SIST EN 61675-2:2016

Radionuclide imaging devices - Characteristics and test conditions - Part 2: Gamma cameras for planar imaging and spect imaging (IEC 61675-2:2015)

This part of IEC 61675 specifies terminology and test methods for describing the characteristics
of GAMMA CAMERAS equipped with PARALLEL HOLE COLLIMATORS for planar imaging.
Additional tests are specified for those GAMMA CAMERAS that are capable of planar wholebody
imaging (PLANAR WHOLEBODY IMAGING EQUIPMENT) or SINGLE PHOTON EMISSION COMPUTED
TOMOGRAPHY (SPECT). These GAMMA CAMERAS consist of a gantry, single or multiple DETECTOR
HEADS, and a computer for data acquisition, processing, storage, and display. The DETECTOR
HEADS may contain single or multiple scintillation crystals or solid state detectors.
No test has been specified to characterize the uniformity of reconstructed images because all
methods known so far will mostly reflect the noise of the image.

Bildgebende Systeme in der Nuklearmedizin - Merkmale und Prüfbedingungen - Teil 2: Gammakameras für planare Bildgebung, mit Ganzkörper-Zusatz und Gammakameras zur Einzelphotonen-Emissions-Tomographie (SPECT)

Dispositifs d'imagerie par radionucléides - Caractéristiques et conditions d'essai - Partie 2: gamma caméras pour l'imagerie planaire et l'imagerie spect

L'IEC 61675-2:2015 spécifie la terminologie et les méthodes d'essai relatives à la description des caractéristiques des gamma-caméras équipées de collimateurs à trous parallèles pour l'imagerie planaire. Cette seconde édition de l'IEC 61675-2 annule et remplace la première édition publiée en 1998 et son Amendement 1 publié en 2004, ainsi que l'IEC 60789:2005, l'IEC 60789:2005/COR1:2009, et l'IEC 61675-3:1998. Elle a fait l'objet d'un reformatage, d'une mise à jour et d'un alignement partiel avec le document NEMA NU 1-2007.

Naprave za opazovanje radioaktivnih elementov - Karakteristike in preskusni pogoji - 2. del: Gama kamere za planarno slikanje in slikanje SPECT (IEC 61675-2:2015)

Ta del standarda IEC 61675 določa terminologijo in preskusne metode za opisovanje karakteristik GAMA KAMER, opremljenih s KOLIMATORJI Z VZPOREDNIMI LUKNJAMI za planarno slikanje. Dodatni preskusi so določeni za GAMA KAMERE, ki so zmožne planarnega slikanja celega telesa (OPREMA ZA PLANARNO SLIKANJE CELEGA TELESA) ali ENOFOTONSKE IZSEVNE RAČUNALNIŠKE TOMOGRAFIJE (SPECT). Te GAMA KAMERE so sestavljene iz podstavka, ene ali več GLAV DETEKTORJA in računalnika za pridobivanje, obdelavo, shranjevanje in prikaz podatkov. GLAVE DETEKTORJA lahko vsebujejo enega ali več kristalov za iskrenje ali detektorje v trdnem stanju. Za označevanje enotnosti rekonstruiranih slik ni bil določen noben preskus, ker vse do zdaj znane metode v večini primerov izražajo šum slik.

General Information

• Status: Published
• Publication Date: 08-Feb-2016
• ICS: 11.040.50 - Radiographic equipment
• Technical Committee: IEMO - Electrical equipment in medical practice
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 26-Nov-2015
• Due Date: 31-Jan-2016
• Completion Date: 09-Feb-2016
• Ref Project: EN 61675-2:2015 - Radionuclide imaging devices - Characteristics and test conditions - Part 2: Gamma cameras for planar, wholebody, and SPECT imaging

Relations

• Revised: SIST EN 61675-2:1998/A1:2005 - Radionuclide imaging devices - Characteristics and test conditions -- Part 2: Single photon emission computer tomographs
• Effective Date: 16-Jul-2014
• Revised: SIST EN 61675-2:1998 - Radionuclide imaging devices - Characteristics and test conditions -- Part 2: Single photon emission computer tomographs
• Effective Date: 16-Jul-2014
• Replaces: SIST EN 61675-2:1998/A1:2005 - Radionuclide imaging devices - Characteristics and test conditions -- Part 2: Single photon emission computer tomographs
• Effective Date: 07-Jun-2022

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 61675-2:2016
01-april-2016
1DGRPHãþD
SIST EN 60789:2007
SIST EN 61675-2:1998
SIST EN 61675-2:1998/A1:2005
SIST EN 61675-3:1998
Naprave za opazovanje radioaktivnih elementov - Karakteristike in preskusni
pogoji - 2. del: Gama kamere za planarno slikanje in slikanje SPECT (IEC 61675-
2:2015)
Radionuclide imaging devices - Characteristics and test conditions - Part 2: Gamma
cameras for planar imaging and spect imaging (IEC 61675-2:2015)
Dispositifs d'imagerie par radionucléides - Caractéristiques et conditions d'essai - Partie
2: gamma caméras pour l'imagerie planaire et l'imagerie spect
Ta slovenski standard je istoveten z: EN 61675-2:2015
ICS:
11.040.50 Radiografska oprema Radiographic equipment
SIST EN 61675-2:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 61675-2:2016

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SIST EN 61675-2:2016


EUROPEAN STANDARD EN 61675-2

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2015
ICS 11.040.50 Supersedes EN 60789:2005, EN 61675-2:1998, EN
61675-3:1998
English Version
Radionuclide imaging devices - Characteristics and test
conditions - Part 2: Gamma cameras for planar, wholebody, and
SPECT imaging
(IEC 61675-2:2015)
Dispositifs d'imagerie par radionucléides - Caractéristiques Bildgebende Systeme in der Nuklearmedizin - Merkmale
et conditions d'essai - Partie 2: Gamma-caméras pour und Prüfbedingungen - Teil 2: Gammakameras für planare
l'imagerie planaire, l'imagerie du corps entier et l'imagerie Bildgebung, mit Ganzkörper-Zusatz und Gammakameras
SPECT zur Einzelphotonen-Emissions-Tomographie (SPECT)
(IEC 61675-2:2015) (IEC 61675-2:2015)
This European Standard was approved by CENELEC on 2015-09-10. 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, 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: Avenue Marnix 17, B-1000 Brussels
© 2015 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 61675-2:2015 E

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SIST EN 61675-2:2016
EN 61675-2:2015

European foreword
The text of document 62C/616/FDIS, future edition 2 of IEC 61675-2, prepared by IEC/SC 62C
"Equipment for radiotherapy, nuclear medicine and radiation dosimetry" of IEC/TC 62 "Electrical
equipment in medical practice" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 61675-2:2015.
The following dates are fixed:
(dop) 2016-06-10
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
(dow) 2018-09-10
• latest date by which the national
standards conflicting with the
document have to be withdrawn
This document supersedes EN 61675-2:1998 and A1:2005, EN 60789:2005 and EN 61675-3:1998.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.

Endorsement notice
The text of the International Standard IEC 61675-2:2015 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60601-1:2005 NOTE  Harmonized as EN 60601-1:2006 (not modified).
A1:2012 A1:2013
IEC 61675-1:2013 NOTE  Harmonized as EN 61675-1:2014 (not modified).
2

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EN 61675-2:2015


Annex ZA
(normative)


Normative references to international publications
with their corresponding European publications


The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.


NOTE 1 When 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 61675-1 2013 Radionuclide imaging devices - EN 61675-1 2014
Characteristics and test conditions -- Part
1: Positron emission tomographs

3

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SIST EN 61675-2:2016



IEC 61675-2

®


Edition 2.0 2015-08




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE











Radionuclide imaging devices – Characteristics and test conditions –

Part 2: Gamma cameras for planar, wholebody, and SPECT imaging




Dispositifs d’imagerie par radionucléides – Caractéristiques et conditions

d’essai –

Partie 2: Gamma-caméras pour l'imagerie planaire, l'imagerie du corps entier et


l'imagerie SPECT














INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE


INTERNATIONALE




ICS 11.040.50 ISBN 978-2-8322-2819-7



Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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SIST EN 61675-2:2016
– 2 – IEC 61675-2:2015 © IEC 2015
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions. 7
4 Test methods . 15
4.1 General . 15
4.2 Planar imaging . 16
4.2.1 SYSTEM SENSITIVITY . 16
4.2.2 SPATIAL RESOLUTION . 18
4.2.3 SPATIAL NON-LINEARITY. 24
4.2.4 NON-UNIFORMITY OF RESPONSE . 25
4.2.5 INTRINSIC ENERGY RESOLUTION . 28
4.2.6 Intrinsic MULTIPLE WINDOW SPATIAL REGISTRATION . 29
4.2.7 COUNT RATE performance . 31
4.2.8 Shield leakage test . 33
4.3 Wholebody imaging . 33
4.3.1 Scanning constancy . 33
4.3.2 SPATIAL RESOLUTION without scatter . 36
4.4 Tomographic imaging (SPECT) . 37
4.4.1 Test of PROJECTION geometry . 37
4.4.2 Measurement of SPECT SYSTEM SENSITIVITY . 41
4.4.3 Scatter measurement . 44
4.4.4 SPECT SYSTEM SPATIAL RESOLUTION . 48
4.4.5 Tomographic image quality . 50
5 Accompanying documents . 57
5.1 General . 57
5.2 General parameters for GAMMA CAMERAS . 58
5.2.1 COLLIMATORS . 58
5.2.2 Shield leakage values . 58
5.2.3 Pre-set PULSE AMPLITUDE ANALYSER WINDOWS . 58
5.2.4 INTRINSIC ENERGY RESOLUTION . 58
5.2.5 COLLIMATOR dependent quantities . 58
5.2.6 COUNT RATE CHARACTERISTICS . 58
5.2.7 Measured COUNT RATE that is 80 % of the corresponding TRUE COUNT
RATE . 58
5.2.8 Dimensions of the DETECTOR FIELD OF VIEW . 58
5.2.9 Non-uniformity characteristics . 58
5.2.10 INTRINSIC SPATIAL RESOLUTION (FWHM and EW) of the DETECTOR HEAD
COLLIMATOR . 58
without
5.2.11 INTRINSIC SPATIAL NON-LINEARITY . 58
5.2.12 Intrinsic MULTIPLE WINDOW SPATIAL REGISTRATION . 59
5.3 GAMMA CAMERA based wholebody imaging system . 59
5.3.1 Scanning constancy . 59
5.3.2 SPATIAL RESOLUTION . 59
5.4 SPECT . 59

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5.4.1 Calibration measurements of COR . 59
5.4.2 Measurement of head tilt . 59
5.4.3 Measurement of COLLIMATOR hole misalignment . 59
5.4.4 TRANSVERSE RESOLUTION (radial and tangential) . 59
5.4.5 AXIAL RESOLUTION . 59
5.4.6 Axial PIXEL size . 59
5.4.7 Transaxial PIXEL size . 59
5.4.8 DETECTOR POSITIONING TIME . 59
5.4.9 NORMALIZED VOLUME SENSITIVITY . 59
5.4.10 SCATTER FRACTIONS SF and SF . 59
i
5.4.11 Scan set up and phantom ACTIVITY concentration . 59
5.4.12 Image quality . 59
5.4.13 Accuracy of ATTENUATION correction and scatter correction . 59
5.4.14 Accuracy of SPECT and CT image registration . 59
Index of defined terms . 60
Bibliography . 62

Figure 1 – Geometry of PROJECTIONS . 9
Figure 2 – Cylindrical phantom . 14
Figure 3 – Cuvette . 17
Figure 4 – Slit phantom . 19
Figure 5 – Source arrangement for intrinsic measurements . 20
Figure 6 – Calculation of FWHM . 22
Figure 7 – Evaluation of equivalent width (EW) . 23
Figure 8 – Uniform source . 26
Figure 9 – Small shielded liquid source . 29
Figure 10 – Source positions for scanning constancy for wholebody imaging . 35
Figure 11 – Cylindrical phantom . 43
Figure 12 – Phantom insert with holders for the scatter source . 45
Figure 13 – Evaluation of scatter fraction . 47
Figure 14 – Reporting transverse resolution . 49
Figure 15 – Cross-section of body phantom . 51
Figure 16 – Phantom insert with hollow spheres . 52
Figure 17 – Placement of ROIs in the phantom background . 55

Table 1 – RADIONUCLIDES and ENERGY WINDOWS to be used for performance
measurements . 16

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

RADIONUCLIDE IMAGING DEVICES –
CHARACTERISTICS AND TEST CONDITIONS –

Part 2: Gamma cameras for planar, wholebody,
and SPECT imaging

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 the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61675-2 has been prepared by subcommittee 62C: Equipment for
radiotherapy, nuclear medicine and radiation dosimetry, of IEC technical committee 62:
Electrical equipment in medical practice.
This second edition of IEC 61675-2 cancels and replaces the first edition published in 1998 and
its Amendment 1 published in 2004, as well as IEC 60789:2005, IEC 60789:2005/COR1:2009,
and IEC 61675-3:1998. It has been reformatted, updated, and partly aligned with NEMA NU 1-
2007. Due to the lack of market share of SPECT-systems operated in coincidence mode all
such tests have been removed.

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SIST EN 61675-2:2016
IEC 61675-2:2015 © IEC 2015 – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
62C/616/FDIS 62C/623/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
In this standard, the following print types are used:
– TERMS DEFINED IN CLAUSE 2 OF THIS STANDARD OR LISTED IN THE INDEX OF DEFINED TERMS:
SMALL CAPITALS.
The requirements are followed by specifications for the relevant tests.
Annex A is for information only.
The committee has decided that the contents of this publication will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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INTRODUCTION
The test methods specified in this part of IEC 61675 have been selected to reflect as much as
possible the clinical use of GAMMA CAMERAS for planar imaging, PLANAR WHOLEBODY IMAGING
EQUIPMENT, and SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT). It is intended that
the test methods are carried out by manufacturers thereby enabling them to describe the
characteristics of the systems on a common basis.

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SIST EN 61675-2:2016
IEC 61675-2:2015 © IEC 2015 – 7 –
RADIONUCLIDE IMAGING DEVICES –
CHARACTERISTICS AND TEST CONDITIONS –

Part 2: Gamma cameras for planar, wholebody,
and SPECT imaging



1 Scope
This part of IEC 61675 specifies terminology and test methods for describing the character-
istics of GAMMA CAMERAS equipped with PARALLEL HOLE COLLIMATORS for planar imaging.
Additional tests are specified for those GAMMA CAMERAS that are capable of planar wholebody
imaging (PLANAR WHOLEBODY IMAGING EQUIPMENT) or SINGLE PHOTON EMISSION COMPUTED
TOMOGRAPHY (SPECT). These GAMMA CAMERAS consist of a gantry, single or multiple DETECTOR
HEADS, and a computer for data acquisition, processing, storage, and display. The DETECTOR
HEADS may contain single or multiple scintillation crystals or solid state detectors.
No test has been specified to characterize the uniformity of reconstructed images because all
methods known so far will mostly reflect the noise of the image.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
IEC 60788:2004, Medical electrical equipment – Glossary of defined terms
IEC 61675-1:2013, Radionuclide imaging devices – Characteristics and test conditions –
Part 1: Positron emission tomographs
3 Terms and definitions
For the purposes of this document the terms and definitions given in IEC 60788 and
IEC 61675-1 (some of which are repeated here for convenience), and the following terms and
definitions apply.
3.1
ADDRESS PILE UP
false address calculation of an artificial event which passes the ENERGY
WINDOW, but is formed from two or more events by the PILE UP EFFECT
3.2
AXIAL FIELD OF VIEW
dimensions of a slice through the TOMOGRAPHIC VOLUME parallel to and including the SYSTEM
AXIS
Note 1 to entry: In practice it is specified only by its axial dimension given by the distance between the centres of
the outermost defined IMAGE PLANES plus the average of the measured AXIAL SLICE WIDTH measured as EQUIVALENT
WIDTH (EW).

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3.3
AXIAL RESOLUTION
for tomographs with sufficiently fine axial sampling fulfilling the sampling theorem, SPATIAL
RESOLUTION along a line parallel to the SYSTEM AXIS
3.4
CENTRE OF ROTATION
COR
origin of that coordinate system, which describes the PROJECTIONS of a transverse slice with
respect to their orientation in space
Note 1 to entry: The CENTRE OF ROTATION of a transverse slice is given by the intersection of the SYSTEM AXIS with
the mid-plane of the corresponding OBJECT SLICE.
Note 2 to entry: The second note to entry concerns the French text only.
3.5
COLLIMATOR AXIS
straight line which passes through the geometrical centre of the exit field and entrance field of
the COLLIMATOR
3.6
COLLIMATOR FRONT FACE
surface of the COLLIMATOR which is closest to the object being imaged
3.7
COORDINATE SYSTEM OF PROJECTION
Cartesian system of the IMAGE MATRIX of each two-dimensional PROJECTION with axes X and
p
Y
p
Note 1 to entry: Axes X and Y are defined by the axes of the IMAGE MATRIX.
p p
Note 2 to entry: The Y axis and the PROJECTION of the SYSTEM AXIS onto the detector front face have to be in
p
parallel.
Note 3 to entry: The origin of the COORDINATE SYSTEM OF PROJECTION may be the centre of the IMAGE MATRIX (see
Figure 1).

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IEC
NOTE The FIXED COORDINATE SYSTEM X, Y, Z has its origin at the centre of the TOMOGRAPHIC VOLUME (shown as a
cylinder), the Z-axis being the SYSTEM AXIS. The COORDINATE SYSTEM OF PROJECTION X , Y is shown for a
p p
PROJECTION ANGLE θ. For each θ, the one-dimensional PROJECTION of the marked OBJECT SLICE has the address
range shown (hatched). Within this range the CENTRE OF ROTATION is projected onto the address X (offset).
p
Figure 1 – Geometry of PROJECTIONS
3.8
COUNT LOSS
difference between measured COUNT RATE and TRUE COUNT RATE, which is caused by the finite
RESOLVING TIME of the instrument
[SOURCE: IEC 61675-1:2013, 3.8.1]
3.9
COUNT RATE
number of counts per unit of time
[SOURCE: IEC 61675-1:2013, 3.8.2]
3.10
COUNT RATE CHARACTERISTIC
COUNT RATE and TRUE COUNT RATE
function giving the relationship between observed

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[SOURCE: IEC 60788:2004, rm-34-21]
3.11
DETECTOR FIELD OF VIEW
FOV
region of the detector within which events are included in the display image, and for which all
performance specifications are provided
Note 1 to entry: The note to entry regarding the abbreviation concerns the French text only.
3.12
DETECTOR HEAD TILT
deviation of the COLLIMATOR AXIS from orthogonality with the SYSTEM AXIS
3.13
DETECTOR POSITIONING TIME
fraction of the total time spent on an acquisition which is not used in collecting data
3.14
EMISSION COMPUTED TOMOGRAPHY
ECT
imaging method for the representation of the spatial distribution of RADIONUCLIDES in selected
two-dimensional slices through the object
3.15
ENERGY WINDOW
range defining the energy signals accepted by the device for further processing
3.16
EQUIVALENT WIDTH
EW
width of that rectangle having the same area and the same height as the response function,
e.g. the POINT SPREAD FUNCTION
[SOURCE: IEC 60788:2004, rm-34-45]
3.17
FIXED COORDINATE SYSTEM
Cartesian system with axes X, Y, and Z
Note 1 to entry: Z being the SYSTEM AXIS.
Note 2 to entry: The origin of the FIXED COORDINATE SYSTEM is defined by the centre of the TOMOGRAPHIC VOLUME
(see Figure 1).
Note 3 to entry: The SYSTEM AXIS is orthogonal to all transverse slices.
3.18
IMAGE MATRIX
arrangement of MATRIX ELEMENTS in a preferentially Cartesian coordinate system
3.19
IMAGE PLANE
plane assigned to a plane in the OBJECT SLICE
Note 1 to entry: Usually the IMAGE PLANE is the mid-plane of the corresponding OBJECT SLICE.

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3.20
INTRINSIC ENERGY RESOLUTION
FULL WIDTH AT HALF MAXIMUM of the full energy absorption peak in the INTRINSIC ENERGY
SPECTRUM for a specified RADIONUCLIDE
3.21
INTRINSIC ENERGY SPECTRUM
measured histogram of pulse heights for the DETECTOR HEAD without COLLIMATOR
Note 1 to entry: The pulse height should be expressed as corresponding energy.
3.22
INTRINSIC NON-UNIFORMITY OF RESPONSE
NON-UNIFORMITY OF RESPONSE of the DETECTOR HEAD without COLLIMATOR
3.23
INTRINSIC SPATIAL NON-LINEARITY
SPATIAL NON-LINEARITY of the DETECTOR HEAD without COLLIMATOR
3.24
INTRINSIC SPATIAL RESOLUTION
SPATIAL RESOLUTION in air for a specified RADIONUCLIDE measured without the
COLLIMATOR
3.25
LINE SOURCE
straight RADIOACTIVE SOURCE approximating a δ-function in two dimensions and being constant
(uniform) in the third dimension
3.26
MATRIX ELEMENT
smallest unit of an IMAGE MATRIX, which is assigned in location and size to a certain volume
element of the object (VOXEL)
3.27
MULTIPLE WINDOW SPATIAL REGIS
...