1、April 2013 Translation by DIN-Sprachendienst.English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 1
2、1.040.70!$N“1999343www.din.deDDIN EN ISO 22665Ophthalmic optics and instruments Instruments to measure axial distances in the eye (ISO 22665:2012);English version EN ISO 22665:2012,English translation of DIN EN ISO 22665:2013-04Augenoptik und ophthalmische Instrumente Instrumente zur Messung der Ach
3、slnge des Auges (ISO 22665:2012);Englische Fassung EN ISO 22665:2012,Englische bersetzung von DIN EN ISO 22665:2013-04Optique et instruments ophtalmiques Appareil pour le mesurage de la longueur axiale de loeil (ISO 22665:2012);Version anglaise EN ISO 22665:2012,Traduction anglaise de DIN EN ISO 226
4、65:2013-04www.beuth.deDocument comprises pagesIn case of doubt, the German-language original shall be considered authoritative.1303.13DIN EN ISO 22665:2013-04 2 A comma is used as the decimal marker. National foreword This document (EN ISO 22665:2012) has been prepared by Technical Committee ISO/TC
5、172 “Optics and photonics” in collaboration with Technical Committee CEN/TC 170 “Ophthalmic optics” (both secretariats are held by DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Feinmechanik und Optik (Optics and Precision Mechanics Standards Committee
6、), Working Committee NA 027-01-20 AA Intraokulare Medizinprodukte. The DIN Standard corresponding to the International Standard referred to in Clause 2 of this standard is as follows: IEC 60601-1 DIN IEC 60601-1/A1 (VDE 0750/A1) National Annex NA (informative) Bibliography DIN IEC 60601-1/A1 (VDE 07
7、50-1/A1), Medical electrical equipment Part 1: General requirements for basic safety and essential performance EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 22665 December 2012 ICS 11.040.70 English Version Ophthalmic optics and instruments - Instruments to measure axial distances in the
8、eye (ISO 22665:2012) Optique et instruments ophtalmiques - Appareil pour le mesurage de la longueur axiale de loeil (ISO 22665:2012)Augenoptik und ophthalmische Instrumente - Instrumente zur Messung der Achslnge des Auges (ISO 22665:2012)This European Standard was approved by CEN on 30 November 2012
9、. 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
10、 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-CENEL
11、EC 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy
12、, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17,
13、 B-1000 Brussels 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 22665:2012: EContents Page DIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 2 Foreword 3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definit
14、ions .5 4 Requirements .6 5 Test methods 6 5.1 General 6 5.2 True parameters of the test bodies 6 5.3 Measurements with ultrasound biometry instruments 7 5.4 Measurements with optical biometry instruments .7 6 Accompanying documents .7 7 Marking .7 Annex A (normative) Test bodies and evaluation of m
15、easurements .8 A.1 Test bodies .8 A.1.1 General 8 A.1.2 Material properties .8 A.1.3 Geometry of test cylinders .9 A.2 Evaluation of measurements 10 A.2.1 Measurements using ultrasound biometry instruments .10 A.2.2 Measurements using optical biometry instruments 10 Bibliography 11 Foreword This doc
16、ument (EN ISO 22665:2012) 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 pub
17、lication of an identical text or by endorsement, at the latest by June 2013, and conflicting national standards shall be withdrawn at the latest by June 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shal
18、l not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denm
19、ark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement no
20、tice The text of ISO 22665:2012 has been approved by CEN as a EN ISO 22665:2012 without any modification. “DIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 3 IntroductionThe measurement of the axial length of the human eye is one of the pre-requisites for the calculation of the necessary power of an a
21、rtificial lens that is to be implanted in the eye during cataract and/or refractive surgery.Since the 1950s ultrasound biometry instruments have been used for ocular distance measurements. Depending on how the sound waves are coupled into the eye, two different measurement methods are applied in ult
22、rasound biometry: immersion and contact techniques. In recent years, optical biometry instruments based on partial coherence interferometry have established themselves as an alternative to echometry.Neither instrument is calibrated against a common standard. As a result, there are systematic differe
23、nces between measurements taken with different biometers. The resulting errors can affect surgical outcomes for patients.DIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 4 1 ScopeThis International Standard is applicable to instruments and methods used for measuring the axial length of the human eye.I
24、t defines minimum requirements for such instruments and systems and defines test methods and procedures to verify that a system or instrument qualifies as an axial length measuring device in accordance with this International Standard.2 Normative referencesThe following referenced documents are indi
25、spensable 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.IEC 60601-1, Medical electrical equipment Part 1: General requirements for basic safety and e
26、ssential performance3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1axial lengthdistance along the axis of a human eye between the anterior corneal surface to either the inner limiting membrane (ILM) of the retina or the retinal pigment epitheli
27、um (RPE) of the retinaNOTE The separation between the ILM (anterior retina) and RPE (posterior retina) is approximately 100 m at the centre of the fovea and 300 m immediately outside the fovea. Different methods exist to assess axial length, e.g. peak and rising edge detection of fundus echoes in ul
28、trasound instruments (using ILM) or determination of the optical path length to the RPE in optical biometry.3.2aphakic modemeasurement mode and/or instrument setting for an axial length measuring device which is to be used for the measurement of an aphakic eye (eye without lens)3.3contact ultrasound
29、contact modecoupling technique in echo biometry by which the measuring transducer probe is in direct contact with the cornea3.4echo biometrymethod to determine the axial length of a human eye by measuring the time of flight of an ultrasound pulse between two echo-generating structures in the eye3.5g
30、roup refractive indexratio c0/cgbetween the speed of light in vacuum (c0) and the group velocity of light propagation (cg) through a medium or a biological tissueDIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 5 3.6immersion ultrasoundimmersion modecoupling technique in echo biometry by which the mea
31、suring transducer probe is separated from the cornea by a water or liquid standoff3.7optical biometryoptical method to measure the axial length of a human eye3.8phakic modemeasurement mode and/or instrument setting for an axial length measuring device which is to be used for the measurement of a pha
32、kic eye (eye with a crystalline lens)3.9acoustical impedanceZ material property defined as the product of the velocity of sound in that material with its density:Z =where is the velocity of sound in the material; is the density of the material.4 RequirementsThe axial length measuring device shall co
33、nform to the requirements given below. Conformity shall be verified as described in Clause 5.The radial and axial dimensions of three test bodies conforming to the requirements of Annex A shall be determined using the instrument under test and shall be compared to the true dimensions. All measured v
34、alues shall lie within 100 m of the true dimensions.5 Test methods5.1 GeneralThe measurements aim at comparing axial and radial dimensions of the test cylinders.All test bodies shall be placed in a position relative to the measuring instrument or sensor (transducer) which is comparable to the patien
35、ts eye position during clinical measurements. Axial measurements are to be performed along the cylinder axis, radial measurements along a diameter. In each orientation, 10 independent measurements shall be carried out and averaged to give the respective test cylinder dimension.To perform independent
36、 measurements it is necessary to adjust the measuring device anew for each new single measurement.5.2 True parameters of the test bodiesThe true dimensions of the test bodies shall be determined using a mechanical calliper with an accuracy of at least or better than 10 m, preferably at the same temp
37、erature at which the measurements with the axial length measuring devices were performed. Test results shall be evaluated according to the general rules of statistics.The group refractive index and the velocity of sound and their temperature dependences, as well as the acoustical impedance of the ma
38、terial, are to be specified.DIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 6 5.3 Measurements with ultrasound biometry instrumentsMeasurements using ultrasound instruments shall be performed in contact mode as well as in immersion mode. For immersion measurements, the test cylinders are to be immers
39、ed in distilled water in a suitable cuvette and oriented according to the desired dimension to be measured.To prevent excessive uptake of water, the test bodies shall only be immersed in water for the duration of the measurements.The ultrasound instrument has to be set up to operate in the aphakic m
40、ode.The temperature of the test bodies shall be determined in order to allow a temperature correction for the propagation speed of sound through the test body material.The measured values are transformed into times of flight and then reconverted into geometrical distances by means of the temperature
41、-corrected velocity of sound for the test body material. For details, see Annex A.5.4 Measurements with optical biometry instrumentsThe optical biometry instrument has to be set up to operate in a mode which allows the optical path length of the test body to be obtained.The temperature of the test b
42、odies shall be determined in order to allow a temperature correction for the group refractive index of the test body material.The measured values are then reconverted into geometrical distances by means of the temperature-corrected group refractive index for the test body material. For details, see
43、Annex A.6 Accompanying documentsThe instrument shall be accompanied by documents containing instructions for use and any necessary precautions. In particular, these documents shall contain the following information:a) name and address of the manufacturer or his authorized representative as required
44、by legislation;b) instructions as to effective disinfection of the components of the axial length measuring device which are in contact with the patient with particular reference to instruments returned to the manufacturer for repair and maintenance;c) any additional documents as specified in IEC 60
45、601-1;d) a reference to this International Standard, i.e. ISO 22665:2012, if the manufacturer or supplier claims compliance with it;e) instructions for use, if not already specified by IEC 60601-1.7 MarkingThe instrument shall be permanently marked with at least the following information:a) name and
46、 address of manufacturer or supplier;b) name, model, serial number;c) additional marking as required by IEC 60601-1.DIN EN ISO 22665:2013-04 EN ISO 22665:2012 (E) 7 Annex A (normative) Test bodies and evaluation of measurementsA.1 Test bodiesA.1.1 GeneralThe test bodies are cylinders made of a suita
47、ble material that represent the distances of small, medium and long eyes; they shall be manufactured with a tolerance 0,01 mm.PMMA has been used in a variety of ultrasound applications as an echo-generating material; millions of PMMA lenses have been implanted in human eyes, the axial length of whic
48、h is measured by ultrasound. Therefore, A.1.2 gives the specification of a test body on the basis of the relevant material parameters for test bodies made from PMMA.Other suitable materials may be used and will be necessary, e. g. for ultrasound biometry instruments that may not be sensitive enough
49、to display echoes with a long travel time through PMMA.When selecting an appropriate material, it is recommended to consider the materials acoustical impedance to cause changes similar to those at the tissue margins to be detected in the human eye.NOTE 1 Otherwise, the detection mechanism will be different from that of the human eye, thereby causing a non-negligible impact on the measured axial lengths.NOTE 2 Consideration may be given to selecting a combination of more than one material.If a material other than PMMA is to be used, the specification of
