Behavior During Magnetic Resonance Imaging (Mri) - Sophysa POLARIS SPV-140 Gebrauchsanweisung

Table of Operating Pressures for Polaris® valves with pre-attached SiphonX®
SPV-140-SX
References concerned
SPVA-140-SX
0°
SiphonX® orientation
10
1
2 40
Available pressures
3 80
(mmH O)
2
4 110
5 140
When the "Valve + SiphonX®" assembly is horizontal, SiphonX® does not add any
additional resistance to the operating pressure of the Polaris® valve, and the assembly
therefore behaves like a valve on its own (cf. Figure 5).
When the "Valve + SiphonX®" assembly is vertical, SiphonX® adds 200mmH
the operating pressure of the Polaris® valve (cf. Figure 6).
Figure 6: Flow Rate - Pressure Curves for the SPV-SX Model (SPV with a pre-attached
gravitational anti-siphon device SiphonX®) in vertical position
600
500
400
300
200
100
0
0 10 20 30
Flow Rate (ml/h)
This curve is obtained by varying the applied pressure for each pressure setting and
measuring the resulting fl ow rate.
The values are given disregarding the resistance of the catheters.
Thus the pressures given on the labels of SPV-SX model correspond to the resistance
of the "Valve + SiphonX®" assembly.
The catheters add their own resistance to the shunt.
For all intermediate inclinations between the horizontal and the vertical,
the SiphonX® adds a resistance which depends on the angle of inclination (cf. Figure 7).
Figure 7: Operating pressures for the SiphonX®, SX-200 model, depending on
its inclination, whatever the fl ow rate between 5 and 50ml/h.
Angle (°)
SPV-SX, SPVA-SX,
SPVB-SX
90° 0° 90°
210 30 230
70 270
240
280 110 310
310 150 350
340 200 400
O to
2
Position 200
Position 150
Position 110
Position 70
Position 30
40 50 60
This curve is obtained by applying the following method: the measurement
concerns the upstream pressure of a 10ml/h fl ow of water passing through the
SiphonX® and the Sophysa proximal and distal catheters and by varying the angle
from 0° (horizontal) to 90° (vertical). The same curves are obtained for fl ow rates
between 5 and 50ml/h.
The measurement is performed disregarding the resistance of the catheters.
7. Behavior during Magnetic
Resonance Imaging (MRI)
A shunt consisting of a Polaris® valve (including connectors, and possibly reservoirs
and SiphonX® gravitational anti-siphon device) and its catheters, is considered
as "MR Safe" in accordance with the defi nition in the standard, ASTM F-2503-05.
A patient fi tted with a Polaris® valve can undergo an MRI examination,
even immediately after the device has been implanted.
The results of in vitro tests have demonstrated that the Polaris® valve does not
present any danger in the following examination conditions:
- MRI with a static magnetic fi eld limited to 3-Tesla
- whole body averaged SAR (Specifi c Absorption Rate) limited to 2.8 W/kg for
15 minutes exposure at 3- Tesla.
The tests conducted in accordance with the standard, ASTM F 2182-02a, showed that
the rise in temperature caused by exposure to 3-Tesla MRI was negligible and had
no physiological consequences for the patient.
Tests conducted in accordance with standards, ASTM F 2213-06 and ASTM F 2052-06,
showed that the torque and displacement force induced by a magnetic fi eld of 3 Tesla
or less did not present any risks for the patient.
N :
OTE
T
HE PATIENT MUST BE INFORMED THAT HE
,
WHICH IS COMPLETELY INOFFENSIVE DURING AN
Tests have demonstrated that the performance (operating pressures calibration),
magnetic properties and functionality (valve can still be adjusted and self-locking
mechanism of the rotor remains functional) of the Polaris® valve are not aff ected
by even repeated exposure to MRI examinations MRI from 1.5 Tesla to 3 Tesla
(30,000 Gauss).
The Polaris® valve mechanism is designed to prevent accidental changes in operating
pressure in the standard conditions for MRI examination at 3 Tesla or less, as long as
there is no rotational movement on the valve during MRI exposure.
W :
ARNING
E -
VEN THOUGH THE SELF LOCKING SYSTEM OF THE VALVE WAS DESIGNED TO BE INSENSITIVE TO
,
MAGNETIC FIELDS IT IS RECOMMENDED THAT THE PRESSURE SETTING OF THE VALVE IS CHECKED BEFORE
MRI .
AND AFTER THE EXAMINATION
P :
RECAUTIONS
D MRI ,
URING EXAMINATIONS MAKE SURE THE PATIENT REMAINS IMMOBILE IN THE IMMEDIATE
.
PROXIMITY TO THE TUNNEL AND INSIDE IT
I
F THERE IS A ROTATIONAL MOVEMENT ON THE VALVE SIMULTANEOUS WITH EXPOSURE TO A POWERFUL
( : 3-T MRI)
MAGNETIC FIELD FOR EXAMPLE ESLA
.
BEING ACCIDENTALLY CHANGED
C P ®
HOOSE A OLARIS VALVE IMPLANTATION SITE AWAY FROM AREAS OF SIGNIFICANT CLINICAL
, ,
INTEREST SUCH AS A TUMOR THAT MAY REQUIRE REPEATED FUTURE
- P ®
THE MICRO MAGNETS IN OLARIS VALVE ARE A POTENTIAL SOURCE OF ARTIFACTS ON
T
HE SIZE OF THESE ARTIFACTS COULD BE VERY LARGE IN SIZE IN RELATION TO THE SIZE AND SHAPE
.
OF THE VALVE
9
/
SHE IS LIKELY TO FEEL SLIGHT DISCOMFORT
MRI .
EXAMINATION
THERE IS A POSSIBLE RISK OF THE PRESSURE SETTING
MRI . I
EXAMINATIONS NDEED
MRI
IMAGES
,
.