Experience in Medical Physics

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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 Geant4-INFN Group

• Sistemi di Calcolo Avanzato per la Pratica
  Clinica e la Ricerca in Fisica Medica
• Istituto Superiore di Sanità
• Roma, 13 December 2005

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Born from the requirements of large scale HEP
experiments
Object Oriented Toolkit for the simulation of
particle interactions with matter

• 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

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

• RD phase RD44, 1994 - 1998
• 1st release December 1998
• 2 new releases/year since then

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in a nutshell

• Rigorous software engineering
• Iterative-incremental software process
• Object oriented methods
• Quality assurance
• Geometry
• 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
• Visualisation, UI/GUI
• Multiple drivers to external systems

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Geant4 Collaboration
100 members

• MoU based
• Development, Distribution and User Support of
  Geant4

• Major physics laboratories
• CERN, KEK, SLAC, TRIUMF, TJNL
• European Space Agency
• ESA
• National Institutes
• INFN, IN2P3, PPARC
• Universities
• Budker Inst., Frankfurt, Karolinska Inst.,
  Helsinki, Lebedev Inst., LIP, Lund, Northeastern
  etc.

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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
Hadrontherapy
Brachytherapy
Courtesy of S. Guatelli et al,. INFN Genova
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Comparison of Geant4 electromagnetic physics
models against the NIST reference data IEEE
Transactions on Nuclear Science, vol. 52 (4), pp.
910-918, 2005
Geant4 electromagnetic physics models are
accurate Compatible with NIST data within NIST
accuracy (LowE p-value gt 0.9)
Results All Geant4 models compatible with
NIST Best agreement Geant4 LowE models
p-value stability study
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http//www.ge.infn.it/geant4/dna
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for medicine

• Macroscopic
• calculation of dose
• medical imaging
• already feasible with Geant4
• develop useful associated tools
• Cellular level
• cell modelling
• processes for cell survival, damage etc.
• DNA level
• DNA modelling
• physics processes at the eV scale
• processes for DNA strand breaking, repair etc.

Complexity of software, physics and
biology addressed with an iterative and
incremental software process
Parallel development at all the three
levels (domain decomposition)
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Geant4 in a distributed computing environment

• Geant4 applications running
• on a single computer,
• on a local farm,
• on the GRID
• Same code

Developed by J. Moscicki, CERN http//cern.ch/DIAN
E
Master-Worker model
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United Nations World Summit on Information
SocietyGeneva, December 2003
Geant4 INFN presentation
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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
Quality Assurance based on sound software
engineering
Extensibility to accommodate new user
requirements
What in HEP software is relevant to the
bio-medical community?
Independent validation by a large user community
worldwide
Transparency of physics
Adoption of standards wherever available
Use of evaluated data libraries
User support from experts
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Meditations

• Software for medical physics
• RD 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 1st year!
• Geant4 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 Geant4 Course Pisa, 12 January 2006
• Proposal Geant4 course at ISS in 2006?
• Course in advanced software technology?