Particle Therapy Technology for Safe Treatment 1st Edition by Jay Flanz ISBN 9781000528060 1000528065

Chapter 1 Introduction

Chapter 2 Evolution of Medical Particles

Chapter 3 A Personal Historical Perspective

Chapter 4 Flow of Requirements

4.1 Direct Requirements

4.2 Developmental Requirements

Chapter 5 External Beam Systems

Chapter 6 How to Damage Unwanted Cells

6.1 Direct Effects

6.2 Indirect Effects

Chapter 7 Exponentials

7.1 e

7.2 Distributions

7.2.1 Binomial Distribution

7.2.2 Poisson Distribution

7.2.3 Gaussian Distribution

7.2.3.1 Mean

7.2.3.2 Standard Deviation

7.2.3.3 Skewness and Kurtosis

7.2.3.4 Gaussian Algebra

7.2.3.5 Summation of Gaussians

7.3 Interactions

7.3.1 Can Hit the Broad Side of a Barn

7.3.2 Interaction Target

7.3.3 Target Hits

7.3.4 Why Radiotherapy Works Mathematically

7.3.4.1 Tolerances

7.3.5 Attenuation

7.4 Exercises

Chapter 8 Relativistic Dynamics

8.1 Special Relativity (Briefly in this Time Frame)

8.2 Dynamics

8.3 Exercises

Chapter 9 Charged Particle Interactions in Matter

9.1 Energy Loss

9.2 Ionization Potential

9.3 Linear Thickness or Mass Thickness

9.4 Range

9.4.1 Range Sensitivity

9.4.2 Energy Loss, Distal Dose Falloff or Range Spread

9.5 Scattering

9.6 Dependence of the Bragg Peak on the Beam Size

9.7 Energy Loss and Scattering Dependencies

9.8 What Could Go Wrong – 1?

9.9 Exercises

Chapter 10 Review of Charged Particle Motion

10.1 Manipulation of Light Rays

10.2 Electromagnetic Forces

10.3 Equations of Motion

10.3.1 Bending in a Magnetic Field

10.3.2 The Form of the Force

10.3.3 The Equations of Motion in a Magnetic Field

10.4 Effects of Beam Transport Elements

10.4.1 Drift Space

10.4.2 Thin Lens Focusing Elements

10.5 General Ray Coordinate Transformation

10.6 Optical Matrix Examples

10.6.1 Momentum

10.6.2 Longitudinal Position

10.6.3 Transverse Focusing

10.6.3.1 Point-to-Point Focusing

10.6.3.2 Point-to-Parallel Focusing

10.6.3.3 Parallel-to-Point Focusing

10.6.3.4 Achromatic Combined System.

10.6.4 Variables and Conditions

10.7 The Orthogonal Direction

10.8 Dipole Focusing

10.8.1 Sector Focusing

10.8.2 Pole Edge Focusing

10.9 Misalignments

10.10 What Could Go Wrong – 2?

10.11 A Beam; A Gaussian Beam

10.11.1 The Ellipse

10.11.2 Phase Space Representation and Equation of the Beam

10.12 Propagation of the Beam

10.12.1 Propagation of a Beam in a Drift Length

10.12.2 Representation of Apertures

10.12.3 Dispersion

10.12.4 The Effect of Multiple Scattering

10.13 Beam Matching Beamlines

10.14 What Could Go Wrong – 3?

10.15 Exercises

Chapter 11 Clinical Perspective of Charged Particle Therapy Beams

11.1 Longitudinal Direction

11.1.1 Beam Range

11.1.2 Distal Penumbra

11.2 Transverse Direction

11.2.1 Field Size

11.2.2 Lateral Penumbra

11.3 Dose Conformance

11.3.1 Dose and Dose Rate

11.3.1.1 Dose

11.3.1.2 Counting Dose (Ionization Chamber)

11.3.1.3 Dose Quantities, Dose Rate and Irradiation Time

11.3.1.4 Maximum Count Rate

11.3.1.5 Dose Rate Considerations

11.3.2 Some Particle Beam Treatment-Related Considerations

11.3.3 Beam Directions

11.3.4 Additional Perspective

11.4 What Could Go Wrong – 4?

11.5 Exercises

Chapter 12 Three-Dimensional Dose Conformation

12.1 Longitudinal Beam Conformance

12.1.1 Degrading Methods

12.1.1.1 Ridge Filter

12.1.1.2 Range Modulator Wheel

12.1.1.3 Beam Current Modulation

12.1.1.4 Other Degrading Methods

12.1.2 Discrete Energy Changes

12.1.3 Range Compensation

12.2 Transverse Beam Conformance by Scattering

12.2.1 Single Scattering

12.2.2 Double Scattering

12.2.2.1 Beam Properties

12.2.2.2 Patient-Specific Hardware

12.2.2.3 Scattering System Components

12.3 Transverse Beam Conformance by Scanning

12.3.1 Scanning Methods

12.3.2 General Description of Scanning

12.3.3 Technical Scanning Delivery Techniques

12.3.3.1 Time- or Dose-Driven

12.3.3.2 Variation of Speed and/or Current

12.3.3.3 Dimensional Priority

12.3.4 Clinical Delivery Styles

12.3.4.1 Uniform Scanning

12.3.4.2 Single Field Uniform Dose

12.3.4.3 Multi Field Delivery

12.3.4.4 Distal Edge Tracking

12.3.5 Beam Motion (Not Patient Motion) Effects

12.3.6 Scanning Irradiation Time

12.3.7 Time Sensitivities to Scanning Hardware

12.3.7.1 Time vs. Dose

12.3.7.2 Time vs. Current

12.3.7.3 Time vs. Range

12.3.7.4 Time vs. SAD

12.3.7.5 Time vs. Magnet Current Ramp Rate

12.3.7.6 Time vs. Beam Off Time

12.3.7.7 Time vs. Energy Change Time

12.3.7.8 Other Considerations

12.3.8 Dose Rate Tolerances

12.3.9 Pulsed Beams

12.3.10 Scanning Hardware

12.3.10.1 Scanning Dipoles

12.3.10.2 Dipole Contribution to Scanning Irradiation Time

12.3.11 Scanning Beam Parameters

12.3.11.1 Static Beam Parameters

12.3.11.2 Transverse Dose Distribution, Penumbra 
and Modulation

12.3.12 Sensitivities (Scanning)

12.3.13 Scan Patterns

12.3.14 The Effects of the Scanning Nozzle on the Beam Size

12.3.14.1 Chamber and Windows

12.3.14.2 Downstream Materials

12.3.14.3 Influence of the Dipole Exit Window 
on the Beam

12.3.14.4 Influence of the Large Vacuum Window 
on the Beam Width

12.3.14.5 Effect of the Air Gap on the Beam Width

12.3.14.6 Beam Widths with Air Gaps Inside Target

12.3.14.7 Effect of Range Shifter on Beam Width

12.3.15 Scanning Control and Requirement Considerations

12.3.15.1 More About Parameters

12.3.16 Faster Scanning Systems

12.3.17 Spreading Beams Summary

12.3.18 How to Build a Scanning System

12.4 What Could Go Wrong – 5?

12.4.1 Longitudinal Spreading

12.4.2 Transverse Spreading

12.5 Exercises

Chapter 13 Accelerator Systems

13.1 Accelerator Technology

13.2 Time Structure of Accelerator Beams

13.3 Cyclotron-Based Beam Production

13.3.1 Phase Slippage

13.3.2 Cyclotron Focusing Effects

13.3.3 Cyclotron Parameters

13.3.3.1 Energy

13.3.3.2 Beam Phase Space Area

13.3.3.3 Current

13.3.3.4 Time Dependence

13.3.3.5 Operability

13.3.3.6 Size

13.4 Degrader and Energy Selection System

13.4.1 Beam Conditions Resulting from a Degrader

13.4.2 Energy Selection System

13.4.3 Degrader to Beamline Collimator Conditions

13.4.4 Optics to Decouple Some Beamline Effects

13.4.5 Degrader and ESS Summary

13.5 Synchrotron-Based Systems

13.5.1 Synchrotron Timing

13.5.2 Equation of Motion (General Case)

13.5.2.1 Interpretation of the Parameters 
of the Equation of Motion

13.5.3 Relationship Between the Transfer Matrix 
and the Trajectory Equation

13.5.4 Stability of a Closed Machine Particle Trajectory

13.5.5 And We’re Out of Here

13.5.6 Synchrotron Beam Parameters

13.5.6.1 Energy

13.5.6.2 Beam Phase Space

13.5.6.3 Synchrotron Charges and Currents

13.5.6.4 Timing

13.5.6.5 Cost

13.5.7 Existing Synchrotron Systems

13.5.8 The Future of Synchrotrons

13.6 Accelerators

13.7 What Could Go Wrong – 6?

13.8 Exercises

Chapter 14 Gantries

14.1 Introduction

14.2 Accelerator on a Gantry

14.2.1 Cyclotron on a Gantry

14.2.2 Synchrotron on a Gantry

14.3 Gantry Geometry

14.3.1 Issues Affecting the Gantry Design Parameters

14.3.1.1 Physical Implications of Clinical Issues

14.3.1.2 Physical Implications of Magnetics

14.3.1.3 Desirable Features

14.3.1.4 Compact Gantry Parameters

14.4 Magnetic Spreading Geometry Considerations

14.5 Beam Optics Considerations

14.5.1 Beam Phase Space Conditions at the Gantry Coupling

14.5.2 Minimizing the Gantry Dispersion Function

14.5.2.1 Suppression of Dispersion

14.5.2.2 Momentum Bandwidth

14.5.2.3 Beam Profile for Beam Delivery

14.6 Gantry Examples

14.6.1 High-Level Gantry Requirements

14.6.2 The Corkscrew Gantry

14.6.3 In-Plane Gantry

14.6.4 Compact Gantries

14.7 Additional Gantry Considerations

14.7.1 The Cost of Beam Size

14.7.2 Room Size Matters

14.7.3 There Is No Isocenter

14.8 Gantry – Less or More?

14.9 What Could Go Wrong – 7?

14.10 Exercises

Chapter 15 Safety in Radiotherapy

15.1 Processes to Raise Safety Awareness

15.2 Introduction to Hazards and Mitigations

15.3 Introduction to Risks and Criticality

15.3.1 Hierarchy of Risk Parameters

15.4 Categories and Qualifiers of Risk

15.4.1 RPN, Risk and Categories

15.4.2 Brute Force Calculation

15.4.3 Binary Combination

15.5 Models and Methodologies

15.5.1 Dominos, Swiss Cheese, But No Wine

15.5.2 FRAM

15.5.3 STAMP

15.5.4 Tools and Methods

15.5.5 Practical Considerations

15.6 Hazard Analysis

15.6.1 Pick a Hazard, Any Hazard

15.6.2 Identify a Subsystem

15.6.3 Hazard Table

15.6.4 Radiotherapy Radiation Hazard 
and Risk Examples

15.7 Failure Mode and Effects Analysis (FMEA)

15.7.1 FMEA Example

15.7.2 FMEA Limitations

15.8 Mitigation of Risk

15.8.1 Training

15.8.2 Communication

15.8.3 Standard Operating Procedures

15.8.4 Equipment Design

15.9 Quality Assurance

15.9.1 Beam Quality Assurance

15.9.2 Clinical and Machine Parameters

15.9.3 Instrument QA

15.9.4 How Often to Measure

15.10 Quick Quality Assurance

15.11 Beyond Safety

15.12 What Could Go Wrong – 8?

15.13 Exercises

Chapter 16 Sensitivities and Tolerances: Scattering

16.1 Methodology

16.1.1 Input Beam Perturbations

16.1.2 Component Perturbations: Second Scatterer

16.1.3 Correction Capability

16.1.4 Ionization Chamber Perturbations

16.1.5 Range Modulator Perturbations

16.2 Discussion

Chapter 17 From Clinical to Technical Tolerances: Scanning

17.1 The Chicken or the Egg

17.2 The Acceptance Criteria

17.3 Gamma Index

17.4 Tolerances

17.4.1 Clinical Cases Used for the Study

17.4.2 Error Simulations

17.4.2.1 Accuracy vs. Reproducibility

17.4.2.2 Error Introduction

17.4.3 Evaluation of Tolerances

17.5 Flow to Technical Tolerances

17.5.1 Beam Range

17.5.2 Beam Size

17.5.3 Dose Weight

17.5.4 Beam Position

17.6 Exercises

Chapter 18 Afterword

Acknowledgments

Appendix A: Particle Therapy Facilities (as of June 2021)

Appendix B: Some Useful Constants

Appendix C: Hazard Topics

Appendix D: Beam QA Frequency Possibility

Appendix E: Some Element and Compound Parameters

Index