Confi Gurations Of The Polaris® Adjustable Pressure Valve; Measurement Unit And Calibration Of Operating Pressures - Sophysa POLARIS SPV-140 Gebrauchsanweisung

There are two lateral lugs [1] to enable it to be positioned correctly.
The insertion of the Magnet into the Locator makes it possible:
- to unlock the valve
- to adjust the operating pressure by turning the Magnet.
Clockwise rotation increases the operating pressure of the valve, while counter-
clockwise rotation reduces it.
A green marker [2] pointing to the pressure values in the Locator reading area
and the "clicks" produced when the Magnet rotates make it possible to determine
the successive operating pressures set by the Magnet.
Removing the Magnet activates the automatic re-locking of the valve rotor due to
the mutual attraction of the two mobile micro-magnets.
P :
RECAUTIONS
D
O NOT STORE OR HANDLE THE MAGNET NEAR ANY DEVICE LIKELY TO BE AFFECTED BY A POWERFUL
.
MAGNETIC FIELD
D
O NOT PLACE THE MAGNET CLOSE TO A POWERFUL MAGNETIC FIELD
,
A DANGEROUS PROJECTILE OR ITS PERFORMANCE COULD BE ADVERSELY AFFECTED
H
ANDLE THE MAGNET WITH CARE NEAR METALLIC OBJECTS
BE A VERY FORCEFUL ATTRACTION BETWEEN THEM
5. Confi gurations of the Polaris®
Adjustable Pressure Valve
The Polaris® adjustable pressure valve is available in 4 diff erent pressure ranges,
each of which off ers 5 pressures (cf. §3 - Table of Operating Pressures).
The Polaris® valves in the "standard" pressure ranges (30-200mmH
in 3 models:
- without a reservoir (SPV)
- with an integrated reservoir of the antechamber type (SPVA)
- with an integrated reservoir of the burr hole type (SPVB).
These 3 models are available as the valve alone or as a complete kit (Figures 1 & 2).
The Polaris® valves in the " special " pressure ranges (10-140, 50-300,
and 80-400mmH O) are available in 2 models:
2
- without a reservoir (SPV-140, SPV-300 and SPV-400)
- with an integrated reservoir of the antechamber type (SPVA-140, SPVA-300
and SPVA-400)
These "special pressure" valves are not available as complete kits; only the valve is
available.
The standard pressure Polaris® valves (SPV, SPVA and SPVB), as well as the special
low pressure valves (SPV-140 and SPVA-140), are also available with a SiphonX®
"gravitational" anti-siphon device, pre-connected downstream of the valve.
SiphonX® thus makes it possible to add additional resistance to the operating
pressure of the Polaris® valve. This resistance depends on the position of the patient
(cf. §6 - Table of Operating Pressures for Polaris® valves with pre-attached SiphonX®).
The 5 corresponding models (SPV-SX, SPVA-SX, SPVB-SX, SPV-140-SX and SPVA-140-SX)
are only available as the valve alone form (with pre-attached anti-siphon device) and
are not available as complete kits.
Sophysa off ers a complete range of ventricular and distal radio-opaque catheters
which allow the CSF to fl ow to the valve and from the valve to the peritoneum or right
atrium respectively, depending upon the type of shunt chosen by the neurosurgeon.
A complete Polaris® shunt system must consist of a ventricular catheter, a Polaris®
valve and a distal catheter (atrial or peritoneal).
Patient Identifi cation Card
Each Polaris® valve is packaged with a Patient Identifi cation Card (PIC) and
traceability labels.
( . .: MRI). I
E G T COULD BECOME
.
( . . ). T
E G HOSPITAL FURNITURE HERE COULD
.
O) are available
2
The surgeon is responsible for fi lling in this Patient Identifi cation Card and giving it
back to the patient.
6. Measurement Unit and
Calibration of Operating Pressures
The pressures mentioned are in mmH
1 mmH O corresponds to 9.807 Pa or 0.074 mmHg.
2
The valves are calibrated on the basis of a fl ow rate of 10ml/h.
Each valve is tested individually: the measurement concerns the upstream pressure
of a 10ml/h fl ow of water passing through the valve and the Sophysa proximal and
distal catheters.
The calibration is performed disregarding the resistance of the catheters.
Thus the pressures given on the valve labels correspond to the resistance of the valve
alone.
The catheters add their own resistance to the shunt.
The reservoirs are not considered to have any particular resistance.
The calibration of SPV valves is performed with a tolerance of -10/+15mmH
on the measured pressures.
Figure 5: Flow Rate - Pressure Curves for the SPV Model
350
300
250
200
150
100
50
0
0 10 20
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.
Table of mean values at 10ml/h for each position setting of the Polaris® valve,
and corresponding values at 20ml/h:
SPV Polaris ® valve
position setting
Position 1
Position 2
Position 3
Position 4
Position 5
The eff ects on the device operating pressure of changes in the position of the patient
and of sub-cutaneous pressure are negligible.
Case of a valve preconnected to a SiphonX® gravitational anti-siphon device
In this case, the position of the patient has a direct infl uence on the system operating
pressure (cf. Table hereafter):
8
O.
2
30 40 50 60
Flow Rate (ml/h)
at 10ml/h
at 20ml/h
(mmH O)
(mmH
2
30
70
110
150
200
O
2
Position 200
Position 150
Position 110
Position 70
Position 30
O)
2
35
75
115
160
225