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Atoms for Peace Atoms for Peace Atoms for Peace Atoms for Peace Atoms for Peace P1514_vol2_cover.indd 1 2011-12-07 09:18:31 Atoms for Peace Atoms for Peace P1514_vol2_cover.indd 2 2011-12-07 09:18:39 STANDARDS, APPLICATIONS AND QUALITY ASSURANCE IN MEDICAL RADIATION DOSIMETRY (IDOS) VOLUME 2 The Agency’s Statute was approved on 23 October 1956 by the Conference on the Statute of the IAEA held at United Nations Headquarters, New York; it entered into force on 29 July 1957. The Headquarters of the Agency are situated in Vienna. Its principal objective is “to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world’’. PROCEEDINGS SERIES STANDARDS, APPLICATIONS AND QUALITY ASSURANCE IN MEDICAL RADIATION DOSIMETRY (IDOS) PROCEEDINGS OF AN INTERNATIONAL SYMPOSIUM ON STANDARDS, APPLICATIONS AND QUALITY ASSURANCE IN MEDICAL RADIATION DOSIMETRY (IDOS) ORGANIZED BY THE INTERNATIONAL ATOMIC ENERGY AGENCY IN COOPERATION WITH THE AMERICAN ASSOCIATION OF PHYSICISTS IN MEDICINE, ASIA–OCEANIA FEDERATION OF ORGANIZATIONS FOR MEDICAL PHYSICS, ASOCIACIÓN LATINOAMERICANA DE FÍSICA MÉDICA, BUREAU INTERNATIONAL DES POIDS ET MESURES, EUROPEAN COMMISSION, EUROPEAN FEDERATION OF ORGANISATIONS FOR MEDICAL PHYSICS, EUROPEAN SOCIETY FOR THERAPEUTIC RADIOLOGY AND ONCOLOGY, INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION, INTERNATIONAL COMMISSION ON RADIATION UNITS AND MEASUREMENTS, INTERNATIONAL ORGANIZATION FOR MEDICAL PHYSICS, INSTITUTE OF PHYSICS AND ENGINEERING IN MEDICINE, SOCIETY OF NUCLEAR MEDICINE, UNITED NATIONS SCIENTIFIC COMMITTEE ON THE EFFECTS OF ATOMIC RADIATION, WORLD FEDERATION OF NUCLEAR MEDICINE AND BIOLOGY AND THE WORLD HEALTH ORGANIZATION AND HELD IN VIENNA, 9–12 NOVEMBER 2010 In two volumes VOLUME 2 INTERNATIONAL ATOMIC ENERGY AGENCY VIENNA, 2011 COPYRIGHT NOTICE All IAEA scientific and technical publications are protected by the terms of the Universal Copyright Convention as adopted in 1952 (Berne) and as revised in 1972 (Paris). The copyright has since been extended by the World Intellectual Property Organization (Geneva) to include electronic and virtual intellectual property. Permission to use whole or parts of texts contained in IAEA publications in printed or electronic form must be obtained and is usually subject to royalty agreements. Proposals for non-commercial reproductions and translations are welcomed and considered on a case-by-case basis. Enquiries should be addressed to the IAEA Publishing Section at: Marketing and Sales Unit, Publishing Section International Atomic Energy Agency Vienna International Centre PO Box 100 1400 Vienna, Austria fax: +43 1 2600 29302 tel.: +43 1 2600 22417 email: [email protected] http://www.iaea.org/books © IAEA, 2011 Printed by the IAEA in Austria November 2011 STI/PUB/1514 IAEA Library Cataloguing in Publication Data International Symposium on Standards, Applications and Quality Assurance in Medical Radiation Dosimetry (2010 : Vienna, Austria) Standards, applications and quality assurance in medical radiation dosimetry (IDOS) : proceedings of an international symposium, Vienna, 9–12 November 2010. — Vienna : International Atomic Energy Agency, 2011. 2 v. ; 24 cm. — (Proceedings series, ISSN 0074–1884) STI/PUB/1514 ISBN 978–92–0–116210–6 Includes bibliographical references. 1. Radiation dosimetry — Congresses. 2. Radiation dosimetry — Standards. 3. Diagnostic imaging — Safety measures. 4. Radiation protection. I. International Atomic Energy Agency. II. Series: Proceedings series (International Atomic Energy Agency). IAEAL 11–00712 FOREWORD Ionizing radiation is employed in a wide variety of applications and processes in technologically advanced countries. Dosimetry is the science of measuring ionizing radiation and understanding it is essential for the safe and effective use of nuclear technology. Medical radiation dosimetry deals with those applications in which patients are irradiated. These proceedings embody a selection of refereed papers that were presented at the International Symposium on Standards, Applications and Quality Assurance in Medical Radiation Dosimetry held in Vienna from 9 to 12 November 2010. More than 370 delegates representing 66 Member States, 45 observers and 12 international and professional organizations attended the meeting, at which 75 oral presentations were delivered, 4 round table discussions were held and 187 posters were presented. Owing to its dual role in disseminating radiation measurement standards and verifying the accuracy of dosimetry applied at the hospital level, the IAEA is well positioned to convene international meetings focused on dosimetry. The previous meeting was held in Vienna in November 2002. Since then, three major developments have helped progress medical radiation dosimetry. Firstly, Member States have rapidly adopted new treatment technologies, e.g. intensity modulated radiotherapy (IMRT), and they have continued to acquire sophisticated diagnostic capabilities, e.g. computed tomography (CT) and positron emission tomography scanning. Unfortunately, the adoption of these technologies has not always been trouble-free. News stories in various countries have highlighted radiation accidents during IMRT due to dosimetric errors. In addition, overuse of CT scanning and failure to adopt clinical protocols appropriate to patient size, particularly in paediatric cases, have caused concern. Measurement of radiation dose properly necessitates adoption of new technologies and, consequently, much research has been devoted to improving dosimetry, particularly for the small fields typically used in IMRT. Secondly, dosimetry protocols based on standards of absorbed dose to water, which simplified the translation of basic dosimetry from the standards laboratory to the hospital level, are 10 years old and need reviewing. There have been advances in dosimetry for both graphite and water calorimetry for external beam therapy and the strengthening of dosimetry for beams of protons and light ions, as their use is implemented clinically. Advances have also been made at primary laboratories to develop absorbed dose to water standards for brachytherapy sources that are inserted directly into patients. All these issues were addressed during the symposium. Thirdly, there has been a rapid expansion in the level of diagnostic information for therapy planning, delivery and patient follow-up. New paradigms have been created for more comprehensive quality assurance. Since auditing physical dosimetry is an integral part of quality auditing for the whole process of treating patients, one session focused on it. The ongoing need to optimize radiation doses justified a session on radiation protection dosimetry. In addition to oral and poster presentations, four interactive, round table discussions were held, focusing on the consequences of dosimetry errors, dosimetry knowledge gaps for new technologies, the role of education and training to improve dosimetric understanding and the meaning of traceability in the dosimetric chain. A CD-ROM of the contributed papers accompanies these proceedings. The IAEA gratefully acknowledges the contributions made by the Programme Committee, the collaborating organizations, and the session chairs, co-chairs and scientific reviewers. EDITORIAL NOTE The papers in these Proceedings (including the figures, tables and references) have undergone only the minimum copy editing considered necessary for the reader’s assistance. The views expressed remain, however, the responsibility of the named authors or participants. In addition, the views are not necessarily those of the governments of the nominating Member States or of the nominating organizations. Although great care has been taken to maintain the accuracy of information contained in this publication, neither the IAEA nor its Member States assume any responsibility for consequences which may arise from its use. The use of particular designations of countries or territories does not imply any judgement by the publisher, the IAEA, as to the legal status of such countries or territories, of their authorities and institutions or of the delimitation of their boundaries. The mention of names of specific companies or products (whether or not indicated as registered) does not imply any intention to infringe proprietary rights, nor should it be construed as an endorsement or recommendation on the part of the IAEA. The authors are responsible for having obtained the necessary permission for the IAEA to reproduce, translate or use material from sources already protected by copyrights. This publication has been prepared from the original material as submitted by the authors. The views expressed do not necessarily reflect those of the IAEA, the governments of the nominating Member States or the nominating organizations. The IAEA has no responsibility for the persistence or accuracy of URLs for external or third party Internet web sites referred to in this book and does not guarantee that any content on such web sites is, or will remain, accurate or appropriate. CONTENTS OF VOLUME 2 CLINICAL DOSIMETRY IN X RAY IMAGING (Session 4) Calibration of kerma area product meters with a patient dose calibrator . 3 P. Toroi, M. Husso, A. Kosunen Calibration of pencil type ionization chambers at various irradiation lengths and beam qualities. 21 C.J. Hourdakis, A. Boziari, E. Koumpouli Performance test of multi-parameter measuring devices used for quality assurance in diagnostic radiology . 33 L. Büermann, R. Böttcher Reference X ray field for mammography
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