1、 STD-ES1 ES EN b1953-ENGL 1998 1b24bL9 Ob92783 841 BRITISH STANDARD Diagnostic X-ray imaging equipment - Characteristics of mammographic antimatter grids The European Standard EN 61953 : 1997 has the status of a British Standard ICs 11.040.50 BS EN 61953 : 1998 IEC 61953 : 1997 NO COPYING WITHOUT BS
2、I PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW STD=BSI BS EN bL953-ENGL 1998 Lb24bb9 Ob92784 788 BS EN 61963 : 1998 AmdNo. Date This Brijsh Standard, having been prepared under the direction of the Health and Environment Sector Board, was pubiished under the authority of the Standards Board and c
3、omes into effect on 15 April 1998 Textaffected Q BSI 1998 ISBN O 080 2 - monitor related intedonal and European developments and promuigate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. From 1 January 1997, ali IEC publicaons have
4、the number 60000 added to the old number. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiem from both systems. Cross-references Attention is drawn to the fact that CEN and
5、 CENELEC standards normally include an annex which iists nonnative references to internationai publications with their corresponding European publications. The British Stan- which implement inkrnationai or European publications referred to in this document may be found in the BSI Standards Cataiogue
6、 under the section entitled Intemationai Standards Correspondence Index, or by using the Find facility of the BSI Standarcls Electsonic Cdogue. Additional information. The following print types are used in this standard Requirements, with which compliance can be tested, and definitions: in roman typ
7、e. Explanations, advice, general statements, exceptions and references: in small roman type. Test procedures: in ital2c type. Teims dened in BS 5724 : Part 1 or in BS 6641 : SMALL CAPITAIS. Compliance with a British Standard does not of itself confer immunity from legal obigations. Summary of pages
8、This document comprises a front cover, an inside front cover, the EN titie page, pages 2 to 22, an inside back cover and a back cover. STD-ES1 BS EN bJ953-ENGL I1998 9 Lb24bb9 Ob92785 614 9 EUROPEAN STANDARD EN 61953 NORME EUROPENNE EUROPAISCHE NORM January 1998 ICs 11.040.60 English version Diagnos
9、tic X-ray imaging equipment Characteristics of mammographic anti-scatter grids (IEC 61 953:1997) Appareils dimagerie de diagnostic rayonnement X - Caractristiques des grilles antidiffusantes pour la mammographie Mammographie (CE1 61 953:1997) Bildgebende Gerte fr die Rntgendiagnostik - Kenngren von
10、Streustrahler-Rastern fr die (IEC 61 953: 1997) This European Standard was approved by CENELEC on 1997-07-01. CENELEC members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any a
11、lteration. Up-to-date lists and bibliographcal references concerning such nationai standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by
12、 translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committew of Austria, Belgium, Czech Repubh, Denmark, Finland, France, Germany, Gree
13、ce, Iceland. Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat:
14、 rue de Stassart 35, B - 1050 Bnissels 1998 CENELEC - All right? of exploitation in any farm and by any meana reserved worldwide for CENELEC members. Ref. No. EN 61 953:1998 E - STD-BSI BS EN blI953-ENGL 1998 lIb2Yb69 O692786 550 W Page 2 EN 61963 : 1998 Foreword The text of document 626/297/FOIS, f
15、uture edition 1 of IEC 61953, prepared by SC 628, Diagnostic imaging equipment, of IEC TC 62, Electrical equipment in medical practice, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61 953 on 1997-07-01. The following dates were fixed: - latest date by which the EN
16、 has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 1 998-07-01 - latest date by which the national standards conflicting with the EN have to be withdrawn (daw) 1998-07-01 Annexes designated “normative“ are part of the body of the standar
17、d. Annexes designated “informative“ are given for information only. In this standard, annexes A, B and ZA are normative and annex C is informative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Standard IEC 61953:1997 was approved by CENELEC as a European Stand
18、ard without any modification. STD-BSI BS EN bL953-ENGL 1998 m Lb2Ybb9 Ob92787 497 m Page 3 * rn * EN 61953 : 1998 CONTENTS Page INTRODUCTION . . 4 Clause 1 2 3 4 5 6 Scope and object :., 5 Normative references . . . . . . . . . . . . . . . . . . . . . . . . 5 Terminology . 6 3.1 Degree of requiremen
19、ts . . 6 3.2 Use of terms 6 3.3 Defined terms . 6 Structure Of MAMMOGRAPHIC ANTI-SCATTER GRIDS 8 Measurement and determination of physical characteristics . . . . . . . . . 8 5.1 Method and arrangement for measurement . 8 5.2 Physical characteristics . 10 12 6.1 Manufacturing tolerances . . . . . .
20、. . . . , 12 6.3 Accuracy of characteristics 12 12 6.5 Statement of compliance : 13 Requirements for MAMMOGRAPHIC ANTI-SCATTER GRIDS . . . . . . . . . . . . . 6.2 8termnatOn of the APPLICATION LIMKS 12 6.4 Marking and ACCOMPANYING DOCUMENTS . Figures 1 3 4 Structure of MAMMOGRAPHIC ANTI-SCATTER GRID
21、S . 14 15 Measurement arrangement for MAMMOGRAPHIC ANTI-SCATTER GRIDS with NARROW BEAM CONDITION 16 Measurement arrangement for MAMMOGRAPHIC ANTI-SCAUER GRIDS with 2 RADIATION DETECTOR BROAD BEAM CONDITION .,.,. . . . . . . . . . . . . . . . . 17 Annexes 18 19 B Terminology - Index of defined terms
22、. . 21 C Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ZA Normative references to international publications with their corresponding European publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . .
23、 . . . . . . . . . . . , . . . . . . . 22 A Calculation of the APPLICATION LIMITS . Page 4 EN 61963 : 1998 INTRODUCTION X-ray mammography is an examination which is technically demanding because of the need to achieve high contrast and excellent resolution whilst limiting the absorbed dose to the fe
24、male breast. Low energy X-rays, compression and a special geometry are needed to achieve these objectives. Therefore, only dedicated X-RAY EQUIPMENT should be used. While most of such are not covered by IEC 60627. equipment inCOrp0teS an ANTI-SCATTER GRID, the MAMMOGRAPHIC ANTI-SCATTER GRIDS used AN
25、TI-SCATTER GRIDS used in general radiology are covered by IEC 60627, and this standard follows the same outline. During the writing of this standard, it became clear that a revision of IEC 60627 was necessary, and work on this has started. It is intended that the two standards covering ANTI-SCATTER
26、GRIDS will be merged together. To facilitate this, some subclauses are not used here and extra subclauses have been introduced. Some of the differences between IEC 60627 and this standard are outlined below. - The concept of a reference grid is now omitted. It was found that such grids were little p
27、rocedure. - The geometry used here simulates a typical mammography examination. used. It should be sufficient to unambiguously define the RADIATION DETECTOR and - Only One PHANTOM is used for maSUrementS Of TRANSMISSION OF PRIMARY RADIATION and TRANSMISSION OF SCATTERED RADIATION. - The FLUORESCENT
28、SCREEN used for the measurements employs a thinner calcium tungstate phosphor. This is not a standard mammography phosphor, but this material is well defined, resulting in better uniformity of performance between different screens. - The APPLICATION LIMITS needed to be reduced for mammography. - The
29、 production tolerances have been narrowed, compared to the grids used in general radiology, in order to have meaningful characteristic data which allow the distinction between different grid types used in mammography. Consequently, the measuring tolerances have also been narrowed. Special laboratory
30、 equipment and carefully controlled test conditions are needed for the measurements described here. Page 5 EN 61963 : 1998 STD-BSI BS EN bl1953-ENGL 1998 W Lb24bb9 Ob92787 2bT W DIAGNOSTIC X-RAY IMAGING EQUIPMENT - Characteristics of mammographic anti-scatter grids 1 Scope and object This Internatio
31、nal Standard deals with the definitions, determinations and indication of equipment, in order to reduce the incidence of SCATTERED RADIATION, produced particularly in characteristics of MAMMOGRAPHIC ANTI-SCATTER grids used in diagnostic X-ray imaging the body of the PATIENT, upon the IMAGE RECEPTION
32、 area and thus to improve the contrast of the X-RAY PATTERN. At present only focused ANTI-SCATTER grids are used in mammography. The scope of this standard is therefore restricted to FOCUSED GRIDS. This standard is not intended to be applied for ACCEPTANCE TESTS. This standard does not cover the hom
33、ogeneity of performance over the area of a grid. This standard is not intended to be applied for the determination of the characteristics of installations of X-RAY EQUIPMENT at the USERS site. MAMMOGRAPHIC ANTI-SCATTER GRIDS under conditions Which can normally be found in 2 Normative references The
34、following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this Intern
35、ational Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents listed below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 6041 7: 1973, Graphical symbols for use on equipment. Index, survey a
36、nd compilation of the single sheets IEC 60417N: (1995), Thirteenth supplement IEC 60601 -1 : 1988, Medical electrical equipment - Part 1: General requirements for safety Amendment 1 (1991) Amendment 2 (1995) IEC 60627: 1978, Characteristics of anti-scatter grids used in X-ray equipment IEC 60788: 19
37、84, Medical radiology - Terminology IEC 61 223-1 : 1993, Evaluation and routine testing in medical imaging departments - Part 1: General aspects IEC 61267: 1994, Medical diagnostic X-ray equipment - Radiation conditions for use in the determination of characteristics STD.BSI BS EN 61953-ENGL 1998 =
38、1624bb9 Ob92790 T81 m Page 6 EN 61963 : 1998 3 Terminology 3.1 Degree of requirements In this standard, certain terms which are not printed in SMALL CAPITALS have particular meanings, as follows: - “shall“ indicates a requirement that is mandatory for compliance; - “should“ - may“ - “specificu indic
39、ates a strong recommendation that is not mandatory for compliance; indicates a permitted manner of complying with a requirement or of avoiding the need to comply; is used to indicate definitive information stated in this standard or referenced in other standards, usually concerning particular operat
40、ing conditions, test arrangements or values connected with compliance; - “specified“ is used to indicate definitive information stated by the MANUFACTURER in equipment under consideration, usually concerning its intended purposes, or the parameters or conditions associated with its use or with testi
41、ng to determine compliance. ACCOMPANYING DOCUMENTS or in other documentation relating to the 3.2 Use of terms In this standard, terms printed in SMALL CAPITALS are used as defined in IEC 60601-1, in IEC 60788, in clause 3 of this standard or in other standards referenced in annex B. 3.3 Defined term
42、s For the purpose of this International Standard, the following definitions apply. NOTE - Some of the defined terms given in this standard deviate from those given in the Cullent edition (1984) of IEC 60788. II . 3.3.1 ANTI-SCATTER GRID: Device with a fixed periodic arrangement of materials with dif
43、ferent reduce the incidence of SCATTERED RADIATION upon that afea and thus increase the Contrast in X-ray ATTENUATION properties to be placed in front Of the IMAGE RECEPTION AREA in order to the X-RAY PATTERN. 3.3.2 LINEAR GRID: ANTI-SCATTER GRID composed of highly absorbing strips and highly transm
44、itting interspaces which are parallel in their longitudinal direction. 3.3.3 Not used. 3.3.4 FOCUSED GRID: LINEAR GRID in which the planes of the absorbing strips converge to a straight line at the FOCUSING DISTANCE. 3.3.5 Not used. 3.3.6 Not used. 3.3.7 STATIONARY GRID: ANTI-SCATTER GRID used in su
45、ch a way that it does not move in relation to the RADIATION BEAM. - STD-BSI BS EN b39.53-ENGL 3998 3b24bb9 Ob92793 938 Page7 EN 61963 : 1998 3.3.8 MOVING GRID: ANTI-SCATTER GRID used in an ACCESSORY that enables the ANTI-SCATTER GRID to be moved, when irradiated by a RADIATION BEAM, in order to avoi
46、d the imaging of the absorbing strips and the consequent loss of information. 3.3.9 MAMMOGRAPHIC ANTI-SCATTER GRID: FOCUSED GRID Specially designed for mammography. 3.3.1 O Geometric characteristics 3.3.10.1 STRIP FREQUENCY: Letter symbol: N, unit: cm-1. Number of absorbing strips per unit length Of
47、 a LINEAR GRID. NOTE - This term replaces the previous term “STRIPS PER CENTIMETRE. 3.3.10.2 GRID RATIO: Letter symbol: r. Ratio between the height of the absorbing strips and the distance between the absorbing strips in the centre of a LINEAR GRID. 3.3.1 0.3 FOCUSING DISTANCE: Letter symbol: fo, un
48、it: cm. Distance between the incident face of a FOCUSED GRID and the line into which the planes of the absorbing strips of the grid converge. NOTE - Attention is drawn to the differences between FOCUSING DISTANCE“, “FOCAL SPOT to grid distance“ and FOCAL SPOT to film distance“. 3.3.10.4 APPLICATION
49、LIMITS: Letter symbols: f, f2, unit: cm. Lower, f, and upper, f2, limits of the distance from the FOCAL SPOT to the incident face of a FOCUSED GRID between which the obtained radiological information can generally be expected to be acceptable. 3.3.10.5 TRUE CENTRAL LINE: Perpendicular projection onto the incident face of a FOCUSED GRID of the line into which the planes of the absorbing strips converge. 3.3.10.6 intended to indicate the position and direction of the TRUE CENTRAL LINE. CENTRAL LINE INDICATION: On the incid
