Dedicated Radionuclide Imaging Devices - Characteristics and Test Conditions - Part 1: Cardiac SPECT (IEC 63073-1:2020)

This document specifies terminology and test methods for describing the characteristics of
SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT) systems designed specifically for
tomographic cardiac imaging. This includes dedicated systems or general purpose systems with
dedicated sub-systems which are not included in the scope of IEC 61675-2.

Spezielle Radionuklid-Bildgebungsgeräte - Merkmale und Prüfbedingungen - Teil 1: Kardiale SPECT (IEC 63073-1:2020)

Dispositifs d'imagerie par radionucléides dédiés - Caractéristiques et conditions d'essai - Partie 1: SPECT pour scintigraphie cardiaque (IEC 63073-1:2020)

L'IEC 63073-1:2020 spécifie la terminologie et les méthodes d'essai relatives à la description des caractéristiques des systèmes de TOMODENSITOMETRIE PAR EMISSION DE PHOTONS SIMPLES (SPECT) conçus spécifiquement pour l’imagerie cardiaque tomographique. Ceci inclut les systèmes dédiés aussi bien que les systèmes génériques équipés de sous-systèmes dédiés qui ne relèvent pas du domaine d'application de l’IEC 61675-2.

Namenske naprave za slikanje z radionuklidi - Karakteristike in preskusni pogoji - 1. del: Preiskava srca SPECT (IEC 63073-1:2020)

General Information

Status
Published
Publication Date
14-Dec-2020
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
11-Dec-2020
Due Date
15-Feb-2021
Completion Date
15-Dec-2020

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SLOVENSKI STANDARD
SIST EN IEC 63073-1:2021
01-februar-2021

Namenske naprave za slikanje z radionuklidi - Karakteristike in preskusni pogoji -

1. del: Preiskava srca SPECT (IEC 63073-1:2020)

Dedicated Radionuclide Imaging Devices - Characteristics and Test Conditions - Part 1:

Cardiac SPECT (IEC 63073-1:2020)
Spezielle Radionuklid-Bildgebungsgeräte - Merkmale und Prüfbedingungen - Teil 1:
Kardiale SPECT (IEC 63073-1:2020)

Dispositifs d'imagerie par radionucléides dédiés - Caractéristiques et conditions d'essai -

Partie 1: SPECT pour scintigraphie cardiaque (IEC 63073-1:2020)
Ta slovenski standard je istoveten z: EN IEC 63073-1:2020
ICS:
11.040.50 Radiografska oprema Radiographic equipment
SIST EN IEC 63073-1:2021 en

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

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SIST EN IEC 63073-1:2021
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SIST EN IEC 63073-1:2021
EUROPEAN STANDARD EN IEC 63073-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2020
ICS 11.040.50
English Version
Dedicated radionuclide imaging devices - Characteristics and
test conditions - Part 1: Cardiac SPECT
(IEC 63073-1:2020)

Dispositifs d'imagerie par radionucléides dédiés - Spezielle Radionuklid-Bildgebungsgeräte - Merkmale und

Caractéristiques et conditions d'essai - Partie 1: SPECT Prüfbedingungen - Teil 1: Kardiale SPECT

pour scintigraphie cardiaque (IEC 63073-1:2020)
(IEC 63073-1:2020)

This European Standard was approved by CENELEC on 2020-11-30. 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

© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN IEC 63073-1:2020 E
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SIST EN IEC 63073-1:2021
EN IEC 63073-1:2020 (E)
European foreword

The text of document 62C/740/CDV, future edition 1 of IEC 63073-1, prepared by 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 IEC 63073-1:2020.
The following dates are fixed:

• latest date by which the document has to be implemented at national (dop) 2021-08-30

level by publication of an identical national standard or by endorsement

• latest date by which the national standards conflicting with the (dow) 2023-11-30

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 63073-1:2020 was approved by CENELEC as a European

Standard without any modification.
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SIST EN IEC 63073-1:2021
EN IEC 63073-1:2020 (E)
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 61675-2 2015 Radionuclide imaging devices - EN 61675-2 2015
Characteristics and test conditions - Part 2:
Gamma cameras for planar, wholebody,
and SPECT imaging
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SIST EN IEC 63073-1:2021
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SIST EN IEC 63073-1:2021
IEC 63073-1
Edition 1.0 2020-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Dedicated radionuclide imaging devices – Characteristics and test conditions –
Part 1: Cardiac SPECT
Dispositifs d'imagerie par radionucléides dédiés – Caractéristiques et
conditions d'essai –
Partie 1: SPECT pour scintigraphie cardiaque
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 11.040.50 ISBN 978-2-8322-8967-9

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 IEC 63073-1:2021
– 2 – IEC 63073-1:2020 © IEC 2020
CONTENTS

CONTENTS ............................................................................................................................ 2

FOREWORD ........................................................................................................................... 3

INTRODUCTION ..................................................................................................................... 5

1 Scope .............................................................................................................................. 6

2 Normative references ...................................................................................................... 6

3 Terms and definitions ...................................................................................................... 6

4 Test methods ................................................................................................................... 7

4.1 General ................................................................................................................... 7

4.2 Detector characteristics .......................................................................................... 8

4.2.1 General ........................................................................................................... 8

4.2.2 Energy resolution and LOW-ENERGY-TAIL RATIO measurement ........................... 8

4.2.3 Shield leakage ................................................................................................. 9

4.2.4 COUNT RATE performance ............................................................................... 10

4.2.5 System sensitivity .......................................................................................... 12

4.2.6 Non-uniformity for each CARDIAC DETECTOR HEAD ........................................... 14

4.2.7 SCATTER FRACTION ......................................................................................... 14

4.3 Characteristics of tomographic images .................................................................. 16

4.3.1 CENTRE OF ROTATION (COR) ........................................................................... 16

4.3.2 REFERENCE POINT localization in the reconstructed FOV ................................. 16

4.3.3 Accuracy of tomographic system sensitivity modelling ................................... 17

4.3.4 Tomographic SPATIAL NON-LINEARITY............................................................... 19

4.3.5 Tomographic SPATIAL RESOLUTION .................................................................. 21

4.3.6 Image quality assessment using a heart phantom .......................................... 23

5 Additional testing ........................................................................................................... 26

6 ACCOMPANYING DOCUMENTS ............................................................................................ 27

Bibliography .......................................................................................................................... 28

Index of defined terms .......................................................................................................... 29

Figure 1 – Small shielded liquid source ................................................................................. 10

Figure 2 – Transverse slice of phantom used for measuring COUNT RATE performance .......... 11

Figure 3 – Evaluation of SCATTER FRACTION ........................................................................... 15

Figure 4 – Calculation of FWHM and measurement of the location of the maximum

value..................................................................................................................................... 17

Figure 5 – Transaxial view of the 7 LINE SOURCE Phantom ..................................................... 18

Figure 6 – Transaxial view of the 7 LINE SOURCE phantom centred within a 140 mm

diameter water-filled cylinder ................................................................................................ 22

Figure 7 – Placement of ROIs in SHORT AXIS view of myocardium .......................................... 25

Figure 8 – Placement of ROIs in LONG AXIS view of myocardium ............................................ 26

Table 1 – Relative ACTIVITY concentration of compartments of the anthropomorphic

phantom ............................................................................................................................... 24

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IEC 63073-1:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
DEDICATED RADIONUCLIDE IMAGING DEVICES –
CHARACTERISTICS AND TEST CONDITIONS –
Part 1: Cardiac SPECT
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 63073-1 has been prepared by subcommittee 62C: Equipment for

radiotherapy, nuclear medicine and radiation dosimetry, of IEC technical committee 62:

Electrical equipment in medical practice.
The text of this document is based on the following documents:
CDV Report on voting
62C/740/CDV 62C/765/RVC

Full information on the voting for the approval of this document can be found in the report on

voting indicated in the above table.

This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

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SIST EN IEC 63073-1:2021
– 4 – IEC 63073-1:2020 © IEC 2020
In this document, the following print types are used:

– terms defined in Clause 3 of this document or listed in the index of defined terms:

SMALL CAPITALS.
The requirements are followed by specifications for the relevant tests.

A list of all parts in the IEC 63073 series, published under the general title Dedicated

radionuclide imaging devices – Characteristics and test condtions, can be found on the IEC

website.

The committee has decided that the contents of this document will remain unchanged until the

stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to

the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates that it

contains colours which are considered to be useful for the correct understanding of its

contents. Users should therefore print this document using a colour printer.
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SIST EN IEC 63073-1:2021
IEC 63073-1:2020 © IEC 2020 – 5 –
INTRODUCTION

The test methods specified in this part of IEC 63073 have been selected to reflect as much as

possible the clinical use of GAMMA CAMERAS that are dedicated to cardiac 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 IEC 63073-1:2021
– 6 – IEC 63073-1:2020 © IEC 2020
DEDICATED RADIONUCLIDE IMAGING DEVICES –
CHARACTERISTICS AND TEST CONDITIONS –
Part 1: Cardiac SPECT
1 Scope

This document specifies terminology and test methods for describing the characteristics of

SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY (SPECT) systems designed specifically for

tomographic cardiac imaging. This includes dedicated systems or general purpose systems with

dedicated sub-systems which are not included in the scope of IEC 61675-2.
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.

IEC 61675-2:2015, Radionuclide imaging devices – Characteristics and test conditions – Part 2:

Gamma cameras for planar, wholebody, and SPECT imaging
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

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

addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
REFERENCE POINT

defined 3D position in the FOV of the camera, specified by the manufacturer, or, if not specified

by the manufacturer, assumed to be the centre of the FOV of the camera
3.2
BAD PIXEL

detector pixel that has been physically or electronically turned off such that gamma rays which

interact in that BAD PIXEL are not recorded by the camera
3.3
CARDIAC DETECTOR HEAD
assembly of detector components associated with a single COLLIMATOR
3.4
CARDIAC DETECTOR HEAD ELEMENT

smallest discrete unit of the CARDIAC DETECTOR HEAD that is able to provide distinct energy,

spatial, and timing information about detected photons
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IEC 63073-1:2020 © IEC 2020 – 7 –
3.5
CCFOV

central volume of the field of view of a cardiac camera, located within a radius of 7 cm from the

REFERENCE POINT
3.6
CUFOV

field of view of a cardiac camera for which the summed counts for a LINE SOURCE segment are

at least 50 % of the summed counts measured with the camera with the LINE SOURCE segment

positioned within the CCFOV
3.7
CARDIAC ORIENTATION
image coordinate system specified in reference to the axes of the heart
3.8
SHORT AXIS

in the CARDIAC ORIENTATION, the plane perpendicular to the long-axis of the heart

3.9
LONG AXIS
in the CARDIAC ORIENTATION, a plane parallel to the long-axis of the heart
3.10
HORIZONTAL LONG AXIS
HLA

in the CARDIAC ORIENTATION, the LONG AXIS plane that most closely bisects both the left ventricle

and the right ventricle of the heart
3.11
VERTICAL LONG AXIS
VLA

in the CARDIAC ORIENTATION, the LONG AXIS plane, that is perpendicular to the HORIZONTAL LONG

AXIS
3.12
LOW-ENERGY-TAIL RATIO

ratio of the counts measured in an ENERGY WINDOW Of width 2 × E centred at energy E

FWHM peak

– 2 × E divided by the counts measured in an ENERGY WINDOW Of width 2 × E centred

FWHM FWHM

at an energy of E , where E is the peak energy of the radioisotope being measured and

peak peak
E is the energy resolution of the detector
FWHM
4 Test methods
4.1 General

Before the measurements are performed, the tomographic system shall be adjusted by the

procedure normally used by the manufacturer for an installed unit and shall not be adjusted

specially for the measurement of specific parameters. If any test cannot be carried out exactly

as specified in the standard, the reason for the deviation and the exact conditions under which

the test was performed shall be stated clearly.

Unless otherwise specified, each CARDIAC DETECTOR HEAD in the system shall be characterized

by a full data set.
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Unless otherwise specified, SPECT characterization shall be provided for an acquisition

covering the minimal rotation required to obtain a complete set of data (e.g. 120° for a three-

headed rotating-gantry system). If a rotating-gantry tomograph is specified to operate in a non-

circular orbiting mode influencing the performance parameters, test results for the non-circular

orbiting mode shall be reported in addition.

Unless otherwise specified, measurements are carried out at COUNT RATES not exceeding

40 000 counts per second on each CARDIAC DETECTOR HEAD and not exceeding 120 000 counts

per second for the system.
4.2 Detector characteristics
4.2.1 General

Evaluation of detector characteristics for cardiac systems are performed extrinsically (with

COLLIMATORS in place). Additionally, for systems that allow the removal of the COLLIMATOR,

intrinsic detector characteristics shall be specified and tested in accordance with IEC 61675-2.

4.2.2 Energy resolution and LOW-ENERGY-TAIL RATIO measurement
4.2.2.1 General

Energy resolution describes the ability of the detector to properly identify the energy of the

detected photons. Due to incomplete charge collection, the detector material in some cardiac

systems may have an increased fraction of photons detected with reduced energy. The effect

is characterized by measuring the LOW-ENERGY-TAIL RATIO.
An energy spectrum is determined for each CARDIAC DETECTOR HEAD.
4.2.2.2 Purpose

The energy resolution is measured to characterize the ability of a GAMMA CAMERA to separate

photons with different energies.
4.2.2.3 Method

Measure an energy spectrum in low scatter configuration using an irradiation of the entire

CARDIAC DETECTOR HEAD. This measurement is performed separately for each CARDIAC DETECTOR

HEAD.
4.2.2.4 RADIONUCLIDE
99m 57
The sources are Tc and Co.
4.2.2.5 RADIOACTIVE SOURCE DISTRIBUTION

A LINE SOURCE with internal diameter of < 1,2 mm is placed so as to illuminate the entire CARDIAC

DETECTOR HEAD. The COUNT RATE shall not exceed 40 000 counts per second.
4.2.2.6 Data collection

For each CARDIAC DETECTOR HEAD, the pulse height spectrum is obtained with a channel width

less than or equal to 5 % of the expected photopeak FWHM. The number of counts in the peak

channel is greater than 10 000. The spectrum is obtained over the entire usable energy range

of the detector.
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4.2.2.7 Data processing

For the energy spectrum, the channel numbers are expressed in terms of energy by scaling the

channel number by the difference in peak energies of the two RADIONUCLIDES divided by the

difference in their measured peak channel positions.
4.2.2.8 Data analysis

For each CARDIAC DETECTOR HEAD, the energy resolution, E , is the FWHM of the full energy

FWHM

absorption peak with a peak energy, E , closest to the expected photopeak energy.

peak
For each CARDIAC DETECTOR HEAD, the LOW-ENERGY-TAIL RATIO, Q , is defined as:
tail
Q = Z / Z (1)
tail tail peak
where
Z is the sum of counts from the averaged energy spectrum in the ENERGY WINDOW
peak
centred on the energy peak E with the width of 2 × E ;
peak FWHM
Z is the sum of counts from the averaged energy spectrum in the ENERGY WINDOW
tail
centred on the energy E – 2 × E with the width of 2 × E .
peak FWHM FWHM
4.2.2.9 Report

The energy resolution, expressed as a percentage of the peak energy, and the LOW-ENERGY-

TAIL RATIO are reported for each CARDIAC DETECTOR HEAD. The mean and standard deviation of

the energy resolution and LOW-ENERGY-TAIL RATIO for the entire system is also reported if the

system has more than 5 CARDIAC DETECTOR HEADS.
4.2.3 Shield leakage
4.2.3.1 General

The DETECTOR SHIELD prevents the detection of unwanted photons originated from outside the

entrance field of view of the COLLIMATOR.
4.2.3.2 Purpose

The purpose of this test is to identify the locations of the highest leakage and its magnitude.

4.2.3.3 Method

The complete surface of cardiac camera system is swept with a collimated source searching for

the maximum leakage COUNT RATES at the rear and the side of the DETECTOR SHIELD and the

joints (particularly the joint between the COLLIMATOR And the DETECTOR SHIELD), if it is

accessible.
4.2.3.4 RADIONUCLIDE
99m
The source is Tc.
4.2.3.5 RADIOACTIVE SOURCE DISTRIBUTION

A small collimated source, as illustrated in Figure 1, with d not larger than 20 mm and t not less

than 10 mm, totally filled with the RADIONUCLIDE
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4.2.3.6 Data collection

The source is placed in contact with the external surface of the DETECTOR SHIELD and the joints

if accessible. The entire surface of the DETECTOR SHIELD is swept and the system COUNT RATES

measured during a clinical acquisition mode. For systems with a rotating gantry, the data

collection is performed at a single gantry angle.
4.2.3.7 Data processing

The maximum leakage COUNT RATES at the rear and the side of the DETECTOR SHIELD, normalized

to the source ACTIVITY, are recorded. Also the maximum leakage COUNT RATE at joints in the

shield, normalized to the source ACTIVITY, is recorded.
4.2.3.8 Data analysis

The normalized leakage COUNT RATES are divided by the sensitivity of the system as measured

in 4.2.5.
4.2.3.9 Report

The three normalized maximum leakage COUNT RATES expressed as a percentage of the

sensitivity measured in 4.2.5, and the locations at which they were measured, are reported.

Dimensions in millimetres
Figure 1 – Small shielded liquid source
NOTE See 4.2.3.5 for recommended values for d and t.
4.2.4 COUNT RATE performance
4.2.4.1 General

COUNT RATE performance depends in a complex manner on the spatial distribution of ACTIVITY

and scattering materials, which therefore should simulate clinical imaging situations. Therefore

the tests are conducted with COLLIMATOR and scattering material.
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COUNT RATE performance measures the relationship between the registered COUNT RATE and

ACTIVITY, i.e. the COUNT RATE CHARACTERISTIC. The COUNT RATE CHARACTERISTIC describes the

constancy of the GAMMA CAMERA sensitivity at different ACTIVITY levels and is highly dependent

on the set-up of the measurement conditions.
4.2.4.2 Purpose

The procedure described here is designed to evaluate deviations from the linear relationship

between COUNT RATE and ACTIVITY, caused by COUNT LOSSES, over a clinically relevant range of

COUNT RATES.
4.2.4.3 Method

Measurements of the COUNT RATE are performed at various ACTIVITY levels. The variation of

ACTIVITY is normally achieved by RADIOACTIVE decay. No correction is made for COUNT LOSSES

and scatter. Each measured count is taken into account only once.
4.2.4.4 RADIONUCLIDE
99m
The RADIONUCLIDE for the measurement is Tc with ENERGY WINDOW Of 140 keV ± 10 %.
4.2.4.5 RADIOACTIVE SOURCE distribution

A cylindrical phantom (Figure 2) with a LINE SOURCE insert is used. The phantom is filled with

non-radioactive water as a scatter medium. The LINE SOURCE of at least 7 cm in length is

inserted and positioned on the central axis of the cylinder. The LINE SOURCE is centred on the

REFERENCE POINT of the system and aligned with the patient inferior-superior axis.

Dimensions in millimetres
Figure 2 – Transverse slice of phantom used for measuring COUNT RATE performance
4.2.4.6 Data collection

A COUNT RATE CHARACTERISTIC (measured COUNT RATE versus incident COUNT RATE or ACTIVITY)

is to be measured by acquiring a series of images over time (e.g. frames). The variation of

ACTIVITY is accomplished by RADIOACTIVE decay with measurements continuing over

approximately 10 RADIOACTIVE HALF-LIVES. The time per frame is less than one-half of the

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RADIOACTIVE HALF-LIFE with the exception of the last three frames, which can be longer. The

initial amount of ACTIVITY is chosen to be 2 GBq ± 10 %.
A background acquisition is performed.
4.2.4.7 Data processing

The total counts acquired in each image is processed. Background correction is performed for

all frames.

The average of the decaying ACTIVITY, A , during the data acquisition interval for time frame i,

ave,i
T , is determined by the following equation:
acq,i
T
T −T  
1 T
cal 0,i acq,i
12/
exp ln2 1 exp ln2 (2)
AA −−
 
ave,i cal 
 
ln2 TT T
acq,i 1/ 2 1/ 2
 
where
A is the ACTIVITY Measured at time T ;
cal cal
T is the acquisition start-time of the time frame i;
0,i
T is the RADIOACTIVE HALF-LIFE of the RADIONUCLIDE in use.
1/2

From the above measurements, plot the COUNT RATE CHARACTERISTIC (i.e. measured COUNT RATE

versus ACTIVITY).
The conversion factor
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Questions, Comments and Discussion

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