Magnetic Resonance Imaging (Mri) - Medtronic SYNCHROMED EL serie Gebrauchsanweisung

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Magnetic Resonance Imaging (MRI)

Magnetic Resonance Imaging (MRI) will temporarily stop the rotor of the pump
motor due to the magnetic field of the MRI scanner and suspend drug infusion
for the duration of MRI exposure. The pump should resume normal operation
upon termination of MRI exposure. Prior to MRI, the physician should determine
if the patient can safely be deprived of drug delivery. If the patient cannot be
safely deprived of drug delivery, alternative delivery methods for the drug can be
utilized during the time required for the MRI scan. If there is concern that
depriving the patient of drug delivery may be unsafe for the patient during the
MRI procedure, medical supervision should be provided while the MRI is
conducted. Prior to scheduling an MRI scan and upon completion of the MRI
scan, or shortly thereafter, the pump status should be confirmed using the
SynchroMed programmer. In the unlikely event that any change to the pump
status has occurred, a "pump memory error" message will be displayed and the
pump will sound a Pump Memory Error Alarm (double tone). The pump should
then be reprogrammed and your Medtronic representative notified.
Testing on the SynchroMed EL pump has established the following with regard
to other MR safety issues:
Tissue Heating Adjacent to Implant During MRI Scans
Specific Absorption Rate (SAR): Presence of the pump can potentially cause a two-
fold increase of the local temperature rise in tissues near the pump. During a
20-minute pulse sequence in a 1.5 T (Tesla) GE Signa Scanner with a whole-
body average SAR of 1 W/kg, a temperature rise of 1 degree Celsius in a static
phantom was observed near the pump implanted in the "abdomen" of the
phantom. The temperature rise in a static phantom represents a worst case for
physiological temperature rise and the 20 minute scan time is representative of
a typical imaging session. Implanting the pump more lateral to the midline of
the abdomen may result in higher temperature rises in tissues near the pump.
In the unlikely event that the patient experiences uncomfortable warmth near
the pump, the MRI scan should be stopped and the scan parameters adjusted to
reduce the SAR to comfortable levels.
Peripheral Nerve Stimulation During MRI Scans
Time-Varying Gradient Magnetic Fields: Presence of the pump may potentially
cause a two-fold increase of the induced electric field in tissues near the pump.
With the pump implanted in the abdomen, using pulse sequences that have
dB/dt up to 20 T/s, the measured induced electric field near the pump is below
the threshold necessary to cause stimulation.
In the unlikely event that the patient reports stimulation during the scan, the
proper procedure is the same as for patients without implants—stop the MRI
scan and adjust the scan parameters to reduce the potential for nerve
stimulation.
Medtronic - Kerkrade / PARTNUMBER :
Precautions
198076-036 SHEETNR. :
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