SIST EN ISO 11979-5:2020

Ophthalmic implants - Intraocular lenses - Part 5: Biocompatibility (ISO 11979-5:2020)

This document specifies particular requirements for the biocompatibility evaluation of materials for
intraocular lenses (IOLs) including the processing conditions to produce them. These requirements
include evaluation of physicochemical properties that are relevant to biocompatibility. It also gives
guidance on conducting an ocular implantation test.

Ophthalmische Implantate - Intraokularlinsen - Teil 5: Biokompatibilität (ISO 11979-5:2020)

Dieses Dokument legt die besonderen Anforderungen an die Bewertung der Biokompatibilität von Materialien für Intraokularlinsen (IOLs) sowie der bei deren Herstellung angewendeten Verfahren bzw. Bedingungen fest. Diese Anforderungen beinhalten die Bewertung der physikalisch-chemischen Eigen-schaften, die für die Biokompatibilität von Belang sind. Zudem gibt es eine Anleitung zur Durchführung einer Untersuchung zur intraokularen Implantation.

Implants ophtalmiques - Lentilles intraoculaires - Partie 5: Biocompatibilité (ISO 11979-5:2020)

Le présent document spécifie des exigences particulières relatives à l'évaluation de la biocompatibilité des matériaux des lentilles intraoculaires (LIO), y compris les conditions de traitement liées à leur fabrication. Ces exigences comprennent l'évaluation des propriétés physicochimiques relatives à la biocompatibilité. Le présent document donne également des recommandations relatives à la réalisation d'un essai d'implantation oculaire.

Očesni vsadki (implantati) - Intraokularne leče - 5. del: Biokompatibilnost (ISO 11979-5:2020)

General Information

• Status: Published
• Public Enquiry End Date: 04-Sep-2019
• Publication Date: 11-Nov-2020
• ICS: 11.040.70 - Ophthalmic equipment
• Technical Committee: VAZ - Healthcare
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 19-Oct-2020
• Due Date: 24-Dec-2020
• Completion Date: 12-Nov-2020
• Ref Project: EN ISO 11979-5:2020 - Ophthalmic implants - Intraocular lenses - Part 5: Biocompatibility (ISO 11979-5:2020)

Relations

• Replaces: SIST EN ISO 11979-5:2006 - Ophthalmic implants - Intraocular lenses - Part 5: Biocompatibility (ISO 11979-5:2006)
• Effective Date: 01-Dec-2020
• Replaces: SIST EN ISO 11979-5:2006 - Ophthalmic implants - Intraocular lenses - Part 5: Biocompatibility (ISO 11979-5:2006)
• Effective Date: 08-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 11979-5:2020
01-december-2020
Nadomešča:
SIST EN ISO 11979-5:2006
Očesni vsadki (implantati) - Intraokularne leče - 5. del: Biokompatibilnost (ISO
11979-5:2020)

Ophthalmic implants - Intraocular lenses - Part 5: Biocompatibility (ISO 11979-5:2020)

Ophthalmische Implantate - Intraokularlinsen - Teil 5: Biokompatibilität (ISO 11979-

5:2020)

Implants ophtalmiques - Lentilles intraoculaires - Partie 5: Biocompatibilité (ISO 11979-

5:2020)
Ta slovenski standard je istoveten z: EN ISO 11979-5:2020
ICS:
11.040.70 Oftalmološka oprema Ophthalmic equipment
SIST EN ISO 11979-5:2020 en

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN ISO 11979-5:2020
---------------------- Page: 2 ----------------------
SIST EN ISO 11979-5:2020
EN ISO 11979-5
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2020
EUROPÄISCHE NORM
ICS 11.040.70 Supersedes EN ISO 11979-5:2006
English Version
Ophthalmic implants - Intraocular lenses - Part 5:
Biocompatibility (ISO 11979-5:2020)

Implants ophtalmiques - Lentilles intraoculaires - Ophthalmische Implantate - Intraokularlinsen - Teil 5:

Partie 5: Biocompatibilité (ISO 11979-5:2020) Biokompatibilität (ISO 11979-5:2020)

This European Standard was approved by CEN on 22 September 2020.

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 CEN-CENELEC 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 CEN-CENELEC Management

Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11979-5:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 11979-5:2020
EN ISO 11979-5:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

---------------------- Page: 4 ----------------------
SIST EN ISO 11979-5:2020
EN ISO 11979-5:2020 (E)
European foreword

This document (EN ISO 11979-5:2020) has been prepared by Technical Committee ISO/TC 172 "Optics

and photonics" in collaboration with 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 April 2021, and conflicting national standards shall be

withdrawn at the latest by April 2021.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 11979-5:2006.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,

Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,

Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of

North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the

United Kingdom.
Endorsement notice

The text of ISO 11979-5:2020 has been approved by CEN as EN ISO 11979-5:2020 without any

modification.
---------------------- Page: 5 ----------------------
SIST EN ISO 11979-5:2020
---------------------- Page: 6 ----------------------
SIST EN ISO 11979-5:2020
INTERNATIONAL ISO
STANDARD 11979-5
Third edition
2020-09
Ophthalmic implants — Intraocular
lenses —
Part 5:
Biocompatibility
Implants ophtalmiques — Lentilles intraoculaires —
Partie 5: Biocompatibilité
Reference number
ISO 11979-5:2020(E)
ISO 2020
---------------------- Page: 7 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ................................................................................................................................................................................................................................vi

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 General requirements applying to biocompatibility evaluation of intraocular lenses ..............2

5 Physicochemical tests...................................................................................................................................................................................... 3

5.1 General ........................................................................................................................................................................................................... 3

5.2 Physical/Chemical description ................................................................................................................................................. 4

5.3 Exhaustive extraction test ............................................................................................................................................................. 4

5.4 Test for leachables ................................................................................................................................................................................ 4

5.5 Test for hydrolytic stability .......................................................................................................................................................... 4

5.6 Photostability test ................................................................................................................................................................................ 5

5.7 Nd-YAG laser exposure test ........................................................................................................................................................... 6

5.8 Evaluation of insoluble inorganics ......................................................................................................................................... 6

6 Biological tests ........................................................................................................................................................................................................ 7

6.1 General ........................................................................................................................................................................................................... 7

6.2 Test for cytotoxicity............................................................................................................................................................................. 7

6.3 Tests for sensitization ....................................................................................................................................................................... 7

6.4 Tests for genotoxicity ........................................................................................................................................................................ 7

6.5 Test for local effects ............................................................................................................................................................................ 8

6.6 Ocular implantation test ................................................................................................................................................................. 8

Annex A (normative) Exhaustive extraction test ..................................................................................................................................... 9

Annex B (normative) Test for leachables ......................................................................................................................................................13

Annex C (normative) Hydrolytic stability .....................................................................................................................................................15

Annex D (normative) Photostability test ......................................................................................................................................................18

Annex E (normative) Nd-YAG laser exposure test ................................................................................................................................20

Annex F (normative) Supplemental conditions of test for local effects after implantation ....................22

Annex G (normative) Ocular implantation test ......................................................................................................................................23

Bibliography .............................................................................................................................................................................................................................27

© ISO 2020 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).

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. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/ patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see

www .iso .org/ iso/ foreword .html.

This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee

SC 7, Ophthalmic optics and instruments, in collaboration with the European Committee for

Standardization (CEN) Technical Committee CEN/TC 170, Ophthalmic optics, in accordance with the

Agreement on technical cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 11979-5:2006), which has been

technically revised.
The main changes compared to the previous edition are as follows:
— correction and addition of references throughout the document;
— added more specific guidance on risk-based approach throughout the document;
— added requirement to use state of the art analytical methods;
— update of apparatus lists where applicable;

— clarification of test material in Tables 1 and 2, reference to ISO/TR 22979 when the IOL is a

modification of a parent IOL and requirement for a biological evaluation plan added to Clause 4;

— combination and re-writing of physicochemical test methods and their objectives in Table 3 of 5.1;

— added requirement for physical/chemical description and contaminants in 5.2;

— revised order of tests in 6.1 for alignment with ISO 10993 and added subclauses for every test;

— clarification of ratio for material and extraction medium in biological tests in 6.1;

— principle and procedure of exhaustive extraction is explained in more detail (Annex A);

— in hydrolytic stability, products are their own control for spectral transmittance and dioptric power

(Annex C);
iv © ISO 2020 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)

— removed the allowance of representative test material for photostability testing, added the

requirement to measure lens power and image quality (Annex D);
— Annex F change from informative to normative;

— duration of subcutaneously or intramuscularly implantation increased from 4 weeks to 3 months

(Annex F);

— duration of ocular implantation test in rabbits reduced from 6 months to 3 months (Annex G).

A list of all parts in the ISO 11979 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/ members .html.
© ISO 2020 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
Introduction

This document follows the general principles given in ISO 10993-1. ISO 10993-1 describes the principles

governing the biological evaluation of medical devices, the definitions of categories based on the nature

and duration of contact with the body, and selection of appropriate tests. Other parts of ISO 10993

present biological test methods, tests for ethylene oxide residues, tests for degradation and principles

for sample preparation.
vi © ISO 2020 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 11979-5:2020
INTERNATIONAL STANDARD ISO 11979-5:2020(E)
Ophthalmic implants — Intraocular lenses —
Part 5:
Biocompatibility
1 Scope

This document specifies particular requirements for the biocompatibility evaluation of materials for

intraocular lenses (IOLs) including the processing conditions to produce them. These requirements

include evaluation of physicochemical properties that are relevant to biocompatibility. It also gives

guidance on conducting an ocular implantation test.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements 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.

ISO 10993-1, Biological evaluation of medical devices — Part 1: Evaluation and testing within a risk

management process

ISO 10993-2, Biological evaluation of medical devices — Part 2: Animal welfare requirements

ISO 10993-3, Biological evaluation of medical devices — Part 3: Tests for genotoxicity, carcinogenicity and

reproductive toxicity

ISO 10993-5, Biological evaluation of medical devices — Part 5: Tests for in vitro cytotoxicity

ISO 10993-6, Biological evaluation of medical devices — Part 6: Tests for local effects after implantation

ISO 10993-10, Biological evaluation of medical devices — Part 10: Tests for irritation and skin sensitization

ISO 10993-12, Biological evaluation of medical devices — Part 12: Sample preparation and reference

materials

ISO 10993-17, Biological evaluation of medical devices — Part 17: Establishment of allowable limits for

leachable substances
ISO 11979-1, Ophthalmic implants — Intraocular lenses — Part 1: Vocabulary

ISO 11979-2, Ophthalmic implants — Intraocular lenses — Part 2: Optical properties and test methods

ISO 11979-3, Ophthalmic implants — Intraocular lenses — Part 3: Mechanical properties and test methods

ISO 14971, Medical devices — Application of risk management to medical devices

ISO 18369-4, Ophthalmic optics — Contact lenses — Part 4: Physicochemical properties of contact lens

materials

ISO/TS 21726, Biological evaluation of medical devices — Application of the threshold of toxicological

concern (TTC) for assessing biocompatibility of medical device constituents

ISO/TR 22979, Ophthalmic implants — Intraocular lenses — Guidance on assessment of the need for clinical

investigation of intraocular lens design modifications
© ISO 2020 – All rights reserved 1
---------------------- Page: 13 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 11979-1 apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 General requirements applying to biocompatibility evaluation of
intraocular lenses

The evaluation of the biocompatibility of the test material shall start with an initial assessment of risk

in accordance with ISO 14971. Refer to Table 1, Table 2 and ISO 11979-1 for definition of test material

and allowance of representative samples. At a minimum, independent from the initial risk assessment

outcome, the tests described in Clause 5 shall be performed to characterize the physicochemical

properties of the intraocular lens. The evaluation of the material for biological safety shall then be

undertaken per biological evaluation plan, in accordance with the principles and requirements of

ISO 10993-1 and ISO 10993-2, taking into consideration the results from the physicochemical tests.

Furthermore, the risk assessment shall include an assessment of the potential for material changes

such as calcification. This risk assessment should consider the history of clinical use of the material,

and animal models to test the long-term stability of the material.

Carry out the biocompatibility testing in accordance with ISO 10993-1, ISO 10993-2, ISO 10993-3,

ISO 10993-5, ISO 10993-6, ISO 10993-10, ISO 10993-12, ISO 10993-17 and ISO/TS 21726 and as noted in

this document.

The pre-existing information on the material and all the information obtained in the evaluation process

shall be integrated in an overall risk benefit assessment in accordance with ISO 14971. ISO 10993-1

describes the content of such evaluation.
Refer to ISO/TR 22979 when the IOL is a modification of a parent IOL.
Table 1 — Allowance of representative samples for physicochemical tests
Test material
Test
Sterile finished Representative
IOL sample
Exhaustive extraction X X
Leachables X X
Hydrolytic stability X X
Photostability against UV/Vis irradiation X
Stability against Nd-YAG laser exposure X
Insoluble inorganics X

Sample, manufactured and processed, including intended sterilization, using a procedure

equivalent to that used for the intraocular lens, that has the same central thickness as the final

product (typically 20,0 D IOL).
2 © ISO 2020 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
Table 2 — Allowance of representative samples for biological tests
Test material
Test
Sterile finished Representative
IOL sample
Cytotoxicity X X
Sensitization X X
Genotoxicity X X
Local effects after implantation X X
Ocular implantation test X

Sample, manufactured and processed, including intended sterilization, using a procedure

equivalent to that used for the intraocular lens, that has the same central thickness as the final

product (typically 20,0 D IOL).

To allow for dimensional differences between human and animal eyes, the IOL could require

scaling to fit the anatomical placement site of the animal.
5 Physicochemical tests
5.1 General

The physicochemical tests listed in Table 3 shall be performed to characterize the physicochemical

properties of the IOL and to facilitate an analysis of any risk introduced by chemical compounds which

may result from processing, treatment in use, or (simulated) ageing of the test material. The results of

the tests in Table 3 should be used as input for the risk assessment in accordance with ISO 14971.

The outcomes of the physicochemical tests should be subjected to systemic toxicologically evaluation

according to ISO 10993-17 and ISO/TS 21726.
Table 3 — Physicochemical tests and their objectives
Test Objectives

a) Exhaustive extraction To identify and quantify the total amount of extractable material that is

present in the IOL, possible residues from synthesis and additives or
impurities from manufacturing and packaging and to be used for
performing the risk assessment.
b) Leachables To identify and quantify the substances that are released from IOL
under simulated physiological conditions and to be used for determining
the risk during the clinical use.

c) Hydrolytic stability To identify and quantify possible degradation products due to

hydrolysis to determine the stability of an IOL in an aqueous
environment and to assess the risk for potentially harmful effects
due to hydrolytic degradation products.

d) Photostability against To characterize the effect of UV/Vis irradiation on the optical,

ultraviolet/visible (UV/Vis) mechanical and chemical properties of the IOL and to assess the

irradiation risk for potentially harmful effects of degradation products due to
irradiation.

e) Stability against Nd-YAG To identify the effect of Nd-YAG laser treatment on the chemical

laser exposure properties of the IOL and to assess the risk for potentially harmful

effects of degradation products due to Nd-YAG laser exposure.

f) Insoluble inorganics To quantify the levels of insoluble inorganics which may result from

manufacturing processing and packaging and to assess the risk from
insoluble inorganics.
© ISO 2020 – All rights reserved 3
---------------------- Page: 15 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
5.2 Physical/Chemical description

The manufacturer shall provide a description of each of the components in the formulation to facilitate

the interpretation of physical and chemical test results.
For description of each component the manufacturer shall provide, if available:

a) Name — Provide the chemical name and Chemical Abstracts Service (CAS) registry number;

b) Structure formula — Provide the chemical structure and molecular formula;

c) If the component material is derived from biological sources, the organism from which it is obtained

shall be stated along with its source.
For the finished polymer the manufacturer shall provide, if available:
d) Structure formula — Provide the chemical structure and molecular formula.
5.3 Exhaustive extraction test

The test material shall be tested for extractables under exhaustive extraction conditions in accordance

with the method specified in Annex A. Alternative methods can be used, provided that they have been

validated and are reflective of the current state of the art.
The following shall be observed:
a) The reasons for selecting each solvent shall be justified and documented.

b) The test material shall be weighed before and after extraction and any change in mass shall be

calculated.

c) The extraction media shall be qualitatively and quantitatively analysed at the end of extraction

for possible extractable components of the material, such as process contaminants, residual

monomers, additives, and other extractable components.

The results shall be evaluated to assess the risk for potentially harmful effects due to extractable

components.
5.4 Test for leachables

The test material shall be tested for leachables under simulated physiological conditions in accordance

with the method specified in Annex B. Alternative analytical methods can be used that are reflective of

the current state of the art in common use.
The following shall be observed:
a) The reasons for selecting each solvent shall be justified and documented.

b) The extraction media shall be qualitatively and quantitatively analysed at the end of extraction for

possible leachables of the material, such as process contaminants, residual monomers, additives,

and other leachables.

The results shall be evaluated to assess the risk for potentially harmful effects due to leachable

components.
5.5 Test for hydrolytic stability

Hydrolytic stability testing shall be conducted in accordance with the method specified in Annex C.

4 © ISO 2020 – All rights reserved
---------------------- Page: 16 ----------------------
SIST EN ISO 11979-5:2020
ISO 11979-5:2020(E)
The following shall be observed:

a) The study shall be designed to evaluate the stability of the material in an aqueous environment at

35 °C ± 2 °C for a period of at least five years or at an elevated temperature for a simulated exposure

time of at least five years.

NOTE Five years is considered sufficiently long to show changes when the product is not hydrolytically

stable and is considered appropriate since only limited test acceleration is possible.

b) The simulated exposure time is to be determined by multiplying the actual study time with the

following acceleration factor F:
(Ta-To)/10
F = 2,0
where
T is the accelerated temperature;
T is the temperature of the inside of the eye (35 °C).

c) The exposure medium shall be qualitatively and quantitatively analysed for any chemical entities

at the end of the exposure period.

d) The test material shall be examined by light microscopy at ×10 or higher and by scanning electron

microscopy (SEM) at ×500 or higher before and after testing. The test material shall be compared

with the untreated material and there shall be no significant difference in surface appearance

(e.g. bubbles, dendrites, breaks and fissures).

e) Optical transmittance spectra of the test material in the ultraviolet and visible spectral regions

(UV/Vis) shall be recorded before and after testing. By comparison of the spectra, assurance shall

be obtained that there are no significant changes in spectral transmittance.

f) The dioptric power shall be determined before and after testing if finished IOLs are used in the

testing. The refractive index shall be determined instead if a facsimile material is used. There

shall be no average absolute change in dioptric power greater than 0,25 D for a 20 D lens or a

corresponding change in refractive index comparing before testing and after exposure to the

simulated time of at least 5 years.

The results shall be evaluated to assess the risk for potentially harmful effects due to instability of the

material in an aqueous environment.
5.6 Photostability test
Photostability testing shall be conducted in accordance with Annex D.
The following shall be observed:

a) There shall be no changes in appearance of the irradiated test material when compared with non-

irradi
...