Overview of AIDA in Geant4 bio-medical applications

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Overview of AIDA in Geant4 bio-medical
applications
Susanna Guatelli Univ. and INFN Genova CERN/IT/API
A collection of contributions from various user
groups
AIDA Workshop CERN, 3/6/2002
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Collaborations

• National Institute for Cancer Research IST,
  Genova
• S. Agostinelli, F. Foppiano, S. Garelli, M.
  Tropeano
• San Paolo Hospital, Savona
• G. Ghiso, S. Guatelli, R. Martinelli
• Azienda Ospedaliera (Hospital ) of Cosenza
• G. Barca, M. Veltri
• Physics Dept., UNICAL INFN, Cosenza
• F. Castrovillari, D. Cuce, E. Lamanna
• with the help of M.G. Pia (INFN Genova) and A.
  Pfeiffer (CERN)

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Brachytherapy
Brachytherapy is a medical therapy used for
cancer treatment
Radioactive sources are used to deposit
therapeutic doses near tumors, while preserving
surrounding healthy tissues
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Specific facilities controlled by a friendly UI
Advanced functionalities
Extensibility to accommodate new user
requirements (thanks to the OO technology)
A rigorous software process
What in a software system is relevant to the
bio-medical community?
Quality Assurance based on sound software
engineering
The transparency of physics
Independent validation by a large user community
worldwide
Use of evaluated data libraries
User support from experts
Adoption of standards wherever available (de
jure or de facto)
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Geant4 for simulation
Choice

AIDA (Anaphe ) for analysis
AIDA
Why AIDA

• Abstract interfaces no dependence from a
  specific product
• Components architecture
• Possibility to use different systems without
  modifying the code

• Why Anaphe
• CERN product
• User support
• Rigorous software engineering

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Protocols in radiotherapy
The IST group follows the direction of Basic
Dosimetry on Radiotherapy with Brachytherapy
Source of the Italian Association of Biomedical
Physics (AIFB)
Strict protocols
The Savona group follows the direction of the
dosimetry protocol for brachyterapy of the
American Association of Physicists in Medicine
(AAPM ) Task Group 43
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Photon attenuation vs. NIST data
Testing and Validation by IST - Natl. Inst. for
Cancer Research, Genova
Pb
water
Fe
Courtesy of S. Agostinelli, R. Corvo, F.
Foppiano, S. Garelli, G. Sanguineti, M. Tropeano
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Carcinoma treatment with brachyterapy

• Endocavitary brachytherapy ?
• 
  
• 
  

Anisotropic distribution of dose IST
Uterus, vagina, lung

• Superficial brachytherapy ?

Dose distribution no commercial software
available IST
Skin
Dose distribution High dose gradient release of
the source San Paolo Hospital (SAVONA)

• Interstitial brachytherapy ?

Prostate
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brachytherapy example (distributed
with Geant4 source code)
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Simulation set-up

• The source is in the center of a water box (side
  30 cm).
• The energy absorbed by the medium on the plane
  containing the source is stored in a matrix
• (locally deposited energy versus position).
• LowEnergy electromagnetic processes for all
  particles.

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Endocavitary brachytherapy
Source anisotropy
Treatment planning systems include algorithms to
account for source anisotropy
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• Role of the simulation

precise evaluation of the effects of source
anisotropy in the dose distribution
Role of analysis tool comparison
between histograms of the simulation and
reference data
2D histograms and their manipulation, fitting etc.
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Validation of the software
S. Agostinelli, F. Foppiano, S. Garelli, M.
Tropeano
Longitudinal axis of the source Difficult to make
direct measurements rely on simulation for better
accuracy than conventional treatment planning
software

• Transverse axis of the source
• Comparison with experimental data

Effects of source anisotropy
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Source anisotropy
F(?)
Plato-BPS treatment planning algorithm makes some
crude approximation (? dependence, no radial
dependence)
Courtesy of S. Agostinelli, R. Corvo, F.
Foppiano, S. Garelli, G. Sanguineti, M. Tropeano,
IST Genova
Plato treatment planning
Work in progress
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Superficial brachyterapy
No commercial sofware existing for these
applicators!
Dose distribution
Leipzig applicators

• Code reuse
• still the same application as in the previous
  case
• only difference the implementation of the
  geometry of the applicator, derived from the same
  abstract class

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Validation of the software

Experimental validation Geant4 Nucletron
data IST data
Dose distribution
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Brachytherapy at the Hospital of Savona G.
Ghiso, S. Guatelli, R. Martinelli

• A project in progress for the simulation with
  of brachytherapy 125I sources
  for prostate cancer therapy
• comparison with experimental data and
• with reference data (NIST)
• Precise dose distribution of the source
• 3D dose distribution generated by several
• sources placed in a volume

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Validation of the software

• Tests on low-energy processes
• (Simulation of e- ranges in different media)
• Comparison with NIST data and experimental data
  taken at the Savona Hospital

With AIDA 2.2 Anaphe 4.0.1
Preliminary!!!
Work in progress !
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An analysis use case in brachytherapy

• The energy absorbed by the the detector is stored
  in a 2D histogram (energy versus position in the
  plain containing the source)
• The initial energy of primary particles is
  stored in a 1D histogram

AIDA2.2
Next steps with analysis 3D dose distribution
Extraction of isodose curves from the
ntuple Publication-quality plots
Work in progress !
AIDAAnaphePython
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IORT(Intra-Operatory Radiation Therapy)
G. Barca, F. Castrovillari, D. Cucè, E.
Lamanna, M. Veltri Azienda Ospedaliera
(Hospital) of Cosenza Physics Dep., UNICAL
INFN, Cosenza
simulation in the framework of the
Italian IORT project

• The Italian IORT Project
• funded by the Italian Ministry of Research
  (MURST),
• started in 1998 by ENEA (Italian National Agency
  for New Technologies, Energy and the Environment)
• design and construct an innovative IORT system
  (IORT1), as an improvement to the current
  IORT-NOVAC7 system, jointly developed by ENEA and
  Hitesys

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• An advanced radiotherapy technique utilising an
  electron beam (produced by a linear accelerator)
  to obtain the sterilisation of the tumour bed, by
  delivering a single high dose of radiation
  during oncological surgery

IORT Novac7

• a robotic mobile intraoperative beam unit
• based on an electron beam linear accelerator
  utilising an autofocusing structure
• 4MeV to 9MeV electrons

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Metabolic Therapy with 131I

• Therapy applied at Cosenza Hospital for thyroid
  diseases
• nodules, carcinoma, disorders in general
• Isotope accumulated in the damaged lobe can
  destroy pathological cells without any surgical
  operation
• Take advantage of the radioactive properties of
  131I and of the metabolic capability of the
  thyroid

131I ? 131Xe ?- ?
G. Barca, F. Castrovillari, D. Cucè, E.
Lamanna, M. Veltri Azienda Ospedaliera
(Hospital) of Cosenza Physics Dep., UNICAL
INFN, Cosenza
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Role of the Simulation

• Define the geometrical structure of the set-up
• Track
• ? and ?- from the Nodule-Source to the other
  thyroid cells
• the reactions of biological tissues to the
  accumulated 131I
• Obtain information to calculate the best dose to
  release to the patient

Real Thyroid
Simplified model
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Technology transfer
CERN Courier, June 2002
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Conclusions

• Rigorous software engineering, quality assurance
  and standards are important in the medical
  physics domain
• Various applications of Geant4 AIDA (Anaphe) in
  medical physics
• Role in clinical practice in hospitals