Experience in Medical Physics Stphane Chauvie Ospedale Santa

Experience in Medical Physics Stéphane Chauvie Ospedale Santa Croce e Carle, Cuneo and INFN Sezione di Torino Susanna Guatelli, Maria Grazia Pia INFN Sezione di Genova on behalf of the Geant 4 -INFN Group Sistemi di Calcolo Avanzato per la Pratica Clinica e la Ricerca in Fisica Medica Istituto Superiore di Sanità Roma, 13 December 2005 Maria Grazia Pia, INFN Genova

Object Oriented Toolkit for the simulation of particle interactions with matter also… An experiment of distributed software production and management An experiment of application of rigorous software engineering methodologies and object oriented technology to the particle physics environment Maria Grazia Pia, INFN Genova Born from the requirements of large scale HEP experiments Widely used not only in HEP • Space science and astrophysics • Medical physics, medical imaging • Radiation protection • Accelerator physics • Pest control, food irradiation • Landmining, security • etc. • Technology transfer R&D phase: RD 44, 1994 - 1998 1 st release: December 1998 2 new releases/year since then

in a nutshell Geant 4 architecture Rigorous software engineering – Interface to external products w/o dependenci es Domain decompositio n – – Geometry – – hierarchical structure of sub-domains Uni-directional flow of dependencies Iterative-incremental software process Object oriented methods Quality assurance – – Powerful and versatile geometry modelling Multiple solid representations handled through the same abstract interface (CSG, STEP compliant solids, BREPs) Simple placements, parameterised volumes, replicas, assembly-volumes etc. Boolean operations on solids Physics independent from tracking Subject to rigorous, quantitative validation Electromagnetic physics – Standard, Low-Energy, Muon, Optical etc. Hadronic physics – Parameterised, data-driven, theory-driven models Interactive capabilities – Maria Grazia Pia, INFN Genova – Visualisation, UI/GUI Multiple drivers to external systems

~100 members Geant 4 Collaboration Mo. U based Development, Distribution and User Support of Geant 4 Major physics laboratories: CERN, KEK, SLAC, TRIUMF, TJNL European Space Agency: ESA National Institutes: INFN, IN 2 P 3, PPARC Universities: Budker Inst. , Frankfurt, Karolinska Inst. , Helsinki, Lebedev Inst. , LIP, Lund, Northeastern etc. Maria Grazia Pia, INFN Genova

Medical applications PET, SPECT Courtesy of GATE Collaboration Courtesy of B. Mascialino et al. , INFN Genova Radiotherapy with external beams, IMRT Courtesy of P. Cirrone et al. , INFN LNS Radiation Protection Maria Grazia Pia, INFN Genova Courtesy of J. Perl, SLAC Hadrontherapy Brachytherapy Courtesy of S. Guatelli et al, . INFN Genova Courtesy of L. Beaulieu et al. , Laval

“Comparison of Geant 4 electromagnetic physics models against the NIST reference data” IEEE Transactions on Nuclear Science, vol. 52 (4), pp. 910 -918, 2005 Geant 4 electromagnetic physics models are accurate Compatible with NIST data within NIST accuracy (Low. E p-value > 0. 9) Mass attenuation coefficient in Fe Geant 4 Low. E Penelope Geant 4 Standard Geant 4 Low. E EPDL NIST - XCOM Results All Geant 4 models compatible with NIST Best agreement: Geant 4 Low. E models p-value stability study H 0 REJECTION AREA Maria Grazia Pia, INFN Genova

http: //www. ge. infn. it/geant 4/dna Maria Grazia Pia, INFN Genova

for medicine Macroscopic – – calculation of dose medical imaging already feasible with Geant 4 develop useful associated tools Complexity of software, physics and biology Cellular level – – cell modelling processes for cell survival, damage etc. DNA level – – – addressed with an iterative and incremental software process Parallel development at all the three levels (domain decomposition) DNA modelling physics processes at the e. V scale processes for DNA strand breaking, repair etc. Maria Grazia Pia, INFN Genova

Geant 4 in a distributed computing environment DIANE Transparent access to a distributed computing environment Parallelisation Access to the GRID Developed by J. Moscicki, CERN http: //cern. ch/DIANE prototype for an intermediate layer between applications and the GRID Maria Grazia Pia, INFN Genova Geant 4 applications running on a single computer, computer on a local farm, farm on the GRID Same code Master-Worker model

United Nations World Summit on Information Society Geneva, December 2003 Geant 4 – INFN presentation Maria Grazia Pia, INFN Genova

Monte Carlo for Medical Physics Medical physics does not only require fast simulation… Advanced functionality in geometry, physics, visualisation etc. A rigorous software process Specific facilities controlled by a friendly UI Extensibility to accommodate new user requirements Transparency of physics Quality Assurance What in HEP software is relevant to the bio-medical community? User support Adoption of standards from experts wherever available Maria Grazia Pia, INFN Genova based on sound software engineering Independent validation by a large user community worldwide Use of evaluated data libraries

Meditations… Software for medical physics – – R&D vs usage in a clinical environment requirements engineering Technological background – – – what is the technological education in Medical Physics Schools in Italy? how do medical physicists keep up-to-date in a fast evolving computing environment? software technology course in Medical Physics School in Genova suppressed after 1 st year! Geant 4 usage for medical applications in Italy – – – Bari, Cagliari, Catania, Cosenza, Cuneo, Genova, ISS, Pisa, Torino, Trieste… small community w. r. t. much larger usage in Europe, America, Australia, Japan limiting factor: medical physics students not involved in Monte Carlo developments Next Geant 4 Course: Pisa, 12 January 2006 – – Proposal: Geant 4 course at ISS in 2006? Course in advanced software technology? Maria Grazia Pia, INFN Genova