ASTM F647-22

Standard Practice for Evaluating and Specifying Implantable Shunt Assemblies for Neurosurgical Application

SIGNIFICANCE AND USE
4.1 This practice provides minimum requirements for the ensurance of safety and efficacy. It provides a common language whereby the function of these surgical implants is described.
SCOPE
1.1 This practice covers requirements for the evaluation and specification of implantable shunts as related to resistance to flow, direction of flow, materials, radiopacity, mechanical properties, finish, sterility, and labeling of shunt assemblies.  
1.2 Devices to which this practice is applicable include, but are not limited to, those that are temporarily implanted to effect external drainage; or permanently implanted to effect shunting of fluid from a cerebral ventricle, a cyst, the subarachnoid space to the peritoneal cavity, the venous circulation, or some other suitable internal delivery site, and intracranial bypass.  
1.3 Limitations—Although this practice includes a standard test method for the evaluation of pressure/flow characteristics of shunts or shunt components, it does not include specific pressure/flow requirements.  
1.4 The following components that individually or in combination comprise shunt assemblies are considered to be within the scope of this practice: catheters (such as atrial, peritoneal, ventricular), connectors, implantable accessory devices (such as antisiphon devices and reservoirs), valved catheters, and valves.
Note 1: The standards in Section 2 contain provisions that, through reference in this text, constitute provisions of this practice. At the time of publication, the editions indicated are valid. All standards are subject to revision, and parties to agreements based on this practice are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Devices or components, or both, whose structures are comparable to that outlined in these standards are acceptable.  
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 30-Sep-2022
• ICS: 11.040.40 - Implants for surgery, prosthetics and orthotics
• Technical Committee: F04 - Medical and Surgical Materials and Devices
• Drafting Committee: F04.31 - Neurosurgical Standards

Relations

• Refers: ASTM F138-19 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Dec-2019
• Refers: ASTM F67-13(2017) - Standard Specification for Unalloyed Titanium, for Surgical Implant Applications (UNS R50250, UNS R50400, UNS R50550, UNS R50700)
• Effective Date: 01-Mar-2017
• Refers: ASTM F138-13a - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Oct-2013
• Refers: ASTM F67-13 - Standard Specification for Unalloyed Titanium, for Surgical Implant Applications (UNS R50250, UNS R50400, UNS R50550, UNS R50700)
• Effective Date: 01-Jun-2013
• Refers: ASTM F138-13 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-Apr-2013
• Refers: ASTM F75-12 - Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075)
• Effective Date: 15-May-2012
• Refers: ASTM F90-09 - Standard Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy for Surgical Implant Applications (UNS R30605)
• Effective Date: 01-Jun-2009
• Refers: ASTM F138-08 - Standard Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 01-May-2008
• Refers: ASTM F90-07 - Standard Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy for Surgical Implant Applications (UNS R30605)
• Effective Date: 15-May-2007
• Refers: ASTM F640-07 - Standard Test Methods for Determining Radiopacity for Medical Use
• Effective Date: 01-Mar-2007
• Refers: ASTM F75-07 - Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075)
• Effective Date: 01-Jan-2007
• Refers: ASTM F67-06 - Standard Specification for Unalloyed Titanium, for Surgical Implant Applications (UNS R50250, UNS R50400, UNS R50550, UNS R50700)
• Effective Date: 01-Jun-2006
• Refers: ASTM F138-03 - Standard Specification for Wrought 18 Chromium-14 Nickel-2.5 Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 10-Jun-2003
• Refers: ASTM F138-97 - Standard Specification for Wrought 18 Chromium-14 Nickel-2.5 Molybdenum Stainless Steel Bar and Wire for Surgical Implants (UNS S31673)
• Effective Date: 10-Jun-2003
• Refers: ASTM F75-01 - Standard Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS R30075)
• Effective Date: 10-Dec-2001

Overview

ASTM F647-22: Standard Practice for Evaluating and Specifying Implantable Shunt Assemblies for Neurosurgical Application is an internationally recognized guideline published by ASTM International. This standard sets forth minimum requirements for the safety, efficacy, evaluation, and specification of implantable shunts used in neurosurgical procedures, particularly for the management of hydrocephalus and related conditions. It provides a comprehensive framework and common terminology for manufacturers, regulatory bodies, and clinicians, ensuring that implantable shunt assemblies meet essential quality, safety, and performance benchmarks before their use in patients.

Key Topics

• Scope of Application: Covers both temporary and permanent implantable shunt devices used for external drainage or internal diversion of cerebrospinal fluid (CSF) from the central nervous system to appropriate delivery sites.
• Device Components: Addresses catheters (atrial, peritoneal, ventricular), connectors, accessory devices (antisiphon devices, reservoirs), valved catheters, and valves.
• Material Requirements: Specifies the standards for metals and polymeric materials, radiopacity, and biocompatibility to minimize risk and ensure long-term function.
• Mechanical Properties: Details requirements for surface finish, durability, assembly integrity, flexibility, and strength of components.
• Sterility and Packaging: Emphasizes validated sterilization processes, sterile packaging that maintains integrity, and labeling practices for traceability and safety.
• Radiopacity: Mandates visibility of shunt assemblies and components under X-ray using radiopaque markers, facilitating correct placement and post-implantation monitoring.
• MRI Compatibility: Addresses the risks associated with magnetizable materials and the need for proper labeling if such materials are present.

Applications

ASTM F647-22 is vital across multiple aspects of neurosurgical device lifecycle:

• Design and Manufacturing: Guides developers in selecting appropriate materials for use in cerebrospinal fluid shunts, and in designing components that meet stringent safety and performance requirements.
• Quality Assurance: Provides standardized test methods (such as pressure/flow evaluation and radiopacity assessment) ensuring shunts and accessories conform to defined mechanical and functional properties prior to market distribution.
• Regulatory Compliance: Facilitates compliance with international medical device regulations by offering clear criteria for packaging, labeling, traceability, and documentation.
• Clinical Practice: Assures neurosurgeons that shunt assemblies comply with established industry standards for sterility, MRI compatibility, and performance, reducing the risk of device failure or patient harm.
• Procurement and Evaluation: Helps purchasing agents and hospital administrators evaluate and specify products that meet globally accepted safety and quality benchmarks, improving patient outcomes and liability management.

Related Standards

ASTM F647-22 references and aligns with several other ASTM standards and international guidelines important to neurosurgical medical devices, including:

• ASTM F67: Specification for Unalloyed Titanium for Surgical Implant Applications
• ASTM F75: Specification for Cobalt-Chromium-Molybdenum Alloy Castings for Surgical Implants
• ASTM F90: Specification for Wrought Cobalt-Nickel-Based Alloys for Surgical Applications
• ASTM F138: Specification for Wrought Stainless Steels for Surgical Implants
• ASTM F640: Test Methods for Determining Radiopacity for Medical Use
• ISO 10993: Biological Evaluation of Medical Devices (for biocompatibility)
• United States Pharmacopeia (USP): For extractable materials and pyrogenicity

These related documents ensure comprehensive coverage of material specifications, mechanical properties, and biological safety, supporting a consistent approach to the development, evaluation, and clinical use of implantable neurosurgical shunt assemblies.

Keywords: ASTM F647-22, implantable shunt assemblies, neurosurgical devices, hydrocephalus shunt, CSF shunt, medical device standards, safety, efficacy, radiopacity, MRI compatibility, biocompatibility, packaging, labeling, sterility.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F647 − 22
Standard Practice for
Evaluating and Specifying Implantable Shunt Assemblies for
Neurosurgical Application
ThisstandardisissuedunderthefixeddesignationF647;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
A hydrocephalus shunt assembly is a one-way pressure-activated or flow-controlling device or
combination of devices intended to be surgically implanted in the body of a patient with
hydrocephalusanddesignedtodivertcerebrospinalfluid(CSF)fromfluidcompartmentsinthecentral
nervous system (CNS) (the cerebral ventricles or other site within the cerebrospinal fluid system) to
an internal delivery site (internal shunt) in another part of the body or an external collection site
(external shunt), for the purpose of relieving elevated intracranial pressure or CSF volume.
A hydrocephalus shunt system typically consists of three basic elements: (1) an inflow (proximal)
catheter, which drains CSF from the ventricular system, lumbar subarachnoid space, or extraventricu-
lar structure and transmits it to (2) an arrangement of one or more valves which regulate(s) the
differential pressure or controls flow through the system, and (3) an outflow (distal) catheter which
drains CSF into the cardiovascular system via the peritoneal cavity, heart, or other suitable drainage
site. In addition, specialized accessory devices such as reservoirs, antisiphon devices, and on-off
valves and filters are added at the discretion of the physician to modify performance or adapt the basic
system to the specialized needs of the patient.
Because of the considerable length of time over which a shunt or component may be required to
function after implantation, it is felt that it should be type-tested to ensure its durability. It has not yet
been found feasible to specify a test method of durability testing, but a test method is proposed in
Appendix X1.
1. Scope 1.4 The following components that individually or in com-
bination comprise shunt assemblies are considered to be within
1.1 This practice covers requirements for the evaluation and
the scope of this practice: catheters (such as atrial, peritoneal,
specification of implantable shunts as related to resistance to
ventricular), connectors, implantable accessory devices (such
flow, direction of flow, materials, radiopacity, mechanical
as antisiphon devices and reservoirs), valved catheters, and
properties, finish, sterility, and labeling of shunt assemblies.
valves.
1.2 Devices to which this practice is applicable include, but
NOTE 1—The standards in Section 2 contain provisions that, through
arenotlimitedto,thosethataretemporarilyimplantedtoeffect
reference in this text, constitute provisions of this practice.At the time of
external drainage; or permanently implanted to effect shunting
publication, the editions indicated are valid. All standards are subject to
of fluid from a cerebral ventricle, a cyst, the subarachnoid
revision, and parties to agreements based on this practice are encouraged
space to the peritoneal cavity, the venous circulation, or some
to investigate the possibility of applying the most recent editions of the
standards indicated below. Devices or components, or both, whose
other suitable internal delivery site, and intracranial bypass.
structures are comparable to that outlined in these standards are accept-
1.3 Limitations—Although this practice includes a standard
able.
test method for the evaluation of pressure/flow characteristics
1.5 This standard does not purport to address all of the
of shunts or shunt components, it does not include specific
safety concerns, if any, associated with its use. It is the
pressure/flow requirements.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
ThispracticeisunderthejurisdictionofASTMCommitteeF04onMedicaland
mine the applicability of regulatory limitations prior to use.
Surgical Materials and Devices and is the direct responsibility of Subcommittee
F04.31 on Neurosurgical Standards.
1.6 This international standard was developed in accor-
Current edition approved Oct. 1, 2022. Published October 2022. Originally
dance with internationally recognized principles on standard-
approved in 1979. Last previous edition approved in 2014 as F647 – 94 (2014).
DOI: 10.1520/F0647-22. ization established in the Decision on Principles for the
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F647 − 22
Development of International Standards, Guides and Recom- 3.1.4 chambered valve—an element of a hydrocephalus
mendations issued by the World Trade Organization Technical shunt containing one or more valve mechanisms that is to
Barriers to Trade (TBT) Committee. facilitate selective flushing in the proximal or distal direction.
3.1.5 connector—a device intended for the joining and
2. Referenced Documents
fixation of implantable shunt components at operation.
2.1 ASTM Standards:
3.1.6 distal (outflow) catheter—that part of a hydrocephalus
F55 Specification for Stainless Steel Bar and Wire for
shuntassemblythatprovidesapassiveoutflowpathwayforthe
Surgical Implants (Withdrawn 1989)
diversion of fluid from a compartment of the central nervous
F67 Specification for Unalloyed Titanium, for Surgical Im-
system to the peritoneal cavity, venous circulation, or other
plant Applications (UNS R50250, UNS R50400, UNS
internal delivery site. The outflow catheter may or may not
R50550, UNS R50700)
contain a pressure/flow regulating device.
F75 Specification for Cobalt-28 Chromium-6 Molybdenum
3.1.7 flow-impedance device—those components of a shunt
Alloy Castings and Casting Alloy for Surgical Implants
assembly which, by virtue of their resistance properties,
(UNS R30075)
provide the principal means of controlling intracranial pressure
F90 Specification for Wrought Cobalt-20Chromium-
or flow of cerebrospinal fluid, or both. Flow-impedance de-
15Tungsten-10NickelAlloy for Surgical ImplantApplica-
vices include valved catheters and valves and the relevant
tions (UNS R30605)
constituent parts thereof.
F138 Specification for Wrought 18Chromium-14Nickel-
3.1.8 fluid compartment—the portion of the central nervous
2.5Molybdenum Stainless Steel Bar andWire for Surgical
system (CNS) including the ventricles and subdural space, and
Implants (UNS S31673)
extraventricular structures such as cysts and hygromas.
F469 Practice for Assessment of Compatibility of Nonpo-
rous Polymeric Materials for Surgical Implants with 3.1.9 functional range—the representative pressure/flow
Regard to Effect of Materials on Tissue (Withdrawn characteristics of a shunt or shunt element usually expressed in
1986) graphical form.
F604 Specification for Silicone Elastomers Used in Medical
3.1.10 hydrocephalus—the state of excessive accumulation
Applications (Withdrawn 2001)
of cerebrospinal fluid (CSF) within the ventricular system of
F640 Test Methods for Determining Radiopacity for Medi-
the head due to a disturbance of secretion, flow, or absorption,
cal Use
usually resulting in a pathological increase in intracranial
pressure (ICP).
NOTE2—AsuggestedmethodofdurabilitytestingisgiveninAppendix
X2.
3.1.11 hydrocephalus shunt—a one-way pressure-activated
or flow-controlling device or combination of devices intended
3. Terminology
to be surgically implanted in the body of a patient with
3.1 Definitions of Terms Specific to This Standard:
hydrocephalus and designed to divert cerebrospinal fluid from
3.1.1 antisiphon device—a device implanted to counteract
a fluid compartment in the central nervous system or CNS (the
the affects of the hydrostatic column of the outflow catheter.
cerebral ventricles or other site within the cerebrospinal fluid
Thisistominimizethegravity(alsotermed“siphoning”)effect
system) to an internal delivery site in another part of the body
of a hydrostatic pressure that may be created by the elevation
(internal shunt) or an external collection site (external shunt),
of the proximal (inflow) catheter in relation to the distal
forthepurposeofrelievingelevatedintracranialpressure(ICP)
(outflow) catheter, thus preventing the excessive drainage of
or CSF volume.
CSF caused by gravity.
3.1.12 hydrocephalus shunt assembly—a complete hydro-
3.1.1.1 Discussion—The Committee adopted the terms si-
cephalus shunt comprising all the components necessary for
phon effect and antisiphon device for this practice because they
clinical use.
are used in the medical literature. However, such devices are
3.1.13 implantable accessory device—component intended
designed to counteract the effects of gravity on the fluid in the
to facilitate the treatment of hydrocephalus by: providing
distal catheter when the patient is standing.
access to the shunt (such as reservoirs, antechambers, flushing
3.1.2 batch—a quantity of material that consists of a homo-
devices); modifying the performance characteristics of the
geneous mixture of common ingredients or a quantity of
shunt (such as on/off and antisiphon devices); or reducing
devices processed and controlled as an integral production run.
hazards attendant to the presence of the shunt assembly (such
3.1.3 calibration—the act of fixing, checking, or correcting as in-line filters).
on a schedule, the accuracy and precision of a measuring
3.1.14 implantable external drainage catheter—that ele-
instrument and maintaining records of these activities.
ment of an external drainage device which provides access to
a fluid compartment of the central nervous system.
2 3.1.15 kit—a number of components in a common package
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
to be used for a single purpose on the same occasion.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
3.1.16 magnetizable—a metal that has the capacity to ac-
the ASTM website.
quire magnetic properties of sufficient force to become dan-
The last approved version of this historical standard is referenced on
www.astm.org. gerous due to movement or thermal effects, or both, or to
F647 − 22
degrade the MRI image to the point of making it diagnostically and not modified during a surgical procedure (for example, the
or therapeutically useless.Ashunt system that is magnetizable site where the valve is chemically bonded or mechanically
is not MRI-compatible. joined to tubing).
3.1.25 preimplantation test—a test that is performed on the
3.1.17 modifiable connection—aportionoftheshuntassem-
shunt assembly in the operating room prior to implantation.
bly in which components are intended to be modified by the
surgeonduringasurgicalprocedure(forexample,thelengthof
3.1.26 pressure/flow graph—a graphic representation of the
a tube can be adjusted to accommodate the height of the
composite performance characteristics of a population of flow
patient).
impedance devices.
3.1.18 multipiece hydrocephalus shunt assembly—a com- 3.1.27 production line bench flow test—a test method used
plete sterile, single-use hydrocephalus shunt, supplied either by the manufacturer to verify that the pressure/flow character-
istics of each individual flow impedance device conforms to its
assembled by the manufacturer or in kit form for assembly by
the physician typically consisting of an inflow catheter, functional range.
pressure-activatedorflow-controllingdeviceorcombinationof
3.1.28 proximal (inflow) catheter—that part of a hydro-
devices, and an outflow catheter with requisite connectors
cephalus shunt assembly that is inserted into the cerebral
required for assembly.
ventricles or any other site in the craniospinal axis to provide
access to a fluid compartment of the central nervous system
3.1.19 nominal category—thegenericperformancecategory
(for example, into a lateral ventricle) and therefore constitutes
of the pressure/flow characteristics of the shunt assembly
the inflow pathway for the diversion of fluid through a shunt
typicallydefinedas“low,”“medium,”“high,”etc.,thelimitsof
system.
which are defined by the manufacturer.
3.1.29 radiopacity—the X-ray absorption properties that
3.1.20 nonmodifiable connection—see preassembled con-
allow a shunt component to have clear and permanent visual-
nection.
ization fluoroscopically or on X-ray film after implantation.
3.1.21 one-piece hydrocephalus shunt assembly—complete
(See Annex A1.)
sterile, single-use hydrocephalus shunt consisting of an inflow
3.1.30 referee test method—the methods in the published
catheter integral with a pressure-activated or flow-controlling
standard for the device. The method and the corresponding
device or combination of devices and an integral outflow
requirements will be invoked when the performance of the
catheter.
medical device will be questioned. The manufacturer need not
3.1.22 on-off device—an accessory component specifically
use this referee test method in the usual inspection and quality
designed to permit alternate opening and closing of the shunt
control.
system upon external activation.
3.1.31 reflux—a flow of fluid within a hydrocephalus shunt
3.1.23 packaging—the protective wrapping of shunt sys- towards the cerebral ventricles or cerebrospinal fluid system.
tems or components:
3.1.32 shunt, v—to drain CSF from the CNS.
3.1.23.1 inner container—the packaging that is in direct
3.1.33 shunt assembly—any device or combination of de-
contact with the implant.
vices that functions to divert CSF from a fluid compartment of
the central nervous system to an internal delivery site (internal
3.1.23.2 multiple pack—a pack containing a number of unit
shunt) or an external collection site (external shunt).
packs.
3.1.34 shunt element—any component of a hydrocephalus
3.1.23.3 outer container or shelf container—a package,
shunt.
carton, or other container that may contain one or more unit
3.1.35 shunt filter—a device intended to remove particulate
containers. The packaging that envelopes the inner container
matter from the CSF before it passes through the shunt.
such that sterility and the integrity of that container is main-
tained.
3.1.36 sterile—in microbiology, free from all living organ-
isms; in practice, the condition of a product that has been
3.1.23.4 sterile pack—a pack intended to maintain the
subjected to a validated sterilization process and maintained in
sterility of the contents and comprising an inner and outer
this state by suitable protection.
container.
3.1.37 sterilized—term used to denote an object that has
3.1.23.5 transit container—a package, carton, or other con-
been subjected to a validated sterilization process.
tainer that may contain one or more unit containers used to
3.1.38 test specimen—a device or sample of devices repre-
protect the contents during shipping of the product from the
sentative of the population of devices.
manufacturer to the end user.
3.1.39 tip valve—an element of a hydrocephalus shunt
3.1.23.6 unit container—a package containing a single item
located at the distal catheter tip that controls pressure or
oracombinationofprocedure-relatedcomponentsorproducts.
establishes flow of cerebrospinal fluid and resists reflux of
3.1.23.7 unit pack—a pack containing a single unit or kit.
blood or other fluids into the shunt.
3.1.24 preassembled connection—a portion of the shunt 3.1.40 traceability reference—the number or other means of
assembly, the components of which are preassembled at the identification by which components can be traced to a specific
time of manufacture and are intended to be permanently fixed manufacturing lot or batch.
F647 − 22
3.1.41 unit—individual device(s) or object(s) defined in the 6.1.1 Surface Finish—When examined with normal or cor-
relevant product standard or regulation. rected vision at a distance of 300 to 450 mm and at an
illuminance of 2150 6 215 lx, the surface of all implantable
3.1.42 use-by date—a date that may be established by the
shunts and components of a shunt assembly that have passed
manufacturer after which the device is not to be implanted.
through all stages of manufacture, including sterilization, shall
3.1.43 valve—an element of a hydrocephalus shunt assem-
be clean, smooth, and free from surface irregularities, flash,
bly that functions as a major resistance to the CSF flow, thus
molding and extrusion defects, and extraneous particles that
controlling the relationship between pressure and flow of
would be expected to compromise the function of the device.
cerebrospinal fluid, and resists reflux of blood or other fluids
6.1.2 Radiopacity—When tested by the method described in
into the shunt assembly. In contrast to a valved catheter, it does
AnnexA1, all integral components and connectors of the shunt
not provide a significant portion of tubing for the fluid
or component shall be radiopaque or shall carry radiopaque
pathway.
markers, so as to allow their visualization by X-rays. Compos-
3.1.44 valved catheter—an assembly or element of a shunt
ite structures or assemblies may contain radiolucent portions if
which provides a pathway for diversion of CSF to an internal
surrounding or overlay material clearly identifies the location
delivery site and contains one or more valves, typically, a tip
of nonradiopaque elements and enables any discontinuities to
valve, and a significant portion of tubing for the fluid pathway.
be readily apparent.
6.1.3 Magnetic Resonance Imaging (MRI) Compatibility—
4. Significance and Use
Imaging and investigative techniques such as nuclear magnetic
4.1 This practice provides minimum requirements for the
resonance (NMR) and magnetic resonance imaging (MRI)
ensurance of safety and efficacy. It provides a common
involve placing the patient in a strong magnetic field.This may
language whereby the function of these surgical implants is
result in severe stresses on magnetizable materials (that is, a
described.
metal that has the capacity to acquire magnetic properties of
sufficient force to become dangerous due to movement or
5. Materials
thermal effects, or both, or to degrade an MRI image to the
5.1 Metals used in the fabrication of implantable shunt
point of making it diagnostically or therapeutically useless),
components shall conform to specifications as referenced in
even moving them through tissues. Magnetizable materials
2.1.
should be avoided if possible in hydrocephalus shunts but, if
5.2 All polymeric materials shall have total levels of ex-
used, a suitable warning shall be included in the product
tractable antimony, arsenic, bismuth, copper, lead, cadmium, labeling (see 6.4.2.6).
mercury, and tin not exceeding 10 ppm (each), when tested by
6.1.4 Biological Properties—Intheabsenceofatestmethod
conventional methods of extraction and microanalysis con-
for freedom from biological hazard, it is not possible to lay
forming to the United States Pharmacopeia (USP), spectro-
down requirements for toxicity or biocompatibility in this
graphic analysis, or other machine methods that are proven
standard. It is essential that such tests are carried out on the
reliable. The shunt manufacturer shall use Specification F604
initial formulation of materials and whenever there is a major
to provide guidance in the selection of silicone elastomeric
change in the formulation or processing, or both.
materials appropriate for shunt application.
6.1.5 Specific guidance on the biological properties of
5.3 Biocompatibility (Polymeric Materials): materials is given in Appendix X2.
5.3.1 Each polymeric formulation shall be shown to pro-
6.2 Mechanical Properties:
duce an acceptable level of tissue reaction by cell culture,
6.2.1 Where applicable, shunt assemblies, valved catheters,
hemolysis (USP), pyrogenicity (USP), extraction and intracu-
valves, and catheters with integral valves shall be evaluated for
taneousinjectioninrabbits(USP),andbyPracticeF469orany
security of assembly and absence of assembly leakage and for
comparable procedures.
tensilestrength.Theyshallbesufficientlystrongandflexibleas
5.3.2 Each batch of polymeric material shall be biocompat-
to permit manipulation and be resistant to stresses ordinarily
ible when tested by cell culture or seven-day rabbit implant
associated with placement and use.
(USP).
6.2.2 For any given shunt component and where
5.4 Interfacingsurfacesofmatedshuntcomponentsmustbe
appropriate, the manufacturer shall subject device(s) (test
of the same material composition or recognized compatible
specimens) to testing of those mechanical properties that are
materials (for example, connector-catheter interfacing materi-
pertinent to in vivo performance.
als).
6.2.3 Testing shall be performed on a finished product(s)
5.5 Guidance for selection of materials is contained in
selected in accordance with the manufacturer’s usual quality
Appendix X2.
assurance program.
6.2.3.1 The manufacturer shall specifically ensure the secu-
6. General Requirements for Complete Shunts and
rity of assembly of nonmodifiable junction sites, by subjecting
Components
a test specimen of the assembly to an applied load. Nonmodi-
6.1 Physical Requirements:
fiable junctions shall be as strong as modifiable junctions
(assembled according to the manufacturer’s instructions for
Journal of Pharmacological Science, Vol 54, No. 156, 1965. use) when tested in a similar manner.
F647 − 22
6.2.3.2 The manufacturer shall specifically ensure absence 6.4.2.5 If appropriate, the word “RADIOPAQUE” or
of assembly leakage at nonmodifiable junction sites, by sub- equivalent;
jecting a test sample of the assembly to an applied pressure of 6.4.2.6 If appropriate, a warning that the contents contain
1000 mm H O for 5 min. Nonmodifiable junctions shall have magnetizable materials (including notation on patient ID card);
the same properties to resist leakage as modifiable junctions
6.4.2.7 If the contents may be resterilized, full instructions
(assembled according to the manufacturer’s instructions for for resterilization, indicating the recommended maximum
use) when tested in a similar manner.
number of sterilization cycles;
6.2.3.3 The manufacturer shall specifically ensure that test 6.4.2.8 A warning against use of the contents if the unit
specimens shall be tested by the method used or recommended
container is open or damaged;
after sterilization if the shunt is packaged and sold after 6.4.2.9 Directions for opening the container and aseptic
sterilization.
presentation of the contents;
6.2.3.4 Particulars of the test methodology used by each
6.4.2.10 In the case of contents having a determined shelf
manufacturer, including test apparatus, etc., shall be docu-
life, the “use before” date (year) beyond which the contents
mented and retained for a minimum of 25 years for perma- should not be implanted;
nently implanted products and in no case less than two years
6.4.2.11 The words “SINGLE USE” or equivalent phrase;
from the date of release for commercial distribution by the
6.4.2.12 Any special instructions for storage of the unit
manufacturer.
container.
6.4.3 Shelf Container—The shelf container shall be either
6.3 Packaging:
wholly or partially transparent so that the unit container
6.3.1 Unit Container:
markings are visible; or labeled or marked with the following
6.3.1.1 Each shunt or component shall be individually
information:
packaged and sealed in a unit container, the materials of which
6.4.3.1 Adescription of the contents, as specified in 6.1.2 or
shall be non-fibrous and lint-free.
6.1.3 (as appropriate), and number of contents;
6.3.1.2 The construction of the unit container shall be such
6.4.3.2 The words “STERILE” and “NONPYROGENIC”;
that once it has been opened, this fact shall be evident.
6.4.3.3 The name and address of the manufacturer or
NOTE 3—The packaging material should have no deleterious effects on
supplier;
the contents of the unit container. The unit container should provide
6.4.3.4 Thebatchnumberanddateofmanufacture(yearand
adequate physical protection to the contents under normal conditions of
month) or a batch number from which the date of manufacture
handling, transit, and storage, and be constructed so that, once opened, it
cannot be easily resealed.
can be determined;
6.4.3.5 Any special instructions for storage; and
6.3.1.3 The unit container should maintain the sterility of
6.4.3.6 In the case of contents having a determined shelf
the contents and be constructed so as to facilitate the aseptic
life, the expiry date (year) beyond which the contents should
presentation of the device for use.
not be implanted.
6.3.1.4 Ifshuntsorcathetersarenotpackagedinthestraight
configuration, they should be packaged in such a manner that
6.5 Additional Requirements for Complete Shunts, Valves,
no permanent deformation is produced.
and Catheters with Integral Valves and Components:
6.3.2 Shelf Containers—Oneoranumberofunitcontainers,
6.5.1 Type and Size Designation—The type and size of the
each containing the same model of shunt or component, shall
shunt shall be designated by means of the following informa-
be packaged in a shelf container.
tion:
6.5.1.1 The function of the valve/catheter (for example,
NOTE 4—The shelf container should provide protection of the contents
undernormalconditionsofhandling,transit,andstorage.Oneoranumber inflow, outflow, etc.);
of shelf containers may additionally be packaged in an outer or transit
6.5.1.2 The nominal operating characteristics of valve (for
container.
example, high, medium, low);
6.4 Labeling, Packaging, and Sterility:
6.5.1.3 The overall nominal length of component expressed
6.4.1 Shunts and Components:
in millimetres or centimetres, stating the unit used;
6.5.1.4 The nominal inside and outside diameters of the
NOTE5—Itisrecommendedthatshuntsandcomponentsthroughwhich
tubular portions of the component at connection point, ex-
the fluid flow is unidirectional shall be marked to indicate the intended
direction of flow (for example, by means of an arrow) using a method that
pressed in millimetres.
is visible and obvious to the implanting surgeon.
6.5.2 Connectors—If additional connectors are supplied for
6.4.2 Unit Container—The following information shall be use in conjunction with valves and catheters with integral
marked on the unit container or given in a leaflet or insert: valves, the dimensions of the connectors shall be such that the
6.4.2.1 The particular information specified in 6.1.2 and pressure and flow characteristics of the shunt with the connec-
6.1.3, as appropriate; tions in place shall not, when tested in accordance with Annex
6.4.2.2 The words “STERILE” and “NONPYROGENIC”; A2, differ by more than 10 % from the values determined for
6.4.2.3 The name or registered trademark, or both, of the the shunt without the additional connectors in place.
manufacturer or supplier; 6.5.3 Resistance Properties—Theresultsforapreassembled
6.4.2.4 Thebatchnumberanddateofmanufacture(yearand shunt or a shunt sold as a kit, a valve, or a catheter with valves,
month) or a batch number from which the date of manufacture when tested in accordance with Annex A2, shall lie within a
can be determined; specifiedconfidenceintervalofthefunctionalrangeofthetype
F647 − 22
of component stated by the manufacturer in accordance with 6.7.1.2 Astatementwhethertheshunthasbeentestedbythe
published instructions for use. manufacturer and the suitable tests, if any, the manufacturer
6.5.3.1 The manufacturer shall be given the choice between recommends to the surgeon to determine whether or not the
providing pressure/flow characteristics of the assembled shunt shunt falls in a specific band range;
and providing pressure/flow characteristics of each component 6.7.1.3 A statement of or a code for the nominal flow
in the kit, provided the manufacturer has obtained adequate resistance of the valve in accordance with Annex A2 or other
data demonstrating the additive resistive effects of various manufacturer’s criteria.
shunt components, and the manufacturer properly explains 6.7.2 Accompanying Documentation—Eachcompleteshunt,
these additive properties in the accompanying documentation. valve,catheterwithintegralvalve,andcomponentssuppliedas
6.5.3.2 Complete shunts, valved shunt assembly, or integral separate items shall be accompanied by documentation that
valves shall be tested in accordance with Annex A2. includes the following information:
6.5.3.3 The pressure/flow properties of a complete shunt, 6.7.2.1 Adescription of the contents, including the type and
valve, or catheter with integral valve shall be such to provide size in accordance with 6.4;
resistance to flow of cerebrospinal fluid through the shunt, and 6.7.2.2 Instructions for assembly of the shunt or use of the
to provide unidirectional flow in accordance with Annex A2. valve, catheter with integral valve, and component(s) in the
6.5.3.4 Pressure/flow curves shall be plotted with flow rate assembly of a shunt system;
on the horizontal axis and pressure on th
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F647 − 94 (Reapproved 2014) F647 − 22
Standard Practice for
Evaluating and Specifying Implantable Shunt Assemblies for
Neurosurgical Application
This standard is issued under the fixed designation F647; the number immediately following the designation indicates the year of original
adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
A hydrocephalus shunt assembly is a one-way pressure-activated or flow-controlling device or
combination of devices intended to be surgically implanted in the body of a patient with
hydrocephalus and designed to divert cerebrospinal fluid (CSF) from fluid compartments in the central
nervous system (CNS) (the cerebral ventricles or other site within the cerebrospinal fluid system) to
an internal delivery site (internal shunt) in another part of the body or an external collection site
(external shunt), for the purpose of relieving elevated intracranial pressure or CSF volume.
A hydrocephalus shunt system typically consists of three basic elements: (1) an inflow (proximal)
catheter, which drains CSF from the ventricular system, lumbar subarachnoid space, or extraventricu-
lar structure and transmits it to (2) an arrangement of one or more valves which regulate(s) the
differential pressure or controls flow through the system, and (3) an outflow (distal) catheter which
drains CSF into the cardiovascular system via the peritoneal cavity, heart, or other suitable drainage
site. In addition, specialized accessory devices such as reservoirs, antisiphon devices, and on-off
valves and filters are added at the discretion of the physician to modify performance or adapt the basic
system to the specialized needs of the patient.
Because of the considerable length of time over which a shunt or component may be required to
function after implantation, it is felt that it should be type-tested to ensure its durability. It has not yet
been found feasible to specify a test method of durability testing, but a test method is proposed in
Appendix X1.
1. Scope
1.1 This practice covers requirements for the evaluation and specification of implantable shunts as related to resistance to flow,
direction of flow, materials, radiopacity, mechanical properties, finish, sterility, and labeling of shunt assemblies.
1.2 Devices to which this practice is applicable include, but are not limited to, those that are temporarily implanted to effect
external drainage; or permanently implanted to effect shunting of fluid from a cerebral ventricle, a cyst, the subarachnoid space
to the peritoneal cavity, the venous circulation, or some other suitable internal delivery site, and intracranial bypass.
1.3 Limitations—Although this practice includes a standard test method for the evaluation of pressure/flow characteristics of
shunts or shunt components, it does not include specific pressure/flow requirements.
This practice is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is the direct responsibility of Subcommittee F04.31
on Neurosurgical Standards.
Current edition approved Nov. 15, 2014Oct. 1, 2022. Published November 2014October 2022. Originally approved in 1979. Last previous edition approved in 20062014
as F647 – 94 (2006).(2014). DOI: 10.1520/F0647-94R14.10.1520/F0647-22.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F647 − 22
1.4 The following components,components that individually or in combination comprise shunt assemblies,assemblies are
considered to be within the scope of this practice: catheters (such as atrial, peritoneal, ventricular), connectors, implantable
accessory devices (such as antisiphon devices and reservoirs), valved catheters, and valves.
NOTE 1—The standards in Section 2 contain provisions that, through reference in this text, constitute provisions of this practice. At the time of publication,
the editions indicated are valid. All standards are subject to revision, and parties to agreements based on this practice are encouraged to investigate the
possibility of applying the most recent editions of the standards indicated below. Devices or components, or both, whose structures are comparable to
that outlined in these standards are acceptable.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
NOTE 1—The following standards contain provisions that, through reference in this text, constitute provisions of this practice. At the time of publication,
the editions indicated are valid. All standards are subject to revision, and parties to agreements based on this practice are encouraged to investigate the
possibility of applying the most recent editions of the standards indicated below. Devices or components, or both, whose structures are comparable to
that outlined in these standards are acceptable.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
F55 Specification for Stainless Steel Bar and Wire for Surgical Implants (Withdrawn 1989)
F56 Specification for Stainless Steel Sheet and Strip for Surgical Implants (Withdrawn 1989)
F67 Specification for Unalloyed Titanium, for Surgical Implant Applications (UNS R50250, UNS R50400, UNS R50550, UNS
R50700)
F75 Specification for Cobalt-28 Chromium-6 Molybdenum Alloy Castings and Casting Alloy for Surgical Implants (UNS
R30075)
F90 Specification for Wrought Cobalt-20Chromium-15Tungsten-10Nickel Alloy for Surgical Implant Applications (UNS
R30605)
F138 Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Bar and Wire for Surgical Implants
(UNS S31673)
F469 Practice for Assessment of Compatibility of Nonporous Polymeric Materials for Surgical Implants with Regard to Effect
of Materials on Tissue (Withdrawn 1986)
F604 Specification for Silicone Elastomers Used in Medical Applications (Withdrawn 2001)
F640 Test Methods for Determining Radiopacity for Medical Use
F897 Test Method for Measuring Fretting Corrosion of Osteosynthesis Plates and Screws
NOTE 2—A suggested method of durability testing is given in Appendix X2.
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 antisiphon device—a device implanted to counteract the affects of the hydrostatic column of the outflow catheter. This is to
minimize the gravity (also termed “siphoning”) effect of a hydrostatic pressure that may be created by the elevation of the proximal
(inflow) catheter in relation to the distal (outflow) catheter, thus preventing the excessive drainage of CSF caused by gravity.
3.1.1.1 Discussion—
The Committee adopted the terms siphon effect and antisiphon device for this practice because they are used in the medical
literature. However, such devices are designed to counteract the effects of gravity on the fluid in the distal catheter when the patient
is standing.
3.1.2 batch—a quantity of material that consists of a homogeneous mixture of common ingredients or a quantity of devices
processed and controlled as an integral production run.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
F647 − 22
3.1.3 calibration—the act of fixing, checking, or correcting on a schedule, the accuracy and precision of a measuring instrument
and maintaining records of these activities.
3.1.4 chambered valve—an element of a hydrocephalus shunt containing one or more valve mechanisms that is to facilitate
selective flushing in the proximal or distal direction.
3.1.5 connector—a device intended for the joining and fixation of implantable shunt components at operation.
3.1.6 distal (outflow) catheter—that part of a hydrocephalus shunt assembly that provides a passive outflow pathway for the
diversion of fluid from a compartment of the central nervous system to the peritoneal cavity, venous circulation, or other internal
delivery site. The outflow catheter may or may not contain a pressure/flow regulating device.
3.1.7 flow-impedance device—those components of a shunt assembly which, by virtue of their resistance properties, provide the
principal means of controlling intracranial pressure or flow of cerebrospinal fluid, or both. Flow-impedance devices include valved
catheters and valves and the relevant constituent parts thereof.
3.1.8 fluid compartment—the portion of the central nervous system (CNS) including the ventricles and subdural space, and
extraventricular structures such as cysts and hygromas.
3.1.9 functional range—the representative pressure/flow characteristics of a shunt or shunt element usually expressed in graphical
form.
3.1.10 hydrocephalus—the state of excessive accumulation of cerebrospinal fluid (CSF) within the ventricular system of the head
due to a disturbance of secretion, flow, or absorption, usually resulting in a pathological increase in intracranial pressure (ICP).
3.1.11 hydrocephalus shunt—a one-way pressure-activated or flow-controlling device or combination of devices intended to be
surgically implanted in the body of a patient with hydrocephalus and designed to divert cerebrospinal fluid from a fluid
compartment in the central nervous system or CNS (the cerebral ventricles or other site within the cerebrospinal fluid system) to
an internal delivery site in another part of the body (internal shunt) or an external collection site (external shunt), for the purpose
of relieving elevated intracranial pressure (ICP) or CSF volume.
3.1.12 hydrocephalus shunt assembly—a complete hydrocephalus shunt comprising all the components necessary for clinical use.
3.1.13 implantable accessory device—component intended to facilitate the treatment of hydrocephalus by: providing access to the
shunt (such as reservoirs, antechambers, flushing devices) or; devices); modifying the performance characteristics of the shunt
(such as on/off and antisiphon devices) or;devices); or reducing hazards attendant to the presence of the shunt assembly (such as
in-line filters).
3.1.14 implantable external drainage catheter—that element of an external drainage device which provides access to a fluid
compartment of the central nervous system.
3.1.15 kit—a number of components in a common package to be used for a single purpose on the same occasion.
3.1.16 magnetizable—a metal that has the capacity to acquire magnetic properties of sufficient force to become dangerous due to
movement or thermal effects, or both, or to degrade the MRI image to the point of making it diagnostically or therapeutically
useless. A shunt system that is magnetizable is not MRI-compatible.
3.1.17 modifiable connection—a portion of the shunt assembly in which components are intended to be modified by the surgeon
during a surgical procedure (for example, the length of a tube can be adjusted to accommodate the height of the patient).
3.1.18 multipiece hydrocephalus shunt assembly—a complete sterile, single-use hydrocephalus shunt, supplied either assembled
by the manufacturer or in kit form for assembly by the physician typically consisting of an inflow catheter, pressure-activated or
flow-controlling device or combination of devices, and an outflow catheter with requisite connectors required for assembly.
F647 − 22
3.1.19 nominal category—the generic performance category of the pressure/flow characteristics of the shunt assembly typically
defined as “low,”“ medium,”“low,” “medium,” “high,” etc., the limits of which are defined by the manufacturer.
3.1.20 nonmodifiable connection—see preassembled connection.
3.1.21 one-piece hydrocephalus shunt assembly—complete sterile, single-use hydrocephalus shunt consisting of an inflow catheter
integral with a pressure-activated or flow-controlling device or combination of devices and an integral outflow catheter.
3.1.22 on-off device—an accessory component specifically designed to permit alternate opening and closing of the shunt system
upon external activation.
3.1.23 packaging—the protective wrapping of shunt systems or components:
3.1.23.1 inner container—the packaging that is in direct contact with the implant.
3.1.23.2 multiple pack—a pack containing a number of unit packs.
3.1.23.3 outer container or shelf container—a package, carton, or other container that may contain one or more unit containers.
The packaging that envelopes the inner container such that sterility and the integrity of that container is maintained.
3.1.23.4 sterile pack—a pack intended to maintain the sterility of the contents and comprising an inner and outer container.
3.1.23.5 transit container—a package, carton, or other container that may contain one or more unit containers used to protect
the contents during shipping of the product from the manufacturer to the end user.
3.1.23.6 unit container—a package containing a single item or a combination of procedure-related components or products.
3.1.23.7 unit pack—a pack containing a single unit or kit.
3.1.24 preassembled connection—a portion of the shunt assembly, the components of which are preassembled at the time of
manufacture and are intended to be permanently fixed and not modified during a surgical procedure (for example, the site where
the valve is chemically bonded or mechanically joined to tubing).
3.1.25 preimplantation test—a test that is performed on the shunt assembly in the operating room prior to implantation.
3.1.26 pressure/flow graph—a graphic representation of the composite performance characteristics of a population of flow
impedance devices.
3.1.27 production line bench flow test—a test method used by the manufacturer to verify that the pressure/flow characteristics of
each individual flow impedance device conforms to its functional range.
3.1.28 proximal (inflow) catheter—that part of a hydrocephalus shunt assembly that is inserted into the cerebral ventricles or any
other site in the craniospinal axis to provide access to a fluid compartment of the central nervous system (for example, into a lateral
ventricle) and therefore constitutes the inflow pathway for the diversion of fluid through a shunt system.
3.1.29 radiopacity—the X-ray absorption properties that allow a shunt component to have clear and permanent visualization
fluoroscopically or on X-ray film after implantation. (See Annex A1).)
3.1.30 referee test method—the methods in the published standard for the device. The method and the corresponding requirements
will be invoked when the performance of the medical device will be questioned. The manufacturer need not use this referee test
method in the usual inspection and quality control.
3.1.31 reflux—a flow of fluid within a hydrocephalus shunt towards the cerebral ventricles or cerebrospinal fluid system.
3.1.32 shunt, v—to drain CSF from the CNS.
3.1.33 shunt assembly—any device or combination of devices that functions to divert CSF from a fluid compartment of the central
nervous system to an internal delivery site (internal shunt) or an external collection site (external shunt).
F647 − 22
3.1.34 shunt element—any component of a hydrocephalus shunt.
3.1.35 shunt filter—a device intended to remove particulate matter from the CSF before it passes through the shunt.
3.1.36 sterile—in microbiology, free from all living organisms; in practice, the condition of a product that has been subjected to
a validated sterilization process and maintained in this state by suitable protection.
3.1.37 sterilized—term used to denote an object that has been subjected to a validated sterilization process.
3.1.38 test specimen—a device or sample of devices representative of the population of devices.
3.1.39 tip valve—an element of a hydrocephalus shunt located at the distal catheter tip that controls pressure or establishes flow
of cerebrospinal fluid and resists reflux of blood or other fluids into the shunt.
3.1.40 traceability reference—the number or other means of identification by which components can be traced to a specific
manufacturing lot or batch.
3.1.41 unit—individual device(s) or object(s) defined in the relevant product standard or regulation.
3.1.42 use by use-by date—a date that may be established by the manufacturer after which the device is not to be implanted.
3.1.43 valve—an element of a hydrocephalus shunt assembly that functions as a major resistance to the CSF flow, thus controlling
the relationship between pressure and flow of cerebrospinal fluid, and resists reflux of blood or other fluids into the shunt assembly.
In contrast to a valved catheter, it does not provide a significant portion of tubing for the fluid pathway.
3.1.44 valved catheter—an assembly or element of a shunt which provides a pathway for diversion of CSF to an internal delivery
site and contains one or more valves, typically, a tip valve, and a significant portion of tubing for the fluid pathway.
4. Significance and Use
4.1 This practice provides minimum requirements for the ensurance of safety and efficacy. It provides a common language
whereby the function of these surgical implants is described.
5. Materials
5.1 Metals used in the fabrication of implantable shunt components shall conform to specifications as referenced in 2.1.
5.2 All polymeric materials shall have total levels of extractable antimony, arsenic, bismuth, copper, lead, cadmium, mercury, and
tin not exceeding 10 ppm (each), when tested by conventional methods of extraction and microanalysis conforming to the United
States Pharmacopeia (USP), spectrographic analysis, or other machine methods that are proven reliable. The shunt manufacturer
shall use ClassificationSpecification F604 to provide guidance in the selection of silicone elastomeric materials appropriate for
shunt application.
5.3 Biocompatibility (Polymeric Materials):
5.3.1 Each polymeric formulation shall be shown to produce an acceptable level of tissue reaction by cell culture, hemolysis
(USP), pyrogenicity (USP), extraction and intracutaneous injection in rabbits (USP)), and by Practice F469 or any comparable
procedures.
5.3.2 Each batch of polymeric material shall be biocompatible when tested by cell culture or seven-day rabbit implant (USP).
Journal of Pharmacological Science, Vol 54, No. 156, 1965.
F647 − 22
5.4 Interfacing surfaces of mated shunt components must be of the same material composition or recognized compatible materials
(for example, connector-catheter interfacing materials).
5.5 Guidance for selection of materials is contained in Appendix X2.
6. General Requirements for Complete Shunts and Components
6.1 Physical Requirements:
6.1.1 Surface Finish—When examined with normal or corrected vision at a distance of 300 to 450 mm and at an illuminance of
2150 6 215 lx, the surface of all implantable shunts and components of a shunt assembly that have passed through all stages of
manufacture, including sterilization, shall be clean, smooth, and free from surface irregularities, flash, molding and extrusion
defects, and extraneous particles that would be expected to compromise the function of the device.
6.1.2 Radiopacity—When tested by the method described in Annex Annex A1, all integral components and connectors of the shunt
or component shall be radiopaque or shall carry radiopaque markers, so as to allow their visualization by X-rays. Composite
structures or assemblies may contain radiolucent portions if surrounding or overlay material clearly identifies the location of
nonradiopaque elements and enables any discontinuities to be readily apparent.
6.1.3 Magnetic Resonance Imaging (MRI) Compatibility—Imaging and investigative techniques such as nuclear magnetic
resonance (NMR) (magnetic and magnetic resonance imaging (MRI))(MRI) involve placing the patient in a strong magnetic field.
This may result in severe stresses on magnetizable materials (that is, a metal that has the capacity to acquire magnetic properties
of sufficient force to become dangerous due to movement or thermal effects, or both, or to degrade an MRI image to the point of
making it diagnostically or therapeutically useless), even moving them through tissues. Magnetizable materials should be avoided
if possible in hydrocephalus shunts but, if used, a suitable warning shall be included in the product labellinglabeling (see 6.4.2.6).
6.1.4 Biological Properties—In the absence of a test method for freedom from biological hazard, it is not possible to lay down
requirements for toxicity or biocompatibility in this Standard.standard. It is essential that such tests are carried out on the initial
formulation of materials and whenever there is a major change in the formulation or processing, or both.
6.1.5 Specific guidance on the biological properties of materials is given in Appendix X2.
6.2 Mechanical Properties:
6.2.1 Where applicable, shunt assemblies, valved catheters, valves, and catheters with integral valves shall be evaluated for
security of assembly and absence of assembly leakage and for tensile strength. They shall be sufficiently strong and flexible as to
permit manipulation and be resistant to stresses ordinarily associated with placement and use.
6.2.2 For any given shunt component and,and where appropriate, the manufacturer shall subject device(s) (test specimens) to
testing of those mechanical properties that are pertinent to in vivo performance.
6.2.3 Testing shall be performed on a finished product(s) selected in accordance with the manufacturer’s usual quality assurance
program.
6.2.3.1 The manufacturer shall specifically ensure the security of assembly of nonmodifiable junction sites, by subjecting a test
specimen of the assembly to an applied load. Nonmodifiable junctions shall be as strong as modifiable junctions (assembled
according to the manufacturer’s instructions for use) when tested in a similar manner.
6.2.3.2 The manufacturer shall specifically ensure absence of assembly leakage (defined as the formation of two drops or 0.1 mL)
at nonmodifiable junction sites, by subjecting a test sample of the assembly to an applied pressure of 3001000 mm H O for 15
min. Nonmodifiable junctions shall have the same properties to resist leakage as modifiable junctions (assembled according to the
manufacturer’s instructions for use) when tested in a similar manner.
6.2.3.3 The manufacturer shall specifically ensure that test specimens shall be tested by the method used or recommended after
sterilization if the shunt is packaged and sold after sterilization.
F647 − 22
6.2.3.4 Particulars of the test methodology used by each manufacturer, including test apparatus, etc., shall be documented and
retained for a minimum of 25 years for permanently implanted products and in no case less than two years from the date of release
for commercial distribution by the manufacturer.
6.3 Packaging:
6.3.1 Unit Container:
6.3.1.1 Each shunt or component shall be individually packaged and sealed in a unit container, the materials of which shall be
non-fibrous and lint-free.
6.3.1.2 The construction of the unit container shall be such that once it has been opened, this fact shall be evident.
NOTE 3—The packaging material should have no deleterious effects on the contents of the unit container. The unit container should provide adequate
physical protection to the contents under normal conditions of handling, transit, and storage, and be constructed so that, once opened, it cannot be easily
resealed.
6.3.1.3 The unit container should maintain the sterility of the contents and be constructed so as to facilitate the aseptic presentation
of the device for use.
6.3.1.4 If shunts or catheters are not packaged in the straight configuration, they should be packaged in such a manner that no
permanent deformation is produced.
6.3.2 Shelf Containers—One or a number of unit containers, each containing the same model of shunt or component, shall be
packaged in a shelf container.
NOTE 4—The shelf container should provide protection of the contents under normal conditions of handling, transit, and storage. One or a number of shelf
containers may additionally be packaged in an outer or transit container.
6.4 Labeling, Packaging, and Sterility:
6.4.1 Shunts and Components:
NOTE 5—It is recommended that shunts and components through which the fluid flow is uni-directionalunidirectional shall be marked to indicate the
intended direction of flow (for example, by means of an arrow) using a method that is visible and obvious to the implanting surgeon.
6.4.2 Unit Container—The following information shall be marked on the unit container or given in a leaflet or insert:
6.4.2.1 The particular information specified in 6.1.2 and 6.1.3, as appropriate;
6.4.2.2 The words “STERILE” and “NONPYROGENIC”;
6.4.2.3 The name or registered trademark, or both, of the manufacturer or supplier;
6.4.2.4 The batch number and date of manufacture (year and month) or a batch number from which the date of manufacture can
be determined.determined;
6.4.2.5 If appropriate, the word “RADIOPAQUE” or equivalent;
6.4.2.6 If appropriate, a warning that the contents contain magnetizable materials (including notation on patient ID card);
6.4.2.7 If the contents may be resterilized, full instructions for resterilization, indicating the recommended maximum number of
sterilization cycles;
6.4.2.8 A warning against use of the contents if the unit container is open or damaged;
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6.4.2.9 Directions for opening the container and aseptic presentation of the contents;
6.4.2.10 In the case of contents having a determined shelf-life, the Use Before Dateshelf life, the “use before” date (year) beyond
which the contents should not be implanted;
6.4.2.11 The words “SINGLE USE” or equivalent phrase;
6.4.2.12 Any special instructions for storage of the unit container.
6.4.3 Shelf Container—The shelf container shall be either wholly or partially transparent so that the unit container markings are
visible; or labelledlabeled or marked with the following information:
6.4.3.1 A description of the contents, as specified in clauses 6.1.2 or 6.1.3 (as appropriate), and number of contents,contents;
6.4.3.2 The words “STERILE” and “NONPYROGENIC,”“NONPYROGENIC”;
6.4.3.3 The name and address of the manufacturer or supplier,supplier;
6.4.3.4 The batch number and date of manufacture (year and month) or a batch number from which the date of manufacture can
be determined,determined;
6.4.3.5 Any special instructions for storage,storage; and
6.4.3.6 In the case of contents having a determined shelf-life, shelf life, the expiry date (year) beyond which the contents should
not be implanted.
6.5 Additional Requirements for Complete Shunts, Valves, and Catheters Withwith Integral Valves and Components:
6.5.1 Type and Size Designation—The type and size of the shunt shall be designated by means of the following information:
6.5.1.1 The function of the valve/catheter (for example, inflow, outflow, etc.);
6.5.1.2 The nominal operating characteristics of valve;valve (for example, high, medium, low)low);
6.5.1.3 The overall nominal length of component expressed in millimetres or centimetres, stating the unit used;
6.5.1.4 The nominal inside and outside diameters of the tubular portions of the component at connection point, expressed in
millimetres.
6.5.2 Connectors—If additional connectors are supplied for use in conjunction with valves and catheters with integral valves, the
dimensions of the connectors shall be such that the pressure and flow characteristics of the shunt with the connections in place shall
not, when tested in accordance with Annex A2, differ by more than 10 % from the values determined for the shunt without the
additional connectors in place.
6.5.3 Resistance Properties—The results for a preassembled shunt or a shunt sold as a kit, a valve, or a catheter with valves, when
tested in accordance with Annex A2, shall lie within a specified confidence interval of the functional range of the type of
component stated by the manufacturer in accordance with published instructions for use.
6.5.3.1 The manufacturer shall be given the choice between providing pressure/flow characteristics of the assembled shunt and
providing pressure/flow characteristics of each component in the kit, provided the manufacturer has obtained adequate data
demonstrating the additive resistive effects of various shunt components, and the manufacturer properly explains these additive
properties in the accompanying documentation.
6.5.3.2 Complete shunts, valved shunt assembly, or integral valves shall be tested in accordance with Annex A2.
6.5.3.3 The pressure/flow properties of a complete shunt, valve, or catheter with integral valve shall be such to provide resistance
to flow of cerebrospinal fluid through the shunt, and to provide unidirectional flow in accordance with Annex A2.
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6.5.3.4 Pressure/flow curves shall be plotted with flow rate on the horizontal axis and pressure on the vertical axis.
6.5.3.5 Evaluation of resistance properties shall be performed on a test specimen(s) prior to marketing and on a production-line
basis thereafter.
6.5.4 Freedom from Reflux—When tested in accordance with Annex A3, the complete shunt, valve, catheter with integral valve,
or component shall comply with the following requirements:
6.5.4.1 Chambered Valves—The meniscus shall remain static for at least 1 min at boththe test pressurespressure (see A3.5.1). The
meniscus shall remain static for at least 1 min (see A3.5.2). In the case of compressible valves, reflux shall not occur in the event
that the chamber is compressed.
6.5.4.2 Tip Valves—Tip valves shall not show the continued formation of drops (less than one drop0.04 cc per
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