Overview of Geant 4 applications in Medical Physics

Overview of Geant 4 applications in Medical Physics 2003 IEEE Nuclear Science Symposium And Medical Imaging Conference Tuesday, 21 st October, 2003 Portland, Oregon, USA Susanna Guatelli INFN, Genova, Italy 1

Monte. Carlo Methods in radiotherapy Monte. Carlo methods have been explored for years as a tool for precise dosimetry, in alternative to analytical methods De facto, Monte. Carlo simulation is not used in clinical practice (only side studies) The limiting factor is the speed Challenge : develop MC for clinical use ØReliable? Other limitations: ØFor “software specialists only”, not user-friendly for general practice 2

Extensibility to accommodate new user requirements (thanks to the OO technology) Specific facilities controlled by a friendly UI A rigorous software process The transparency of physics Use of evaluated data libraries Adoption of standards wherever available (de jure or de facto) Independent validation by a large user community worldwide User support from experts 3

Geant 4 is an Object Oriented Toolkit for the simulation of the passage of particles through matter. Its application areas include high energy and nuclear physics experiments, astrophysics, medical physics, physics radiation background studies, radioprotection and space science Geant 4 exploits advanced Software Engineering techniques and Object Oriented technology Geant 4 has been developed and maintained by a world-wide collaboration of more than 100 scientists The source code and libraries are freely distributed from the Geant 4 web site Katsuya Amako: Geant 4 Simulation Toolkit: Overview and Its Object. Oriented Design , 22 October, 8. 15 useful links: www. cern. ch/geant 4 www. ge. infn. it/geant 4 4

Geant 4 applications in Medical Physics Verification of conventional radiotherapy treatment planning (as required by protocols) Investigation of innovative methods of radiotherapy Radiodiagnostic Dosimetric studies at cellular level 5

Geometry Detailed set-up description and efficient navigation CSG (Constructed Solid Geometries) Ø simple solids BREPS (Boundary REPresented Solids) Ø volumes defined by boundary surfaces Ø polyhedra, cylinders, cones, toroids etc. Boolean solids Øunion, subtraction… Proton line beam Fields: variable nonuniformity and differentiability ATLAS 6

Geant 4 -Dicom interface Modelisation of complex structures file Reproduce patient’s anatomy in a Geant 4 application Developed by L. Archambault, L. Beaulieu, V. -H. Tremblay (Univ. Laval and l'Hôtel-Dieu, Québec) 7

Modelisation of beam lines Head Radiotherapy High energy electron beam, 50 Me. V Karolinska Institutet, Stockholm Susanne Larsson Roger Svensson Irena Gudowska Björn Andreasen Modelisation of electromagnetic field Intra. Operative Radiation Therapy(IORT) Electron beam IORT Novac 7 G. Barca*, F. Castrovillari**, D. Cucè**, E. Lamanna**, M. Veltri* * Azienda Ospedaliera (Hospital) of Cosenza **Physics Dep. , UNICAL & INFN, Cosenza 8

GATE Collaboration Geant 4 application for tomographic emission (GATE) is a recently developed simulation platform based on Geant 4, specifically designed for PET and SPECT studies. Talk: Steven Staelens, Overview of GATE, Experimental set-up changing with time PEM Positron Emission Mammography (PEM) Talk: A. Trindade Geant 4 Applications and Developments for Medical Physics Experiments 9

Electromagnetic physics Multiple scattering Bremsstrahlung Ionisation Annihilation Photoelectric effect Compton scattering Rayleigh effect g conversion e+e- pair production Synchrotron radiation Transition radiation Cherenkov Refraction Reflection Absorption Scintillation Fluorescence Auger electrons and positrons gamma, X-ray and optical photons muons charged hadrons ions High energy extensions needed for LHC experiments, cosmic ray experiments… Low. Energy extensions fundamental for medical applications Alternative models for the same process Data driven, Parameterised and Hadronic – the most complete hadronic simulation kit on theoretical models market – alternative and complementary models physics 10

Geant 4 dosimetric validations Dosimetric validations Validation is fundamental for Medical Physics Applications The validation process includes different levels Microscopic validation: physics models validation Macroscopic validation: experimental set-up validation Validation in respect to experimental measurements Macroscopic validation Microscopic validation See S. Guatelli, Precision Validation of Geant 4 Electromagnetic Physics (22 October) See G. Folger, Validation of Geant 4 Hadronic Physics (22 October) Talk J. F Carrier: Validation of GEANT 4 for Simulations in Medical Physics 11

Brachytherapy Low Energy Physics for accurate dosimetry Dosimetry for all brachytherapic devices Collaboration of frameworks Analysis, UI, Visualisation, Access to distributed resources Talk: S. Guatelli From DICOM to GRID: a dosimetric system for brachytherapy born from HEP 12

Hadrontherapy Hadron therapy Electromagnetic and hadronic interactions for protons, ions(and secondary particles) Proton beam line Talk: P. Cirrone Implementation of a New Monte Carlo Simulation Tool for the Development of a Proton Therapy Beam Line and Verification of the Related Dose Distributions 13

Metabolic Therapy with 131 I ] Isotope accumulated in the damaged lobe can destroy pathological cells without any surgical operation 131 I 131 Xe + - + Radioactive Decay Module 131 I 131 Xe (excited) 131 Xe (stable) G. Barca*, F. Castrovillari**, D. Cucè**, E. Lamanna**, M. Veltri* * Azienda Ospedaliera (Hospital) of Cosenza **Physics Dep. , UNICAL & INFN, Cosenza 14

Shielding and radioprotection in space missions Collaboration ESA, ALENIA SPAZIO, INFN Genova in AURORA project G. Brambati 1, V. Guarnieri 1, S. Guatelli 2, C. Geant 4 application not only Lobascio 1, P. Parodi 1, M. G. Pia 2 1. ALENIA SPAZIO, Torino, Italy, 2. INFN Genova, Italy in hospital treatments AURORA explore the solar system and the Universe ØGeant 4 application for shielding and astronauts’ radioprotection studies 15

Geant 4 -DNA Simulation of Interactions of Radiation with Biological Systems at the Cellular and DNA Level Geant 4 applications in chemistry and biochemistry 16

Dosimetry at cellular level Light-ion microbeams provide a unique opportunity to irradiate biological samples at the cellular level and to investigate radiobiological effects Accurate description at cellular level Talk S. Incerti: Simulation of cellular irradiation with the CENBG microbeam line using GEANT 4 17

How to achieve quick response? 18

Network network of Personal Computer as a realistic alternative to a high-costs dedicated parallel hardware to be used in clinical practice Talk S. Schauvie: Radiotherapy treatment planning with Monte Carlo on a distributed system S. Chauvie 1, 2, G. Scielzo 1 1 Ordine Mauriziano - IRCC 2 INFN 19

Parallel mode: distributed resources Distributed Geant 4 Simulation talk: DIANE -- Distributed Analysis Environment for GRID-enabled Simulation and Analysis of Physics Data (Friday 24 th October) 20

Conclusions Geant 4 is a powerful and reliable tool for medical physics studies adoption of rigorous software process Transparency of the physics Alternative and complementary physics models Accurate description of experimental set-up Many applications in Medical Physics and Medical Imaging Valid example of technology transfer Integration to the GRID offers quick response 21