1. Modeling and Visualization Hajime Yoshida Naruto UE
Interfacing G4 physics and planning systems
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

2. First Japan-Italy Workshop of Medical Applications of Geant4
Modeling; Geometry
Construct G4 geometry
DICOM driver (local file or network)
Montreal example or further abstraction is necessary?
Voxels of CT images or other modalities are associated with those of Geant4
Voxels are parameterized by their position and density
Sensitive volume is defined for each voxel
Study the possibility of polygons
Polygon construction from voxels by a commercial s/w
Next examples are taken from the Web pages of Kubota Graphics Tec. Co.
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

3. Colon for the virtual endoscope
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

4. Femoral artery and poumonary
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

5. First Japan-Italy Workshop of Medical Applications of Geant4
Visualization
Use of Geant4 Visualization
Visualization of parameterized volumes is implemented in G4 but we have to study what kind of tuning or refinements might be necessary for realistic cases
Use of the commercial products for further functionalities
Volume rendering
Polygon construction from CT images
Smoothing neighboring voxels
Defining boundaries and polygons
Compressing the number of polygons
Relation with 3D stereo-vision
Parallelization
Overlapping with dose histograms
Easy-to-use human interface (3D)
Interface to HIMAC’s visualization system used for the planning system
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

6. First Japan-Italy Workshop of Medical Applications of Geant4
Analysis
Dose Histograms
Voxel based
CT voxel density and dose per each voxel
Volume based
Comparison and overlap　relative to volumes
Evaluation function?
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

7. Toolkits for medical applications
Plan to Customize existing tools; MOMO
Geometry creation
Phantoms, various filters, bolus etc.
Modeling from DICOM data over the network
XML format
Electromagnetic physics
Tuned Standard and LE physics
On-going integration with analysis tools JAS3
Plug-ins to JAS3; MomoPlugin and G4Plugin
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4

8. First Japan-Italy Workshop of Medical Applications of Geant4
Examples
Material and geometry description
XML a la GDML
Eye phantom made yesterday morning
2000 water disks of 20 μm thickness
Simplistic Physics list
Just like exampleN02
Proton; hIonisation + multiple scattering
No sensitive volume, just to visualize
WIN32-VC7 (Visual C++ .NET)
OGLWIN32 OpenGL viewer for Windows
Run with GAG with Log window
JAS3 plugins
4/17/2019
First Japan-Italy Workshop of Medical Applications of Geant4