EN IEC 62985:2019
(Main)Methods for calculating size specific dose estimates (SSDE) on computed tomography
Methods for calculating size specific dose estimates (SSDE) on computed tomography
IEC 62985:2019 applies to – CT SCANNERS that are able to display and report CTDIVOL in accordance with IEC 60601-2-44, and – RADIATION dose index monitoring software (RDIMS) for the purpose of calculating, displaying and recording the SIZE SPECIFIC DOSE ESTIMATE (SSDE) and its associated components. Specifically, this document provides standardized methods and requirements for calculating, displaying, or recording of SSDE, SSDE(z), WATER EQUIVALENT DIAMETER (DW), and DW(z), where z represents a specific longitudinal position of the scanned object. This document provides a method of determining a reference WATER EQUIVALENT DIAMETER, DW,REF(z), using CT scans of two cylindrical water PHANTOMS and one or more anthropomorphic PHANTOM(S), which conform to the specifications defined in this document. The method of calculating the WATER EQUIVALENT DIAMETER that is implemented by the MANUFACTURER, DW,IMP(z), is tested and validated against DW,REF(z) using the TEST OBJECTS and methods defined within this document. This document also describes the methods for calculating SSDE and DW, which represent the average values of SSDE(z) and DW(z) over the RECONSTRUCTION LENGTH.
Verfahren für die Berechnung größenspezifischer Dosisschätzungen (SSDE) für die Computertomographie
Méthodes de calcul de l’estimateur de dose morphologique (SSDE) en tomodensitométrie
L'IEC 62985:2019 s’applique: – aux TOMODENSITOMETRES qui sont capables d’afficher et de notifier CTDIVOL conformément à l’IEC 60601-2-44, et – au logiciel de surveillance de l’indice de dose de RAYONNEMENT (RDIMS - RADIATION Dose Index Monitoring Software) pour les besoins de calcul, d’affichage et d’enregistrement de l’ESTIMATEUR DE DOSE MORPHOLOGIQUE (SSDE) et de ses composantes associées. Plus spécifiquement, le présent document fournit des méthodes et des exigences normalisées pour le calcul, l’affichage ou l’enregistrement du SSDE, du SSDE(z), du DIAMETRE EQUIVALENT EAU (DW), et de DW(z), où z représente une position longitudinale spécifique de l’objet balayé. Le présent document fournit une méthode permettant de déterminer un DIAMETRE EQUIVALENT EAU de référence, DW,REF(z), par balayage TOMOGRAPHIQUE de deux FANTOMES d’eau cylindriques et d’un ou plusieurs FANTOMES anthropomorphiques conformes aux spécifications définies dans le présent document. La méthode de calcul du DIAMETRE EQUIVALENT EAU appliquée par le FABRICANT, DW,IMP(z), est vérifiée par essai et validée par rapport à la valeur DW,REF(z) en utilisant les OBJETS D’ESSAI et les méthodes définis dans le présent document. Le présent document décrit également les méthodes de calcul du SSDE et DW, qui représentent les valeurs moyennes du SSDE(z) et du DW(z) sur l’ensemble de la LONGUEUR DE RECONSTRUCTION.
Metode za izračun doze obsevanja glede na velikost obsevanca (SSDE) pri računalniški tomografiji (IEC 62985:2019)
Ta dokument se uporablja za: – NAPRAVE CT, ki lahko prikazujejo in poročajo CTDIVOL v skladu s standardom IEC 60601-2-44; in – programsko opremo za spremljanje indeksa odmerka OBSEVANJA (RDIMS) za namene izračunavanja, prikazovanja ter beleženja DOZE OBSEVANJA GLEDE NA VELIKOST OBSEVANCA (SSDE) in njenih povezanih komponent. Natančneje, ta dokument podaja standardizirane metode in zahteve za izračunavanje, prikazovanje ali beleženje SSDE, SSDE(z), VODNEGA EKVIVALENTNEGA PREMERA (DW) in DW(z), pri čemer z označuje določen vzdolžni položaj slikanega objekta. Ta dokument določa metodo za določevanje referenčnega VODNEGA EKVIVALENTNEGA PREMERA, DR,REF(z), s slikanji CT dveh valjastih vodnih FANTOMOV in enega ali več antropomorfnih FANTOMOV, ki so skladni s specifikacijami, določenimi v tem dokumentu. Metoda za izračun VODNEGA EKVIVALENTNEGA PREMERA, ki jo uporablja PROIZVAJALEC, DW,IMP(z), se preskuša in potrdi glede na DW,REF(z) z uporabo PRESKUSNIH OBJEKTOV in metod, določenih v tem dokumentu. Ta dokument opisuje tudi metode za izračun SSDE in DW, ki predstavljata povprečni vrednosti SSDE(z) in DW(z) na DOLŽINI REKONSTRUKCIJE.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
01-januar-2020
Metode za izračun doze obsevanja glede na velikost obsevanca (SSDE) pri
računalniški tomografiji (IEC 62985:2019)
Methods for calculating Size Specific Dose Estimate (SSDE) on Computed Tomography
(IEC 62985:2019)
Verfahren für die Berechnung größenspezifischer Dosisschätzungen (SSDE) für die
Computertomographie (IEC 62985:2019)
Méthodes de calcul de l’estimateur de dose morphologique (SSDE) en
tomodensitométrie (IEC 62985:2019)
Ta slovenski standard je istoveten z: EN IEC 62985:2019
ICS:
11.040.50 Radiografska oprema Radiographic equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 62985
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2019
ICS 11.040.50
English Version
Methods for calculating size specific dose estimates (SSDE) on
computed tomography
(IEC 62985:2019)
Méthodes de calcul de l’estimateur de dose morphologique Verfahren für die Berechnung größenspezifischer
(SSDE) en tomodensitométrie Dosisschätzungen (SSDE) für die Computertomographie
(IEC 62985:2019) (IEC 62985:2019)
This European Standard was approved by CENELEC on 2019-10-18. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62985:2019 E
European foreword
The text of document 62B/1133/FDIS, future edition 1 of IEC 62985, prepared by SC 62B "Diagnostic
imaging equipment" of IEC/TC 62 "Electrical equipment in medical practice" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN IEC 62985:2019.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2020-07-18
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2022-10-18
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 62985:2019 was approved by CENELEC as a European
Standard without any modification.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC/TR 60788 2004 Medical electrical equipment - Glossary of - -
defined terms
IEC 60601-1 2005 Medical electrical equipment - Part 1: EN 60601-1 2006
General requirements for basic safety and
essential performance
+ A1 2012 + A1 2013
- - + A12 2014
IEC 60601-1-3 2008 Medical electrical equipment - Part 1-3: EN 60601-1-3 2008
General requirements for basic safety and
essential performance - Collateral
Standard: Radiation protection in
diagnostic X-ray equipment
- - + A11 2016
IEC 60601-2-44 2009 Medical electrical equipment - Part 2-44: EN 60601-2-44 2009
Particular requirements for the basic safety
and essential performance of X-ray
equipment for computed tomography
- - + A11 2011
IEC 62985 ®
Edition 1.0 2019-09
INTERNATIONAL
STANDARD
Methods for calculating size specific dose estimates (SSDE) for computed
tomography
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 11.040.50 ISBN 978-2-8322-7290-9
– 2 – IEC 62985:2019 © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Verification of method used to calculate D (z) . 9
W
4.1 General . 9
4.2 Characteristics of the water PHANTOMS . 9
4.3 Characteristics of the anthropomorphic PHANTOM . 10
4.4 Generation of D (z) for the water PHANTOMS . 10
W,REF
4.5 Verification of D for the water PHANTOMS . 10
W,REF
4.6 Generation of D for the water PHANTOMS . 10
W,IMP
4.7 Verification of D (z) against D (z) for the water PHANTOMS . 11
W,IMP W,REF
4.8 Generation of D (z) for the anthropomorphic PHANTOM. 11
W,REF
4.9 Generation of D (z) for the anthropomorphic PHANTOM . 12
W,IMP
4.10 Verification of D (z) against D (z) for the anthropomorphic
W,IMP W,REF
PHANTOM . 12
5 Requirements and limitations . 12
5.1 Calculation of SSDE and D for CT SCANNERS and RDIMS . 12
W
5.2 Pre-scan display of SSDE for CT SCANNERs . 12
5.3 Post-scan updating of SSDE and D for CT SCANNERS . 12
W
5.4 Pre and post-scan display of SSDE and D for CT SCANNERS . 13
W
5.5 Post-scan recording of SSDE and D for CT SCANNERS . 13
W
5.6 Limitations of calculation and display of SSDE and D . 13
W
5.7 Requirements for identification of limitations in the ACCOMPANYING
DOCUMENTS . 13
5.8 Updating SSDE conversion factors, ƒ . 14
Annex A (normative) SSDE conversion factors . 15
A.1 Clarification regarding the use of effective diameter versus D . 15
W
A.2 Equation for determination of SSDE conversion factor . 15
Annex B (normative) Language regarding the general limitations of the SSDE
methodology for use in the ACCOMPANYING DOCUMENTS . 17
Annex C (informative) Estimates of the magnitude of uncertainties from special clinical
scenarios . 18
C.1 General . 18
C.2 Neck included in scanned anatomy . 18
C.3 Range of scan projection radiograph exceeded . 18
C.4 Single or bilateral extremities scanned . 18
C.5 PATIENT not positioned at the centre of rotation along the source/detector
direction . 19
C.6 PATIENT anatomy outside the scan field of view . 19
C.7 Foreign objects within the scanned projection radiograph or scan volume . 19
Bibliography . 20
Index of defined terms used in this document . 21
IEC 62985:2019 © IEC 2019 – 3 –
Figure A.1 – Visualization of ƒ(D ) versus D for the body and head parameters
w W
provided in Table A.1 . 16
Table 1 – Anthropomorphic PHANTOM regions to be scanned . 11
Table A.1 – SSDE Conversion factor as a function of D . 15
W
– 4 – IEC 62985:2019 © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
METHODS FOR CALCULATING SIZE SPECIFIC DOSE
ESTIMATES (SSDE) FOR COMPUTED TOMOGRAPHY
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of th
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.