SIST EN ISO 16671:2004
(Main)Ophthalmic implants - Irrigating solutions for ophthalmic surgery (ISO 16671:2003)
Ophthalmic implants - Irrigating solutions for ophthalmic surgery (ISO 16671:2003)
Specification of fundamental requirements for irrigating solutions used in intraocular surgery.
Ophthalmische Implantate - Spüllösungen für die ophthalmische Chirurgie (ISO 16671:2003)
Implants ophtalmiques - Solutions d'irrigation pour la chirurgie ophtalmique (ISO 16671:2003)
L'ISO 16671:2002 définit des exigences en matière de sécurité dans les performances prévues, les attributs de conception, les évaluations précliniques et cliniques, la stérilisation, l'emballage des produits, l'étiquetage des produits et les informations données par le fournisseur.
L'ISO 16671:2002 s'applique aux solutions d'irrigation ophtalmique utilisées en chirurgie ophtalmique. Elles n'ont pas de fonction immunologique, pharmacologique ou métabolique primaire.
Ophthalmic implants - Irrigating solutions for ophthalmic surgery (ISO 16671:2003)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 16671:2004
01-februar-2004
Ophthalmic implants - Irrigating solutions for ophthalmic surgery (ISO 16671:2003)
Ophthalmic implants - Irrigating solutions for ophthalmic surgery (ISO 16671:2003)
Ophthalmische Implantate - Spüllösungen für die ophthalmische Chirurgie (ISO
16671:2003)
Implants ophtalmiques - Solutions d'irrigation pour la chirurgie ophtalmique (ISO
16671:2003)
Ta slovenski standard je istoveten z: EN ISO 16671:2003
ICS:
11.040.70 Oftalmološka oprema Ophthalmic equipment
SIST EN ISO 16671:2004 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 16671:2004
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SIST EN ISO 16671:2004
EUROPEAN STANDARD
EN ISO 16671
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2003
ICS 11.040.70
English version
Ophthalmic implants - Irrigating solutions for ophthalmic surgery
(ISO 16671:2003)
Implants ophtalmiques - Solutions d'irrigation pour la Ophthalmische Implantate - Spüllösungen für die
chirurgie ophtalmique (ISO 16671:2003) ophthalmische Chirurgie (ISO 16671:2003)
This European Standard was approved by CEN on 3 November 2003.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36 B-1050 Brussels
© 2003 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 16671:2003 E
worldwide for CEN national Members.
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SIST EN ISO 16671:2004
EN ISO 16671:2003 (E)
Foreword
The text of ISO 16671:2003 has been prepared by Technical Committee ISO/TC 172 "Optics
and optical instruments" of the International Organization for Standardization (ISO) and has
been taken over as EN ISO 16671:2003 by Technical Committee CEN/TC 170 "Ophthalmic
optics", the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication
of an identical text or by endorsement, at the latest by May 2004, and conflicting national
standards shall be withdrawn at the latest by May 2004.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,
Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden,
Switzerland and the United Kingdom.
Endorsement notice
The text of ISO 16671:2003 has been approved by CEN as EN ISO 16671:2003 without any
modifications.
NOTE Normative references to International Standards are listed in Annex ZA (normative).
2
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SIST EN ISO 16671:2004
EN ISO 16671:2003 (E)
Annex ZA
(normative)
Normative references to international publications
with their relevant European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions
of any of these publications apply to this European Standard only when incorporated in it by
amendment or revision. For undated references the latest edition of the publication referred to
applies (including amendments).
NOTE Where an International Publication has been modified by common modifications,
indicated by (mod.), the relevant EN/HD applies.
Publication Year Title EN Year
ISO 10993-2 1992 Biological evaluation of medical EN ISO 10993-2 1998
devices - Part 2: Animal welfare
requirements
ISO 14155-1 2003 Clinical investigation of medical EN ISO 14155-1 2003
devices for human subjects - Part
1: General requirements
ISO 14155-2 2003 Clinical investigation of medical EN ISO 14155-2 2003
devices for human subjects - Part
2: Clinical investigation plans
ISO 14630 1997 Non-active surgical implants - EN ISO 14630 1997
General requirements
3
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SIST EN ISO 16671:2004
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SIST EN ISO 16671:2004
INTERNATIONAL ISO
STANDARD 16671
First edition
2003-05-01
Ophthalmic implants — Irrigating
solutions for ophthalmic surgery
Implants ophtalmiques — Solutions d'irrigation pour la chirurgie
ophtalmique
Reference number
ISO 16671:2003(E)
©
ISO 2003
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
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ii © ISO 2003 — All rights reserved
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
Contents Page
Foreword. iv
1 Scope. 1
2 Normative references. 1
3 Terms and definitions. 2
4 Intended performance. 2
5 Design attributes. 2
6 Design evaluation. 4
7 Sterilization. 5
8 Product stability. 6
9 Packaging. 6
10 Information supplied by the manufacturer. 6
Annex A (informative) Example of a suitable method for pH measurement and buffer capacity
determination . 8
Annex B (normative) Particulate contamination: visible particulates . 9
Annex C (informative) Light obscuration test method for particulate contamination: subvisible
particles. 10
Annex D (informative) Microscopic test method for particulate contamination: subvisible particles . 12
Annex E (normative) Intraocular irrigation test. 17
Annex F (informative) Clinical investigation. 18
Bibliography . 21
© ISO 2003 — All rights reserved iii
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 16671 was prepared by Technical Committee ISO/TC 172, Optics and optical instruments, Subcommittee
SC 7, Ophthalmic optics and instruments.
iv © ISO 2003 — All rights reserved
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SIST EN ISO 16671:2004
INTERNATIONAL STANDARD ISO 16671:2003(E)
Ophthalmic implants — Irrigating solutions for ophthalmic
surgery
1 Scope
This International Standard defines requirements with regards to safety for the intended performance, design
attributes, preclinical and clinical evaluation, sterilization, product packaging, product labelling and the
information supplied by the manufacturer.
This International Standard applies to ophthalmic irrigating solutions (OISs), used during ophthalmic surgery.
These solutions do not provide any primary immunological, pharmacological or metabolic function.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
1)
ISO 10993-1:— , Biological evaluation of medical devices — Part 1: Evaluation and testing
ISO 10993-2:1992, Biological evaluation of medical devices — Part 2: Animal welfare requirements
ISO 11607:2002, Packaging for terminally sterilized medical devices
ISO 13408-1:1998, Aseptic processing of health care products — Part 1: General requirements
ISO 14155-1, Clinical investigation of medical devices for human subjects — Part 1: General requirements
ISO 14155-2, Clinical investigation of medical devices for human subjects — Part 2: Clinical investigation
plans
ISO 14630:1997, Non-active surgical implants — General requirements
ISO 14971-1:1998, Medical devices — Risk management — Part 1: Application of risk analysis
ISO 15223:2000, Medical devices — Symbols to be used with medical device labels, labelling and information
to be supplied
EN 868-1:1997, Packaging materials and systems for medical devices which are to be sterilized — Part 1:
General requirements and test methods
EN 1041:1998, Information supplied by the manufacturer with medical devices
EN 12442-1:2000, Animal tissues and their derivatives utilized in the manufacture of medical devices —
Part 1: Analysis and management of risk
1) To be published. (Revision of ISO 10993-1:1997)
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
3 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply.
3.1
delivery system
sealed container in which the product is supplied and any additional components provided to introduce the
product into the eye
3.2
ophthalmic irrigating solution (OIS)
aqueous solution that is physiologically compatible with the intraocular environment and functions solely by
mechanical means
NOTE It does not provide any primary immunological, pharmacological or metabolic function.
4 Intended performance
The intended performance of the product shall be defined by the manufacturer. The intended performance
shall include the general requirements for the intended performance of non-active surgical implants outlined in
ISO 14630.
The extent to which the intended performance has been achieved shall be determined, taking into account
published standards, published clinical and scientific literature, validated test results, preclinical evaluation and
clinical trials.
5 Design attributes
5.1 General
The general requirements for non-active surgical implants outlined in ISO 14630 shall apply.
5.2 Concentration of the components
The concentration of each component material in the finished product shall be determined and documented,
and the concentration of each component shall be expressed as weight of material per unit volume of solution.
Since the testing methodology may affect the actual concentration reported, the standard physical or chemical
techniques utilized shall be described and documented. Wherever possible, components shall comply with
stated compendial standards.
5.3 Water used
The purity of the water used shall be Water for Injections (e.g. see [3]).
5.4 Characterization of the finished product
5.4.1 General
The manufacturer shall describe and document the physical characteristics that affect the performance of the
OIS efficacy in ophthalmic surgery.
NOTE These physical properties should be measured at the conditions expected and relevant at the time of use.
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
5.4.2 pH and buffering capacity
The pH of the finished product shall be determined and documented with a calibrated pH meter at
25 °C ± 2 °C.
NOTE The pH of the product should be close to that of the aqueous humour (pH 7,38) in order to prevent damage to
the corneal endothelial cells. In vitro studies have shown that the pH range tolerated by the endothelium narrows as
exposure time increases.
A suitable method shall be used to determine buffering capacity. An example of a suitable method is given in
Annex A. The products shall be classified as in Table 1.
Table 1 — Classification according to pH and buffering capacity
Base buffering capacity Acid buffering capacity
Group pH range
(mol/l per pH) (mol/l per pH)
Essentially unbuffered < 0,000 5 < 0,004 6,5 to 8,5
Moderately buffered 0,000 5 to 0,005 0,004 to 0,04 6,7 to 8,2
Buffered > 0,005 > 0,04 7,2 to 7,6
5.4.3 Chemical and biological contaminants
Potentially hazardous chemical or biological contaminants and impurities shall be determined by a risk
analysis. For raw materials of biological origin, these contaminants may include proteins, nucleic acids or
other biological materials. Contaminants of the finished product that are potentially hazardous either to the
tissues of the eye or systemically, shall be identified, whenever possible, and their concentrations in the
finished product reported.
Contaminants shall be determined using standard analytical methods when available, and all methods shall
be described. Limits for identified contaminants shall be set and included. Testing for the biological effects of
these contaminants during evaluation of biological safety may be required if the risk analysis determines it
necessary.
5.4.4 Osmolality
The manufacturer shall determine and document the osmolality range of the OIS. Osmolality of the finished
product shall be not less than 200 mosm/kg or greater than 400 mosm/kg. Osmolality shall be determined
using either a vapour pressure osmometer or a cryoscopic osmometer.
5.4.5 Spectral transmittance
The spectral transmittance of the finished product shall be recorded over the range 300 nm to 1 100 nm.
Results shall be presented graphically, plotting % transmission against wavelength.
5.4.6 Particulates
5.4.6.1 General
There is a potential for adverse events to take place as a result of particles of certain sizes and characteristics
in the finished product.
Particulate contamination of OISs consists of extraneous, mobile undissolved particles other than gas bubbles,
unintentionally present in the solutions.
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
A risk assessment shall evaluate the potential for contamination by, or formation of, particulates in the product
during manufacture as well as the conditions expected during transport and storage, and during use of the
product and the hazards associated with these.
In multi-component products (i.e. where there are two or more separate parts of a product that have to be
mixed prior to use) tests shall be applied to the mixed product.
5.4.6.2 Visible particles
The OIS shall be essentially free of visible particles. The method described in Annex B shall be used to
determine this.
5.4.6.3 Subvisible particles
Either the light obscuration test method given in Annex C or the microscopic test method given in Annex D
shall be used to determine the subvisible particulate level for OISs with the corresponding limits of each
method as given below.
The following limits shall apply for the light obscuration test method described in Annex C:
No more than 50 particles equal to or greater than 10 µm per ml of OIS;
No more than 5 particles equal to or greater than 25 µm per ml of OIS;
No more than 2 particles equal to or greater than 50 µm per ml of OIS.
The following limits shall apply for the microscopic test method of Annex D:
No more than 25 particles equal to or greater than 10 µm per ml of OIS;
No more than 2,5 particles equal to or greater than 25 µm per ml of OIS;
No more than 1 particle equal to or greater than 50 µm per ml of OIS.
NOTE The light obscuration test method of Annex C is based on light blockage. Amorphous, semiliquid or otherwise
morphologically indistinct materials contribute to light obscuration and therefore contribute to the particle count. In the
microscopic test method of Annex D, amorphous, semiliquid or otherwise morphologically indistinct materials appear as
stain or discolouration on the surface of the membrane filter, and are not counted as particles. To compensate for this
difference, the limits for the microscopic test method are one half those for the light obscuration method.
6 Design evaluation
6.1 General
The OIS shall be evaluated to demonstrate that the intended performance is achieved. The requirements for
evaluation of non-active implants outlined in ISO 14630 shall apply.
6.2 Preclinical evaluation of biological safety
6.2.1 General
The procedure for evaluation of biological safety of an OIS shall commence with an assessment of risk,
carried out and documented in accordance with ISO 14971-1. The results of the risk analysis shall determine
the tests required to evaluate the biological safety of the OIS.
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
For OISs containing material of animal origin the risk analysis and management requirements outlined in
EN 12442-1 shall apply.
NOTE 1 During the risk assessment the manufacturer should take into account the interaction with other ophthalmic
products.
For all OISs the requirements for evaluation of biological safety specified in ISO 10993-1 shall apply.
NOTE 2 Based upon the typical clinical applications, OISs are categorized as “Implant devices, tissue/bone”. The tests
for this and other categories of devices identified in Table 1 of ISO 10993-1:1997 are for guidance only. They do not
represent maximum or minimum test requirements.
NOTE 3 It may be possible to combine biocompatibility tests, thereby reducing the number of animals required for
testing. Multiple tests can be conducted simultaneously in a single animal provided that the test animal is not subjected to
undue pain or distress.
In addition to the biocompatibility tests identified in ISO 10993-1 and by the risk analysis, all of the following
tests shall be considered in the selection of tests to evaluate the biological safety of an OIS.
6.2.2 Bacterial endotoxins test
The OIS shall be evaluated for the presence of bacterial endotoxins using the Limulus Amebocyte Lysate
[5]
(LAL) test, in accordance with USP 24 or an equivalent, validated test procedure. Any product that exceeds
a bacterial endotoxin limit of 0,5 endotoxin units (EU) per ml fails the test.
6.2.3 Intraocular irritation and inflammation
If the risk assessment indicates that it is necessary to undertake tests for intraocular irritation, inflammation,
intraocular pressure and other local events, such tests shall be conducted in a suitable animal model in
accordance with Annex E. The choice of animal species shall be justified and documented. The animal
welfare requirements as described in ISO 10993-2 shall apply.
The animal testing shall mirror the intended clinical use as closely as possible.
The study design should assess the intraoperative and postoperative ocular irritation and inflammation of the
ophthalmic surgery, with comparative use of the OIS under evaluation and a control OIS that has already
been proven to be non-irritating and non-inflammatory in clinical use for five years. The volume of OIS used
shall simulate the intended use, accounting for ocular volume differences between the human eye and that of
the animal model.
The post-surgical irritation and inflammation shall be monitored and graded in accordance with Annex E.
Based upon the risk management plan, appropriate evaluation at appropriate times may include corneal
pachymetry and slit lamp biomicroscopy. All adverse effects shall be documented.
The OIS shall show ocular irritation and inflammation results less than or equal to the control OIS, or it shall
be excluded from clinical use.
6.3 Clinical evaluation
If clinical evaluation and risk assessment identify the need for a clinical investigation, Annex F shall be
considered. In addition, the general requirements concerning clinical investigations of medical devices for
human subjects specified in ISO 14155-1 and ISO 14155-2 shall apply.
7 Sterilization
Whenever possible, the product shall be terminally sterilized in its final container. The requirements for
sterilization of non-active surgical implants outlined in ISO 14630 shall apply.
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
Ethylene oxide shall not be used to sterilize the OIS solution and, unless justified, not to sterilize the primary
container either. In case of justification and use for the latter, ethylene oxide and related contaminants may
diffuse into the solution, for which the following limits shall then apply:
ethylene oxide: less than 20 µg/ml
ethylene chlorohydrin: less than 100 µg/ml
NOTE 1 It has been found that the requirements determining acceptable limits for ethylene oxide residuals specified in
ISO 10993-7 are inadequate for devices in contact with highly sensitive tissues, such as those of the eye. For this case
AAMI TIR No. 19 provides additional guidance to the application of ISO 10993-7.
For OISs that are not terminally sterilized, but aseptically processed, ISO 13408-1 shall apply. The process
−3
shall be demonstrated to comply with a contamination rate limit of 10 by a validated media fill study.
NOTE 2 ISO 13408-1 specifies the general requirements for, and offers guidance on, processes, programmes and
procedures for the validation and control of aseptically processed health care products. ISO 13408-1 particularly applies,
but is not limited to, the processing of aqueous solutions, and is thus relevant to the preparation of OISs. Future parts of
that International Standard will address specialized processes, such as filtration and lyophilization.
8 Product stability
The manufacturer shall define and state the shelf life of the product. Real time or accelerated shelf life testing
shall be performed to demonstrate that the finished product remains within specifications for a period of the
labelled shelf life under expected conditions of transport and storage. Real time testing shall reflect normal
storage temperature and temperature fluctuations and the relative humidity shall be controlled within
60 % ± 20 %. In accelerated testing the temperature shall not exceed 45 °C and the relative humidity shall be
at least 40 %. The parameters that shall be followed during shelf life studies are the pH, osmolality, particulate
[5-8]
levels, sterility (using EP, JP or USP ), colour and clarity, plus any other factors identified by risk analysis
as crucial to safe use of the product.
The established shelf life of the OIS shall be re-validated if a risk assessment identifies any change in
manufacture that may affect the stability of the product.
NOTE Changes in the composition of the product, source materials, material suppliers, manufacturing conditions,
including the sterilization process, package design or package materials may affect the shelf life of the product.
9 Packaging
9.1 Protection from damage during storage and transport
The packaging requirements for medical devices outlined in ISO 11607 and ISO 14630 shall apply.
9.2 Maintenance of sterility in transit
OISs shall be packaged in such a way that they remain sterile or below the contamination rate specified, as
applicable, within the limits specified for conditions of transport, storage and handling. The sterile packaging
requirements outlined in EN 868-1 shall apply.
10 Information supplied by the manufacturer
The general requirements for information provided by the manufacturer of medical devices specified in
EN 1041 shall apply together with the following particular requirements. Symbols may be used instead of text,
where appropriate. When symbols are used the requirements of ISO 15223 shall apply.
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SIST EN ISO 16671:2004
ISO 16671:2003(E)
The labelling shall contain information on whether the OIS is buffered and if so give information on the buffer
type and capacity.
If the product is vulnerable to damage by exposure to environmental elements, there shall be clear warning
signs on the shipping container.
NOTE The batch number and expiration date may be provided on a self-adhesive label.
A package insert shall be included within the storage container, provided in such a way that it can be removed
and read without damaging the sterile barrier.
The minimum information required on the storage container, package insert, sterile barrier and primary
container is listed in Table 2.
Table 2 — Information supplied by the manufacturer
Sterile
Storage Package Primary
Information barrier (if
container insert container
present)
Name of the manufacturer or authorized representative × × × ×
Address of the manufacturer or authorized representative × ×
Trade name of product × × × ×
Brief description of the chemical composition of the product
× ×
and the volume supplied
Conditions for storage
...
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