1. Introduction of GATE
국립암센터
박 세 준 연구원

2. GATE 란 GATE : GEANT4 Application for Tomographic Emission
Geant4를 기반으로 하여 핵의학영상기기인 PET과 SPECT 시뮬레이션을 위하여 2004년 처음으로 release됨.
2010년 2월에 release된 GATE ver 부터 radiation therapy, hadron therapy 추가됨. (Currently GATE ver. 6.2)
GATE simulation
Sinogram
Reconstructed image

3. Main technical features
GATE
is based on Geant4
is written in C++
is user-friendly as simulations can be designed and controlled using macros, without any C++ writing
is able to simulate SPECT, PET and CT scans and radiotherapy treatments
is flexible enough to model almost any detector design
explicitly models time, therefore make it possible to model detector motion, patient motion, radioactive decay, optical photon tracking, dead time, time of flight, tracer kinetecs
can handle analytical or voxelized phantoms
can run on a cluster architecture and on a grid

4. How it works Developer level User level Core and Application layer
C++ programming
User level
Simulation parameters
Geometry
Sources
Time
Analysis …
Macro scripting only
Structure of GATE

5. General Simulation Architecture
Scanner geometry
Phantom geometry
Physics processes
Initialization compute cross-section tables
Digitizer Description
Source Description
Output setup
Time management
Materials ; Geometry ;
Physical processes
Post-initialization

6. Geometry scripting world scanner phantom
/gate/world/geometry/setXLength 100 cm
/gate/world/geometry/setYLength 100 cm
/gate/world/geometry/setZLength 100 cm
crystal
collimator
/gate/world/daughters/name SPECThead
/gate/world/daughters/insert box
/gate/SPECThead/repeaters/insert ring
/gate/SPECThead/ring/setRepeatNumber 4
/gate/SPECThead/daughters/name collimator
/gate/SPECThead/daughters/insert box
/gate/SPECThead/daughters/name crystal
/gate/SPECThead/daughters/insert box
/gate/world/daughters/name Phantom
/gate/world/daughters/insert cylinder

7. Ocular brachytherapy treatment
PET camera
Radiotherapy
Ocular brachytherapy treatment
Geometry example
OPET scanner

8. Material and Physics scripting
/gate/geometry/setMaterialDatabase ../../GateMaterials.db ……
# P H Y S I C S
#####
/gate/physics/addProcess PhotoElectric
/gate/physics/addProcess LowEnergyCompton
/gate/physics/addProcess LowEnergyRayleighScattering
/gate/physics/addProcess ElectronIonisation
/gate/physics/addProcess Bremsstrahlung
/gate/physics/addProcess MultipleScattering e-
/gate/physics/processList Enabled
/gate/physics/processList Initialized
/applic/application/hep/Gate/gate_v6.2/GateMaterials.db

9. Sensitive volumes and digitization
# S E N S I T I V E D E T E C T O R S
# Crystal SD
/gate/crystal/attachCrystalSD
# D I G I T I Z E R
#####
# The digitizer tracks what happens in the detection system and in the electronics
# Build a digitizer that first computes the centroid of interactions ##
/gate/digitizer/Singles/insert adder
/gate/digitizer/Singles/insert blurring
/gate/digitizer/Singles/blurring/setResolution 0.10
/gate/digitizer/Singles/blurring/setEnergyOfReference 140. keV
/gate/digitizer/Singles/insert spblurring
/gate/digitizer/Singles/spblurring/setSpresolution 2.0 mm
/gate/digitizer/Singles/spblurring/verbose 0
/gate/digitizer/Singles/insert thresholder
/gate/digitizer/Singles/thresholder/setThreshold 20. keV
/gate/digitizer/Singles/insert upholder
/gate/digitizer/Singles/upholder/setUphold 190. keV
w/o spblurring with spblurring

10. Source scripting Multiple sources Controlled by source manager
Inserted via scripting
Complex geometries: customized gps
An example: dual isotope scan simulation
F-18 and O-15 in PET
Tc-99m and Tl-201 in SPECT
/gate/source/addSource F18LineSource
/gate/source/F18LineSource/setActivity Bq
/gate/source/F18LineSource/gps/particle e+
/gate/source/F18LineSource/setForcedHalfLife s
/gate/source/F18LineSource/gps/energytype Fluor18
/gate/source/addSource O15LineSource
/gate/source/O15LineSource/setActivity Bq
/gate/source/O15LineSource/gps/particle e+
/gate/source/O15LineSource/setForcedHalfLife s
/gate/source/O15LineSource/gps/energytype Oxygen15

11. Output scripting # O U T P U T /gate/output/ascii/setOutFileHitsFlag 0
/gate/output/ascii/setOutFileSinglesFlag 0
/gate/output/ascii/setOutFileCoincidencesFlag 0
/gate/output/ascii/setOutFiledelayFlag 0
/gate/output/root/enable
/gate/output/root/setFileName benchmarkPET
/gate/output/root/setRootHitFlag 0
/gate/output/root/setRootSinglesFlag 0
/gate/output/root/setRootCoincidencesFlag 1
/gate/output/root/setRootdelayFlag 1

12. Timing scripting Simulation time
A clock models the passing of time during experiments
The user defines the experiment timing
Time-dependent objects
Updated when time changes
Allows programming of movement, tracer kinetics..
/gate/application/setTimeSlice s
/gate/application/setTimeStart s
/gate/application/setTimeStop s
/gate/application/startDAQ

13. How to run GATE Interactive mode Batch mode Parameterized macro
gate
Interactive mode
Batch mode
Parameterized macro
[G4] 
[G4] *************************************************************
[G4]  Geant4 version Name: geant patch-03    (29-January-2010)
[G4]                       Copyright : Geant4 Collaboration
[G4]                       Reference : NIM A 506 (2003),
[G4]                             WWW :
[Core-0] Initialization of geometry
[Core-0] Initialization of physics
[Core-0] Initialization of actors
[Core-0] 
[Core-0] **********************************************************************
[Core-0]  GATE version name: gate_v6.0_p01                                           
[Core-0]                     Copyright : OpenGATE Collaboration                
[Core-0]                     Reference : Phys. Med. Biol. 49 (2004)   
[Core-0]                     WWW :
Idle>
gate benchSPECT.mac
/control/execute vis.mac
GATE 6.0 버젼 에서는 parameterized macro 실행 안됨. Bug!!
6.1. 버젼부터는 fix 되어 실행가능.
Got standard cmap
Window name: viewer-0 (OpenGLStoredX)
/tracking/storeTrajectory 1 …
Idle>

14. 감사합니다. GATE URL : http://www.opengatecollaboration.org
To install GATE:
To use GATE: