Progress in Medical Radiation Physics

266 Pages·1985·8.201 MB·English

by  W. A. Jennings (auth.), Colin G. Orton (eds.)

Progress in
Medical Radiation
Physics
Volume 2
Progress In Medical Radiation Physics
Series Editor:
COLIN G. ORTON, Ph.D.
Department of Radiation Oncology
Wayne State University School of Medicine
Harper-Grace Hospitals
Detroit, Michigan
Editorial Board:
PETER R. ALMOND, Ph.D.
Department of Physics
M.D. Anderson Hospital
Houston, Texas
JOHN S. CLIFTON, M.Sc.
Department of Medical Physics
University College Hospital
London, England
J. F. FOWLER, Ph.D.
Director, Gray Laboratory
Mount Vernon Hospital
Northwood, Middlesex, England
JAMES G. KEREIAKES, Ph.D.
Eugene L. Saenger Radioisotope Laboratory
Cincinnati General Hospital
Cincinnati, Ohio
JACK S. KROHMER, Ph.D.
Department of Radiology
Wayne State University School of Medicine
Detroit, Michigan
CHRISTOPHER H. MARSHALL, Ph.D.
N.Y.U. Medical Center
New York, New York
Progress in
Medical Radiation
Physics
Volume 2
Edited by
COLIN G. ORTON
Wayne State University School of Medicine,
Harper-Grace Hospitals
Detroit, Michigan
PLENUM PRESS • NEW YORK AND LONDON
ISBN-13: 978-1-4612-9458-0 e-ISBN-13: 978-1-4613-2387-7
DOT: 10.1007/978-1-4613-2387-7
© 1985 Plenum Press, New York
Softcover reprint of the hardcover 1s t edition 1985
A Division of Plenum Publishing Corporation
233 Spring Street, New York, N.Y. 10013
All rights reserved
No part of this book may be reproduced, stored in a retrieval system, or transmitted,
in any form or by any means, electronic, mechanical, photocopying, microfilming,
recording, or otherwise, without written permission from the Publisher
Roy E. Ellis
This book is dedicated to the memory of our dear friend and colleague
Professor Roy E. Ellis, who, until his untimely death, was an active member
of our Editorial Board.
Throughout his career, Professor Ellis devoted himself tirelessly to the
safe use of radiation for the welfare of mankind. He was a very practical
man. He realized that radiation, used constructively, could be of considerable
benefit, yet, if applied indiscriminately, was a hazard which needed to be
controlled. He was a great leader both in the clinical application of radiation
and in protection against its harmful effects. Those of us who had the
pleasure of working with him will always relish the experience. It was an
honor and a privilege to have had Roy Ellis as a member of our Editorial
Board. His enthusiasm and vitality will be sorely missed.
Colin G. Orton
Contributors
J. A. Brace, Radiotherapy Department, Royal Free Hospital, London,
England
Lewis Burkinshaw, Department of Medical Physics, University of Leeds, The
General Infirmary, Leeds, England
T. J. Davy, Medical Physics Department, Royal Free Hospital, Hampstead,
London, England
Kunio Doi, Kurt Rossmann Laboratories for Radiologic Image Research,
Department of Radiology, University of Chicago, Chicago, Illinois
Paul A. Feller, Department of Radiology, The Jewish Hospital, Cincinnati,
Ohio
W. A. Jennings, National Physical Laboratory, Teddington, England
James G. Kereiakes, Department of Radiology, University of Cincinnati
College of Medicine, Cincinnati, Ohio
Stephen R. Thomas, Department of Radiology, University of Cincinnati
College of Medicine, Cincinnati, Ohio
vii
Preface
The Progress in Medical Radiation Physics series presents in-depth reviews of
many of the significant developments resulting from the application of
physics to medicine. This series is intended to span the gap between research
papers published in scientific journals, which tend to lack details, and
complete textbooks or theses, which are usually far more detailed than
necessary to provide a working knowledge of the subject.
Each chapter in this series is designed to provide just enough information
to enable readers to both fully understand the development described and
apply the technique or concept, if they so desire. Thorough references are
provided for those who wish to consider the original literature. In this way, it
is hoped that the Progress in Medical Radiation Physics series will be a
catalyst encouraging medical physicists to apply new techniques and
developments in their daily practice.
Colin G. Orton
ix
Contents
1-1. The Tracking Cobalt Project: From Moving-Beam
Therapy to Three-Dimensional Programmed Irradiation
W. A. Jennings
1. Introduction
2. Establishing Moving-Beam Techniques at the Royal Northern Hospital,
1945-1955 4
2.1. Alternative Moving-Beam Techniques 4
2.2. Conical-Rotation Therapy 5
2.3. Rotating-Chair Therapy 6
2.4. Arc or Pendulum Therapy 7
2.5. Relative Percentage Depth Doses Achieved 9
3. The Tracking Concept and the Operation of the Mark I Tracking Machine,
1957-1959 10
3.1. The Spread of Malignant Disease . 10
3.2. Realization of the Tracking Principle. 11
3.3. Achieving Uniform Dosage along the Track 14
3.4. Practical Application of the Tracking Technique. 15
4. Steps Toward an Improved Tracking Machine, 1960-1965 17
4.1. The Need for Penetrating Radiation . 17
4.2. Developing an Improved Control System 18
4.3. An Appeal for Funds for the Tracking Cobalt Project. 19
4.4. Consultations and Study Tour . 20
4.5. The Need for Elliptical Dose Contours . 22
5. Dosimetry and Treatment Planning for the Mark II Tracking Machine. 23
5.1. Achieving Elliptical Dose Contours-the Approach Adopted 23
5.2. Sectional Dose Computations 24
5.3. Sectional and Track Dose Measurements 25
5.4. Track Dosage . 25
6. Alternative Approaches to Conformation Therapy under Parallel
Development Elsewhere-Synchronous Beam-Shaping and Shielding 26
xi
xii Contents
7. Constructing and Installing the Mark II Tracking Machine, 1965-1970 27
8. Commissioning and Using the Mark II Tracking Machine, 1970-1975 30
8.1. The Tracking Cobalt Unit . . . . 30
8.2. Commissioning the TCU ............. 31
8.3. Examples of Treatment Applications . . . . . . . .. 33
9. Developing and Commissioning the Mark III Tracking Cobalt Machine,
1975-1980 . . . . . . . . . . . . . . 35
9.1. Limitations of the Mark II Machine. . . 35
9.2. Developing the Mark III Tracking Machine 36
9.3. Treatment Planning by Computer. . . . 36
9.4. Funding, Constructing, Installing, and Commissioning the CCTCU. 37
9.5. Clinical Indications of Conformation Therapy . . . . . 37
9.6. Examples of Dose Distributions Achieved with the CCTCU 38
9.7. Recent Developments . . . . . . . . . . . . . 39
10. Alternative Approaches to Computer-Controlled Radiotherapy 41
References. . . . . . . . . . . . . . . . . . . . . 42
1-11. Physical Aspects of Conformation Therapy Using Computer
Controlled Tracking Units
T. J. Davy
1. Introduction 45
2. Methods for Achieving Conformation Therapy Using Photon Beams 47
2.1. Basic Requirements for Controlling Dose Distributions in Three
Dimensions. 47
2.2. A Brief Comparison of Conformation Therapy Systems 48
3. Representing Three-Dimensional Treatment Parameters . 50
3.1. The "Ideal" Beam 50
3.2. Exposure-Time Profiles, Exposure-Dose Profiles, and Absorbed-Dose
Profiles 52
3.3. Radial Time and Exposure-Weighting Diagrams. 56
3.4. Combining Axial Exposure-Time Profiles 58
3.5. Combining Tracks Using Exposure-Time Profiles 60
3.6. Combining Axial Exposure-Time Profiles and Transverse-Plane
Exposure-Time Profiles 60
4. Controlling Radiotherapy Dose Distributions in Three Dimensions Using
a Computer-Controlled Tracking Unit 63
4.1. Slice-by-Slice or Field-by-Field Treatment and Planning. 63
4.2. Controlling the Shape of the High-Dose Volume 64
4.3. Controlling the Dose Distribution along the Tumor Axis. 67
4.4. The End-of-Track Technique 68
5. A Note on Treatment-Planning Strategy 70
5.1. Thin-Slice and Thick -Slice Planning . 70
5.2. Slice-by-Slice Treatment Planning. 72
5.3. Field-by-Field Treatment Planning 72