procedure, follow the instructions provided in Section 5.4.
Screen 5-3. Gas Time Remaining
5. Press the Freeze button on selected channels containing needles to begin the initial freeze phase
of the procedure.
To adjust the freeze intensity, press the
Freeze Intensity button and select the desired intensity
from the drop-down menu. The Freeze phase will continue at the selected freeze level until this
operation is changed or stopped.
CAUTION. Continuously monitor iceball formation using image guidance to ensure adequate
tissue coverage and to avoid damage to adjacent structures.
OPTIONAL:
To initiate a freeze phase on all needles simultaneously, press the Freeze button
on the channel labeled ALL. Pressing any function button on the channel labeled ALL displays a
messageaskingyoutoconfirmsimultaneousoperationofallneedles.
NOTE: Selecting ALL will initiate a Freeze phase at the intensity selected for each channel.
To conduct freezing in all active channels at the same intensity, select the intensity in the ALL
channel before pressing the Freeze button.
6. Watch the timer to monitor the freeze phase elapsed time (reference Section 3.3.5 for instructions
on enlarging the timer display). When the desired freeze duration has elapsed, press the Stop
button to enter an idle phase.
CAUTION.
At the end of the freeze phase, the gas in the Junction Box Harnesses is vented
through the Console. The venting sound might be startling to people in the vicinity. The duration
of venting depends on the combined length of the two Junction Box Harnesses. A typical venting
duration after freezing is about 10 seconds.
7. To actively thaw the iceball, press the Thaw button on the channels containing needles to start
the thaw phase.
CAUTION.
Scanning with a high SAR sequence while thawing could result in thermal injury due
to needle heating.
OPTIONAL:
To initiate a thaw phase on all needles simultaneously, press the Thaw button on
the channel labeled ALL . Pressing any function button on the channel labeled ALL displays a
messageaskingyoutoconfirmsimultaneousoperationofallneedles
.
8. Watch the timer to monitor the thaw phase elapsed time (reference Section 6.2.3 for instructions
on performing a timed thaw phase). When the desired thaw duration has elapsed, press the Stop
button to enter an idle phase.
CAUTION. At the end of the thaw phase, the gas in the Junction Box Harnesses is vented
through the Console. The venting sound might be startling to people in the vicinity. A typical
duration for helium gas venting after thawing is about 3 seconds.
9. Repeat Steps 4 through 8 until the desired number of freeze-thaw cycles has been completed.
CAUTION. Ensure adequate thawing before attempting to remove needles from the patient.
Discontinue all needle operation prior to needle removal to minimize risk of tissue injury.