brain to the peritoneal cavity. Each kit
contains either a NOVUS or NOVUS
Mini Valve, a Pudenz Ventricular
Catheter and an integral, open-ended
kink resistant catheter attached to the
outlet of the valve.
The kits are available in low, medium
and high pressure ranges. All valves
and catheters contain barium sulfate for
x-ray detectability. No metal parts are
used anywhere in the system, to
eliminate any possibility of interference
with CT scanning or MR imaging.
NOVUS Models
The NOVUS Models have a contoured
base which facilitates choice of
placement remote from the burr hole. A
silicone elastomer T- valve within the
assembly is designed to provide shunt
pressure control and to help prevent
backward flow of CSF into the
ventricles of the brain.
Three valve closing pressure ranges are
available to provide the surgeon with a
choice in meeting individual patient
needs. Each valve is individually tested
at the time of manufacture for
conformance with labeled closing
pressure performance characteristics.
The closing pressure ranges are
identified by a tantalum-impregnated
silicone elastomer dot code on the
valve dome.
Valve performance characteristics are
reported in accordance with a shunt
valve test method contained in the
American Society for Testing and
Materials F647-86, "Standard Practice
for Evaluating and Specifying
Implantable Shunt Assemblies for
Neurosurgical Application" and by valve
closing pressure for the convenience of
performance verification prior to
implantation by the surgeon. For a
description of the preimplant check for
valve patency and valve performance,
please refer to Instructions for Use. Due
to characteristics of silicone materials,
some variation in pressure
performance may occur.
In order to allow the valve assembly to
control shunt pressure, Integra
NeuroSciences recommends the use of
a low-pressure distal catheter (closing
pressure 54mm H
O or less) such as
2
the Integra NeuroSciences Peritoneal
Reflux Control Catheter (Catalog No.
NL850-1375) or Peritoneal Open-Ended
Ventricular Catheter Guide
Catheter (Catalog No. NL850-1376).
See Instructions for Use.
The valve flushing chamber may be
penetrated by a 25-gauge or smaller
needle. Such penetration permits
removal of CSF samples, as well as the
injection of fluid materials in either the
proximal or distal direction. The
flushing chamber is marked with an
arrow to indicate the CSF flow
direction, which facilitates proper valve
placement.
Physiological Flow Device
All models possess a Physiological
Flow Device which also serves as distal
occluder. This device is designed to
help prevent the excessive drainage of
cerebrospinal fluid which would
otherwise be caused by the siphoning
effect created by the elevation of the
ventricular catheter with respect to the
distal catheter (i.e. when the patient
sits, stands or is held erect). This
siphoning effect is minimized by the
physiological flow device, which closes
under normal physiological negative
pressure, yet will reopen to allow the
flow of CSF to resume before
intraventricular pressure becomes
excessive. The Physiological Flow
Device is designed to restrict flow when
the shunt system is under substantial
negative hydrostatic pressure. It is not
designed to compensate for lowered
intracranial pressure brought on by
other than large negative hydrostatic
pressure changes.
Indications
The NOVUS and NOVUS Mini
Valves utilized in the treatment of
hydrocephalic patients are components
in systems designed to shunt
cerebrospinal fluid from the lateral
ventricles of the brain into either the
right atrium of the heart or the
peritoneum.
The NOVUS Mini valve can be used in
(but is not restricted to) situations
2
where skin erosion may be a problem,
as with older patients.
Valves with a Physiological Flow Device
are intended to reduce the hazard of
negative intraventricular pressure (with
respect to atmospheric pressure) when
the patient is sitting, standing or
semirecumbent.
Contraindications
Ventriculoatrial or ventriculoperitoneal
shunting systems should not be used in
the presence of known or suspected
infections along the course of the shunt
(meningitis, ventriculitis, skin
infections, bacteremia, septicemia, or
peritonitis). It is advisable to avoid
shunting procedures if infection is
present anywhere in the body.
The ventriculoatrial method of shunting
is contraindicated for patients with
congenital heart disease or other
anomalies of the cardiopulmonary
system.
Instructions for Use
Valve Patency and Closing Test
Note: There is no basic, concise test
which can be performed under
operating room conditions to measure
specific valve pressure. The following
test is provided only to confirm patency
prior to implantation.
1.Connect a length of sterile tubing
(approximately 25cm) to the proximal
connector. No tubing should be
connected to the outlet tube.
2. Orient the valve horizontally on the
test table.
3. Using a syringe, gently fill the tube.
Use sterile deaerated water to help
eliminate air bubbles in tubing and
valve.
4. After flow through tubing and valve
has been established, examine tubing
and valve to insure bubbles have been
eliminated. Do not flush the valve
with a syringe. The amount of
pressure created by syringe flushing
will temporarily deform the silicone
elastomer valve, which may cause
abnormally low pressure test results.
5. Elevate the tubing vertically above
the valve. A noticeable slowing of flow