Indications; Contra-Indications; Description And Operating Principle Of Polaris® Valves - Sophysa POLARIS SPV-140 Gebrauchsanweisung

W :
ARNINGS
F (USA) L
EDERAL AW RESTRICTS THIS DEVICE TO SALE BY OR ON THE ORDER OF A PHYSICIAN
R
EAD THE INSTRUCTIONS FOR USE CAREFULLY BEFORE ADJUSTING THE VALVE OPERATING PRESSURE
1.

Indications

The Polaris® adjustable pressure valve is designed for the treatment of hydrocephalus
by shunting the Cerebrospinal Fluid (CSF) to the abdominal cavity or right atrium
of the heart.
The Polaris® valve adjustment kit is designed for reading and adjusting the operating
pressure of a Polaris® valve in order to adapt to the clinical evolution of the patient.
2.

Contra-indications

The contra-indications are the following:
- established or suspected infections along the length of the shunt (meningitis,
ventriculitis, peritonitis, septicemia or bacteremia) or any infection present
in any part whatsoever of the body
- patients on anticoagulant therapy, or presenting with bleeding diathesis,
or with hemorrhagic CSF (indeed, the presence of blood in the system could
lead to an obstruction in the system)
- ventriculo-atrial shunts in patients with congenital cardiopathies or other
malformations of the cardio-pulmonary system
However, if the clinical benefi t outweighs these contra-indications, the implantation
of a shunt in such cases is performed under the responsibility of an experienced
neurosurgeon. The clinical condition of the patient must, therefore, be subject to
increased surveillance.
W :
ARNING
D
O NOT USE AN EXTERNAL SHUNTING DEVICE
THE TWO SYSTEMS COULD INTERFERE WITH EACH OTHER AND DISRUPT CONTROL OF THE DRAINAGE
3. Description and Operating principle
of Polaris® valves
Figure 3: The Polaris® adjustable pressure valve
1
2
3
4
5
6
A precision valve
The Polaris® adjustable pressure valve (Figures 1&3) is a single use implantable
device.
The Polaris® valve allows drainage of Cerebrospinal Fluid (CSF) in a given direction.
( , .)
DRAINAGE BAG ETC IN SERIES WITH A VALVE AS
7
8
9
10
11
The CSF arrives in the valve through the inlet connector [1], passes through the body
. of the valve [5] and leaves through the outlet connector [6].
.
The connectors are made of stainless steel and the body of the valve is in
polysulfone.
On either side of the inlet connector [1] are suture holes [2] which make it possible to
attach the valve to the sub-cutaneous tissues to prevent the valve from migrating.
On the upper surface of the valve an arrow [4] shows the direction of CSF fl ow through
the valve. This helps to position the valve correctly during implantation.
On the lower surface of the valve there is an individual serial number.
The valve body contains a ball-in-cone mechanism which determines the operating
pressure of the valve.
In conditions of normal use this mechanism provides an anti-refl ux function and
is not sensitive to temperature variations.
The valve body, which cannot be deformed, protects the mechanism from shocks.
It also prevents attempts at pumping or puncturing the valve and makes it insensitive
to variations in percutaneous pressure.
The Polaris® valve is a latex-free and phthalate-free product.
Adjustable pressure
The resistance of the Polaris® valve can be adjusted without re-operating, in order
to adapt it to the clinical evolution of the patient.
The principle is based on the pressure variation exerted on a ruby ball [7] by a fl at,
semi-circular spring [8] at diff erent points on its curvature.
The spring is attached to a rotor [9] which is able to rotate inside the valve body
on its ruby central axis [11].
The operating pressure of the Polaris® valve is determined by the angular position
of its rotor.
.
There are 5 pressures available. These correspond to the 5 possible positions of
the rotor.
Position No. 1 corresponds to the lowest pressure and Position No. 5 to the highest
pressure.
Titanium radio-opaque studs [10] inserted on the right-hand side of the valve body
indicate the 5 positions of the rotor/spring assembly (cf. §10 - Post-operative X-ray
examination).
The Polaris® adjustable pressure valve exists in 4 diff erent pressure ranges (cf. Table
of Operating Pressures).
To the left of the inlet connector there are radio-opaque points [3] which identify
the pressure range of the valve (Figures 3&16, and §10 - Post-operative X-ray
examination).
Table of Operating Pressures for Polaris® valves
References SPV-140
concerned SPVA-140
Identifi cation
0 point
of the range
1
2
Available
pressures
3
(mmH O)
2
4
5
6
SPV, SPV-2010
SPVA, SPVA-2010
SPVA-300
SPVB, SPVB-2010
1 point
30
10
70
40
110
80
150
110
200
140
SPV-300 SPV-400
SPVA-400
2 points 3 points
50 80
100 150
150 230
220 330
300 400