1 geant4@parisgeant4@paris 08/06/2007 // this : a geant4-based therapeutic

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Geant4@Paris 08/06/2007 http://www.creatis.insa-lyon.fr/rio/ThIS/

ThIS : a Geant4-basedTherapeutic Irradiation Simulator

Laurent Guigues

CREATIS, UMR CNRS 5220, INSERM U 630Villeurbanne, France

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Outline

Introduction Goal Architecture

ThIS modules Physics Geometry Sensors Beam

Conclusion

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Goal of the project Rationale :

Several radiotherapy studies involve MC simulations

Multidisciplinary research (physics, medicine, computer science...)

Computer science difficulties (C++) Share development

Goal : Monte-Carlo simulation platform for radiation

therapy studies Photon, Proton, Carbon Cooperative work Accuracy, speed, ease of use, flexibility,

openness ...

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Some technical choices

Geant4 Extensive and extensible physics C++

Associated with an image library : ThISiS (ThIS image suite) Managing 3D volumes :

CT images 3D dose maps

ITK-based http://www.itk.org(Insight Segmentation and Registration Toolkit) Command line only (no display)

Documentation wiki, CVS development (cooperative)

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ThIS is easy ! High-level macro language (“à la

GATE”) : [Jan et al. 2004] “GATE: a simulation toolkit for

PET and SPECT” Phys. Med. Biol. 49 (2004) 4543-4561.

GATE : Geant4 Application for Tomographic Emission Focused on PET, SPECT simulations

ThIS : Therapeutic Irradiation Simulator Focused on radiation therapy simulations

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ThIS is easy !

Running a simulation :

ThIS MyBeautifulSimu.mac “/run/beamOn 100”

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/this/physics/Gamma/SetCutInRegion world 10.0 mm/this/physics/Electron/SetCutInRegion waterBox 3.6 mm/this/physics/Positron/SetCutInRegion PMMACone 4.0 cm# A linac/this/scene/addVolume AcceleratorHead linac/this/scene/linac/parent world/this/scene/linac/position 0 0 100 cm/this/scene/linac/Target/Diameter 5.4 mm/this/scene/linac/Target/Thickness 1 mm/this/scene/linac/Target/Material Tungsten/this/scene/linac/PrimaryCollimator/Diameter 200 mm/this/scene/linac/PrimaryCollimator/Height 101 mm/this/scene/linac/PrimaryCollimator/BaseDiameter 62.9 mm

/this/scene/addSensor HitsAccumulatorsSensor mySensor/this/scene/mySensor/hitType post/this/scene/mySensor/attach waterBox/this/scene/mySensor/halfsize 7 15.0 7 cm/this/scene/mySensor/resolution 70 150 70/this/scene/mySensor/position 0.0 -15.0 0.0 cm/this/scene/mySensor/saveEveryNEvents 200/this/scene/mySensor/baseFilename output.hdr

/this/scene/mySensor/Edep/enable 1/this/scene/mySensor/Edep/uncertainty 1/this/scene/mySensor/Edep/squared 1

ThIS is easy !



File of macrosFile of macros

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/this/physics/Gamma/SetCutInRegion world 10.0 mm/this/physics/Electron/SetCutInRegion waterBox 3.6 mm/this/physics/Positron/SetCutInRegion PMMACone 4.0 cm# A linac/this/scene/addVolume AcceleratorHead linac/this/scene/linac/parent world/this/scene/linac/position 0 0 100 cm/this/scene/linac/Target/Diameter 5.4 mm/this/scene/linac/Target/Thickness 1 mm/this/scene/linac/Target/Material Tungsten/this/scene/linac/PrimaryCollimator/Diameter 200 mm/this/scene/linac/PrimaryCollimator/Height 101 mm/this/scene/linac/PrimaryCollimator/BaseDiameter 62.9 mm



ThIS is easy !



File of macrosFile of macros

No C++ No compilation

No C++ No compilation

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Documentation

User's GuideUser's Guide

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Using cutsUsing cuts

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ThIS' Architecture

Based on Geant4 classes

Extend functionality with ThIS classesintermediate level between Geant4 and the user

Provide user macros interaction

Geant4

Core

Classes

ThIS Core Classes

ThIS Macros

Developer

End User

script

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ThIS' Architecture

ThIS is made up of 5 modules :

Simulation Manager : verbosity, display... Physics : particles, processes and models declaration Scene : description of the content of the world : volumes, materials (patient, beam line...) Beam : description of the particle beam : type of particles, energy spectrum, shape of the beam... Sensors : information that you wish to gather during the simulation(e.g. #of neutrons created in a given volume, spectrum of the gammas produced, energy deposited in some region...). Sensors are activated by Triggers.(similar to G4 Scorers and Filters) Volume 1 Sensor 1

TriggerPhysicsworld

Volume n Sensor m

……Beam

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Main modules

Main modules Physics Geometry (scene) Sensors & Triggers Beam

Run-time vs Compile-time

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Physics module

ThISPhysicsList :

Manage 2 main lists : List of groups of particles List of physical processes

Associate at run-time one group of particles with a process according to user's choices

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Physics module

ThISPhysicsList :

Manage 2 main lists : List of groups of particles

Groups defined with a predicate

Can have n particules (including 1) List of physical processes

particle->GetParticleName() == “e-”

particle->GetPDGCharge() != 0.0

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Physics module

ThISPhysicsList :

Manage 2 main lists : List of groups of particles List of physical processes

A “process” is composed of a name some “models” some parameters

Example : Compton

Standard = G4ComptonScattering LowEn = G4LowEnergyCompton Penelope = G4PenelopeCompton

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Physics module

ThISPhysicsList :

Manage 2 main lists : List of groups of particles List of physical processes/this/physics/Gamma/PhotoElectric/lowE/this/physics/Gamma/Compton/lowE/this/physics/Gamma/GammaConversion/lowE/this/physics/Gamma/Rayleigh/lowE

/this/physics/Electron/MultipleScattering/standard/this/physics/Electron/eIonisation/lowE/this/physics/Electron/eBremsstrahlung/lowE

/this/physics/Positron/MultipleScattering/standard/this/physics/Positron/eIonisation/standard/this/physics/Positron/eBremsstrahlung/standard/this/physics/Positron/eplusAnnihilation/standard

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Physics module

ThISPhysicsList :

Manage 2 main lists : List of groups of particles List of physical processes/this/physics/Gamma/PhotoElectric/lowE/this/physics/Gamma/Compton/penelope/this/physics/Gamma/GammaConversion/lowE/this/physics/Gamma/Rayleigh/lowE

/this/physics/Electron/MultipleScattering/standard/this/physics/Electron/eIonisation/lowE/this/physics/Electron/eBremsstrahlung/lowE

/this/physics/Positron/MultipleScattering/standard/this/physics/Positron/eIonisation/standard/this/physics/Positron/eBremsstrahlung/standard/this/physics/Positron/eplusAnnihilation/standard

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Physics module

ThISPhysicsList : Some hadronic processes (elastic/inelastic) Not all G4 hadronic processes included (yet)

/this/physics/Proton/hadronElastic/standard/LElastic/this/physics/Proton/protonInelastic/standard/BinaryCascade/SetMinEnergy 170 MeV/this/physics/Proton/protonInelastic/standard/BinaryCascade/SetMaxEnergy 500 MeV/this/physics/Proton/protonInelastic/standard/PreCompoundModel/SetMinEnergy 0 MeV/this/physics/Proton/protonInelastic/standard/PreCompoundModel/SetMaxEnergy 170 MeV

/this/physics/GenericIon/genericIonInelastic/standard/BinaryLightIonReaction

/this/physics/Deuteron/hadronElastic/standard/LElastic/this/physics/Deuteron/hadronFission/standard/LFission

/this/physics/Deuteron/deuteronInelastic/standard/BinaryLightIonReaction/SetMinEnergy 80 MeV/this/physics/Deuteron/deuteronInelastic/standard/BinaryLightIonReaction/SetMaxEnergy 20 GeV/this/physics/Deuteron/deuteronInelastic/standard/LEDeuteronInelastic/SetMinEnergy 0 MeV/this/physics/Deuteron/deuteronInelastic/standard/LEDeuteronInelastic/SetMaxEnergy 1000 MeV

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Physics module

ThISPhysicsList : Some hadronic processes (elastic/Inelastic) Not all G4 hadronic processes included (yet)

Simple mechanism to add processes from G4 (compile-time) to ThIS (run-time)

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Physics module



// C++ MacrosADD_DISCRETE_PROCESS(ThIS_PhotoElectricEffect_std_PB, PhotoElectric, standard, G4PhotoElectricEffect, ThISPhotonParticlesGroupBuilder);

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Physics module




User macro nameUser macro nameGroup of particleGroup of particleStandard G4 process nameStandard G4 process name

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Physics module




User macro nameUser macro nameGroup of particleGroup of particle

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Physics module




User macro nameUser macro name

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Physics module

ThISPhysicsList : Output user selected physics

/this/physics/particleGroupOutput particles-groups.txt/this/physics/particleOutput particles-list.txt/this/physics/processGroupOutput process-groups.txt/this/physics/processOutput process-list.txt/this/physics/particleProcessOutput particle-process.txt

Output available

particles/processes at compile-time

Output available

particles/processes at compile-time

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Physics module

ThISPhysicsList : Output user selected physics

/this/physics/particleGroupOutput particles-groups.txt/this/physics/particleOutput particles-list.txt/this/physics/processGroupOutput process-groups.txt/this/physics/processOutput process-list.txt/this/physics/particleProcessOutput particle-process.txt

Output user enabled

particles/processes at run-time

Output user enabled

particles/processes at run-time

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Physics module

Gamma (1) : gamma Electron (1) : e- Positron (1) : e+ Neutron (1) : neutron GenericIon (1) : GenericIon Proton (1) : proton Ions (4) : He3 alpha deuteron triton Baryons (32) : anti_lambda anti_lambda_c+ anti_neutron ...Mesons (24) : B+ B- B0 Bs0 D+ D- D0 Ds+ Ds- J/psi anti_B0...Leptons (12) : anti_nu_e anti_nu_mu anti_nu_tau e+ e- mu+ ...Deuteron (1) : deuteron Triton (1) : triton Alpha (1) : alpha He3 (1) : He3 HadronElasticApplicable (28) : alpha anti_lambda anti_neutron...IonIonisationApplicable (5) : GenericIon He3 alpha deuteron ...ChargedAndNotShortLived (39) : B+ B- D+ D- Ds+ Ds- GenericIon ......

Example of some available

groups of particles


groups of particles

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Physics module

PhotoElectric-standard : gamma PhotoElectric-lowE : gamma PhotoElectric-penelope : gamma Compton-std : gamma Compton-lowE : gamma Compton-penelope : gammaRayleigh-lowE : gamma Rayleigh-penelope : gamma MultipleScattering-standard : B+ B- D+ D- Ds+ Ds- GenericIon He3 alpha ...eIonisation-standard : e+ e- eIonisation-lowE : e- eIonisation-penelope : e+ e- eBremsstrahlung-standard : e+ e- eBremsstrahlung-lowE : e- eBremsstrahlung-penelope : e+ e- eplusAnnihilation-standard : e+ eplusAnnihilation-penelope : e+ ionIonisation-standard : GenericIon He3 alpha deuteron triton hadronIonisation-standard : B+ B- D+ D- Ds+ Ds- GenericIon He3 alpha ...genericIonInelastic-standard : GenericIon neutronInelastic-standard : neutron deuteronInelastic-standard : deuteron tritonInelastic-standard : triton alphaInelastic-standard : alpha He3Inelastic-standard : He3 protonInelastic-standard : proton


processes


processes

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Physics module

GenericIon : MultipleScattering-standard ionIonisation-standard genericIonInelastic-standard(BinaryLightIonReaction[min=def,max=def])

deuteron : MultipleScattering-standard ionIonisation-standard hadronElastic-standard(LElastic[min=def,max=def]) hadronFission-standard(LFission[min=def,max=def]) deuteronInelastic-standard(BinaryLightIonReaction[min=80,max=20000]LEDeuteronInelastic[min=0,max=1000])

e+ : MultipleScattering-standard eIonisation-standard eBremsstrahlung-standard eplusAnnihilation-standard

e- : MultipleScattering-standard eIonisation-lowE eBremsstrahlung-lowE

gamma : PhotoElectric-lowE Compton-lowE GammaConversion-lowE Rayleigh-lowE

neutron : hadronElastic-standard(LEpp[min=def,max=def]) hadronNeutronCapture-standard(LCapture[min=def,max=def]) hadronFission-standard(LFission[min=def,max=def]NeutronHPFission[min=def,max=def])

proton : MultipleScattering-standard hadronIonisation-ziegler2000 hadronElastic-standard(LElastic[min=def,max=def]) protonInelastic-standard(BinaryCascade[min=170,max=500]PreCompoundModel[min=0,max=170])

Example of some user

selected processes

Example of some user

selected processes

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Physics module

ThISPhysicsList : Still several G4 processes to be added But the main mechanisms exist Collaborative work based on user interest

principle : If you need it : add it So : everyone can use it

Drawback : No checking of the physics list validity (except

IsApplicable from G4)

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Cuts

Setting cuts in ThIS Production cuts MaxStepLimiter “cuts” Killing cuts

/this/physics/Gamma/SetCutInRegion world 10.0 mm/this/physics/Electron/SetCutInRegion waterBox 3.6 mm/this/physics/Positron/SetCutInRegion PMMACone 4.0 cm

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Cuts


/this/physics/Gamma/SetCutInRegion world 10.0 mm/this/physics/Electron/SetCutInRegion waterBox 3.6 mm/this/physics/Positron/SetCutInRegion PMMACone 4.0 cm

Previously user

defined volumes

Previously user

defined volumes

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Cuts


/this/physics/UserLimits/SetMaxAllowedStep world 2 mm/this/physics/UserLimits/SetMaxAllowedStep waterBox 1 mm/this/physics/Electron/StepLimiter/standard/this/physics/Gamma/StepLimiter/standard

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Cuts


/this/physics/UserLimits/SetMaxAllowedStep world 2 mm/this/physics/UserLimits/SetMaxAllowedStep waterBox 1 mm/this/physics/Electron/StepLimiter/standard/this/physics/Gamma/StepLimiter/standard

MaxStep limiter for each

region, for each particle

MaxStep limiter for each

region, for each particle

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Cuts


/this/physics/UserLimits/SetUserMinRange waterBox 0.1 mm/this/physics/UserLimits/SetUserMinRange world 1 mm/this/physics/UserLimits/SetUserMinEkine waterBox 10 keV/this/physics/UserLimits/SetUserMinEkine world 100 keV/this/physics/Electron/UserSpecialCuts/standard

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Cuts


/this/physics/UserLimits/SetUserMinRange waterBox 0.1 mm/this/physics/UserLimits/SetUserMinRange world 1 mm/this/physics/UserLimits/SetUserMinEkine waterBox 10 keV/this/physics/UserLimits/SetUserMinEkine world 100 keV/this/physics/Electron/UserSpecialCuts/standard

“Kill” particle according to

range/energy threshold

“Kill” particle according to

range/energy threshold

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Main modules



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Main modules



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#=================================================# World volume/this/scene/addVolume Box world/this/scene/world/halfsize 2 2 2 m/this/scene/world/material_name Air

#=================================================# A water box/this/scene/addVolume Box waterBox/this/scene/waterBox/parent world/this/scene/waterBox/position 0.0 0.0 0.0 cm/this/scene/waterBox/halfsize 15.0 15.0 15.0 cm/this/scene/waterBox/material_name Water

Scene module

ThISDetectorConstructor : Dynamic (run-time) scene description Add volumes Set properties (position, material ...)

Volume typeVolume type

Volume nameVolume name

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Scene module

ThISDetectorConstructor : Some G4 simple shapes (Box, Cone ...)

#=================================================# A PMMA cone/this/scene/addVolume Cone PMMACone/this/scene/PMMACone/parent world/this/scene/PMMACone/position 5.0 -3.0 40.0 cm/this/scene/PMMACone/rmin1 0 cm/this/scene/PMMACone/rmax1 3.7 cm/this/scene/PMMACone/rmin2 0 cm/this/scene/PMMACone/rmax2 0 cm/this/scene/PMMACone/dz 78 mm/this/scene/PMMACone/sphi 0 deg/this/scene/PMMACone/dphi 22 deg/this/scene/PMMACone/material_name PMMA



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Scene module

ThISDetectorConstructor : Some G4 simple shapes (Box, Cone ...) Complex user defined shapes (in progress)

#=================================================# An linac/this/scene/addVolume AcceleratorHead linac/this/scene/linac/parent world/this/scene/linac/position 0 0 100 cm/this/scene/linac/Target/Diameter 5.4 mm/this/scene/linac/Target/Thickness 1 mm/this/scene/linac/Target/Material Tungsten/this/scene/linac/PrimaryCollimator/Diameter 200 mm/this/scene/linac/PrimaryCollimator/Height 101 mm/this/scene/linac/PrimaryCollimator/BaseDiameter 62.9 mm/this/scene/linac/FlatteningFilter/ConeDiameter 54.4 mm...

Volume typeVolume type Volume nameVolume name

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Scene module




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Scene module




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Scene module




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Scene module

ThISDetectorConstructor : Some G4 simple shapes (Box, Cone ...) Complex user defined shapes (in progress) Simple mechanism to add volumes from G4

(compile-time) to ThIS (run-time) Collaborative work based on user’s interest


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Scene module

/this/scene/object/this/scene/object/parent

/this/scene/addVolume/this/scene/object/material

/this/scene/object/position/this/scene/object/rotation

/this/scene/object/halfsize

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Scene module

class ThISBoxVolume : public ThISVolume{

public:ThISBoxVolume(ThISDetectorConstruction* dc, G4String path, G4String name);~ThISBoxVolume();

THISMACRO_INIT_VOLUME_CREATOR(ThISBoxVolume);

virtual G4String GetTypeName() { return "Box";}virtual void ConstructSolid();

void SetHalfSize(G4ThreeVector v) { mHalfSize = v; }G4ThreeVector GetHalfSize() const { return mHalfSize; }

void PrintInfo();protected:

ThISBoxVolumeMessenger * pMessenger;G4ThreeVector mHalfSize;

ThISBoxVolume(); };

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Scene module

//============================================================ThISBoxVolume::ThISBoxVolume ( ThISDetectorConstruction* dc, G4String path, G4String name )

: ThISVolume(dc,path,name) {

mHalfSize = G4ThreeVector(0.5*m, 0.5*m, 0.5*m);pMessenger = new ThISBoxVolumeMessenger(this);

}//============================================================ThISBoxVolume::ThISBoxVolume()

: pMessenger(0){}//============================================================ThISBoxVolume::~ThISBoxVolume() {

if (pMessenger) delete pMessenger;}//============================================================void ThISBoxVolume::ConstructSolid(){

G4String solidName = GetInstanceName()+"_solid";SetSolid ( new G4Box (solidName, mHalfSize.x(), mHalfSize.y(), mHalfSize.z()) );

}//============================================================void ThISBoxVolume::PrintInfo(){

ThISVolume::PrintInfo();std::cout << "\t HalfSize = " << G4BestUnit(GetHalfSize(),"Length") << std::endl;

}//============================================================

From ThISNamedObjectFrom ThISNamedObject

From ThISVolumeFrom ThISVolume

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Scene module

class ThISBoxVolumeMessenger: public ThISVolumeMessenger{

public:ThISBoxVolumeMessenger ( ThISBoxVolume* box );~ThISBoxVolumeMessenger();void SetNewValue ( G4UIcommand*, G4String );

protected:ThISBoxVolume * boxVolume;G4UIcmdWith3VectorAndUnit * halfsizeCmd;

};//===============================================================ThISBoxVolumeMessenger::ThISBoxVolumeMessenger ( ThISBoxVolume* box )

: ThISVolumeMessenger(box), boxVolume(box){

G4String name = boxVolume->GetInstanceName();G4String path = boxVolume->GetPath();

G4String n = path+"/halfsize";halfsizeCmd = new G4UIcmdWith3VectorAndUnit(n, this); halfsizeCmd->SetGuidance(G4String("Set "+name+"’s size"));halfsizeCmd->SetDefaultUnit("cm");

}//===============================================================void ThISBoxVolumeMessenger::SetNewValue ( G4UIcommand* command, G4String newValue ){

if ( command == halfsizeCmd )boxVolume->SetHalfSize(halfsizeCmd->GetNew3VectorValue(newValue));

else ThISVolumeMessenger::SetNewValue(command,newValue);

}

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Scene module

ThISDetectorConstructor : Some G4 simple shapes (Box, Cone ...) Complex user defined shapes (in progress) Simple mechanism to add volumes from G4

(compile-time) to ThIS (run-time) Collaborative work based on user’s interest


Materials : Re-use the Material Database mechanism from

Gate (enhanced to allow multiple Dbs)

/this/scene/materialDatabase StandardMaterials.db/this/scene/materialDatabase PhantomMaterials.db

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Scene module

ThISDetectorConstructor : Easy to add elements/materials

[Elements]

Hydrogen: S= H ; Z= 1. ; A= 1.01 g/moleHelium: S= He ; Z= 2. ; A= 4.003 g/moleCarbon: S= C ; Z= 6. ; A= 12.01 g/moleNitrogen: S= N ; Z= 7. ; A= 14.01 g/mole

[Materials]

PMMA: d=1.195 g/cm3; n=3 ; state=Solid +el: name=Hydrogen ; f=0.080541 +el: name=Carbon ; f=0.599846 +el: name=Sulfur; f=0.319613

Gadox: d=7.23 g/cm3; n=4 ; state=Solid +el: name=Gadolinium ; f=0.736 +el: name=Sulfur ; f=0.149 +el: name=Oxygen; f=0.112

+el: name=Terbium; f=0.003

GateMaterials.dbGateMaterials.db

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Scene module

ThISDetectorConstructor : Insert CT image in simulation

CT slices

Geant4 /

ThIS

Geant4 /

ThIS

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Scene module

Insert images in simulation

1. Transform CT image into composition image

1. Calibrate Scanner using phantom [schneider et al. 2000]

2. Transform CT image : => image of labels + label to material table

=> Provided in ThISiS

1. Insert label image in G4 simulation

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Scene module

Insert images in simulation

1 G4Box per voxel !! High memory cost : not feasible in real-world cases

ParametrisedVolume / NestedParametrisedVolume

Low memory cost, G4 state-of-the-art, Time consuming

Two ways to reduce time1) Reduce image complexity2) Change G4 navigation algorithm

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Scene module

Insert images in simulation1) Reduce image complexity2) Change G4 navigation algorithm

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Scene module

Insert images in simulation1) Reduce image complexity

Voxels

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Scene module


Merge adjacent voxels having similar materials :Image Segmentation problem

Voxels

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Scene module



a) Isothetic Volume : Segment image in parallelepipeds (G4Box) Special case : Octree segmentation [Hubert-

Tremblay et al. 2006]

Isothetic OctreeVoxels

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Scene module



a) Isothetic Volume : Segment image in parallelepipeds (G4Box) Special case : Octree segmentation [Hubert-

Tremblay et al. 2006]b) Regionalised Volume : arbitrary shape

[Sarrut and Guigues subm.]

Isothetic OctreeVoxels Regions

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Scene module



Segmentation methods available in ThISiS


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Scene module


Available image representations in ThIS :- ImageBoxes (multiple G4Box)- ImageParameterised (G4VParameterisedVolume) - ImageNestedParameterised

(G4VNestedParam...Volume)- ImageIsothetic- ImageRegionalised


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Scene module

Insert images in simulation Image volumes

Label image (Analyze, raw formats ...) Label to material information

/this/scene/addVolume ImageBoxes patient/this/scene/patient/parent world/this/scene/patient/image lung.hdr/this/scene/patient/materials lung.lab2mat

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Scene module






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Scene module






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Scene module






0 Air1 Lung2 SoftTissue...8 ConnectiveTissue9 Bone_110 Bone_2...

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Scene module

Results

Octree

Arbitrary regions

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Scene module

Results

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Scene module

Results

Speed up

(time NPV

/ time RV)

Dose difference RV-NPV (%)

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Scene module


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Scene module


[Jiang & Paganetti 2004] : in progress

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Scene module

Image volumes : Tradeoff :

Accuracy / Speed Large number of regions :

small compression, slow simulation good accuracy

Small number of regions : good compression, fast simulation low accuracy

Still a lot to of work to be done

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Scene module ThISDetectorConstructor :

Done : main mechanism simple base shapes / complex volumes

To do : Boolean operations Add other shapes

Image volumes Associated image preparation tools (ThISiS)

Calibration Segmentation

Optimized volumes ImageIsothetic (octree segmented images) ImageRegionalised (segmented images)

Optimized navigator : in progress

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Main modules



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Main modules



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Sensor module

ThISSensor

ThIS DOES NOT use the G4SensitiveDetector mechanism

Sensor = measure/display Something : dose deposit (uncertainty),

number of B+ emitters ... Somewhere : globally, in a volume, surface ... Sometimes : at the end of the simulation, at

each track, at each steps, every n events ...

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Sensors module

Triggers All sensors can be associated with a trigger :

Including, excluding particle from a measurement Sorting on energy ...

/this/scene/addTrigger ParticleName T2/this/scene/T2/include all/this/scene/T2/exclude e-/this/scene/T2/exclude gamma/this/scene/T2/exclude proton

/this/scene/addTrigger ParticleEnergy T3/this/scene/T3/energyMin 100 keV/this/scene/T3/energyMax 10 TeV

/this/scene/addTrigger And T4/this/scene/T4/add T2/this/scene/T4/add T3

/this/scene/ANYSENSOR/trigger T4

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Sensors module







All particles

except e-,

gamma, proton

All particles

except e-,

gamma, proton

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Sensors module







With energy

in this range

With energy

in this range

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Sensors module

ThISSensor

Two examples of sensors :

Particles counter Dose sensor (energy deposited + uncertainty)

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Sensors module

ThISParticleCounter

/this/scene/addSensor ParticleCounter MyCounter/this/scene/MyCounter/track pre/this/scene/MyCounter/attach waterBox/this/scene/MyCounter/verbose/event 1

Sensor typeSensor type

Sensor nameSensor name

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Sensors module

> ThIS MySimu.mac “/run/beamOn 5”R1 ****************** Begin of run 1 ********************B1 ======= Generating particle 1=======B2 _ (1) C12[0.0] pos.=(-1.19545,201.124,0) energy=2640 dir.=(0,-1,0)T0 C12 1 0 2.64 GeV 0 fmT0 C12 1 0 0 eV 15.1 cmT0 e- 1022 1 87.9 keV 0 fm ionIoniT0 e- 1021 1 0 eV 390.6 mum ionIoniT0 e- 1020 1 93.3 keV 0 fm ionIoniT0 e- 1020 1 0 eV 393.3 mum ionIoniT0 e- 1019 1 96.3 keV 0 fm ionIoniT0 e+ 921 919 11.3 MeV 0 fm LowEnConversionT0 e+ 921 919 0 eV 4.4 cm LowEnConversionT0 e- 1016 1 0 eV 2.2 mm ionIoniT0 e- 768 1 0 eV 949.4 mum ionIoniT0 gamma 1023 768 3.2 keV 0 fm LowEnBremT0 gamma 1023 768 0 eV 9.2 mum LowEnBremT0 e- 1024 1023 2.6 keV 0 fm LowEnPhotoElecT0 e- 1024 1023 0 eV 1.4 mm LowEnPhotoElecT0 e- 767 1 136.3keV 0 fm ionIoni

Output Kinetic energyKinetic energy

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Sensors module


Output Track lengthTrack length

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Sensors module


Output Creator processCreator process

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ExampleB10 220

B11 647

B12 8

B13 15

B14 1

B15 1

B5 1

B9 28

C10 112

C11 780

C12 11663

C13 444

C14 296

C15 8

C16 5

C6 1

C9 5

N11 3

N12 3

N13 71

N14 407

N15 782

N16 37

N17 1

proton 205703

neutron 53128

H2 5

H3 2

H4 9

deuteron 1320

triton 265

He2 5

He3 291

He4 2

He5 17

He6 24

He8 3

alpha 5810

Li3 1

Li4 16

Li5 34

Li6 66

Li7 137

Li9 6

Be10 152

Be11 1

Be12 2

Be4 1

Be5 1

Be6 24

Be7 108

Be8 1195

Be9 65

O13 12

O14 111

O15 523

O16 3218

O17 141

O18 11

F15 9

F16 17

F17 7

F19 1

Ne16 1

Ne18 3

Ne20 9

Ne21 1

Ne22 1

e- 935202

gamma 63306

e+ 1321

anti_nu_e 24

pi0 1

Production for 10 000 C12

(220 MeV/u), in water

(Nuclear reaction : 39 %)

Production for 10 000 C12

(220 MeV/u), in water

(Nuclear reaction : 39 %)

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Sensors module

Dose / Edep measurement sensor Define a 3D matrix Store information (edep, dose ...) and

associated uncertainty Allow to dump in files every n events Several accumulation types

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Sensors module

Dose / Edep measurement



Type / NameType / Name

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Sensors module




Accumulation typeAccumulation type

89


Sensors module




Size, resolution, positionSize, resolution, position

90


Carbon depth dose (Bragg peak)

Example

91


Sensors module

Like for the physics and geometry modules, new Sensors and Triggers are very easily created

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Conclusion

ThIS is a Geant4-based Therapeutic Irradiation Simulator :

Make G4 features available at run-time Designed to be easily extensible Easy to use : no C++, easy scripting Ideal for prototyping, testing, running large

numbers of simulations with different parameters...

Optimised for image-based simulations

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Conclusion

ANR grant funding : “SimCa2 : Simulation for Cancer therapy by

Carbon beams” Full time computer science engineer for ThIS

Collaborations Geant4 France group (Sébastien Incerti) OpenGate collaboration (Irène Buvat, ...)

Share common developments

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Future Work

Intensive validation ! Optimized navigation in images Cluster / grid version : in progress Repository of beam lines ...

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Openness

ThIS is an Open Source project Cooperative spirit :

CVS repository Wiki documentation Repository of Beam Lines ? Share experiences ?

Try It !If you are interested, contact us

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Thank you for your attention

Any question ?

1 geant4@parisgeant4@paris 08/06/2007 // this : a geant4-based therapeutic

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