1. Imre Geszti Certificated Clinical Radiophysicist Miskolc Hungary
Virtual Simulation in the Radiooncology Department of B-A-Z County Hospital Miskolc
Imre Geszti
Certificated Clinical Radiophysicist
Miskolc
Hungary

2. Short History Early ’60s Superficial Skin Therapy (Chaoul, Dermopan)
1974 Founded of the Department of Radiooncology, Teletherapy (Cs, Co therapy)
1975 Brachytherapy (GUA)
1977 National Therapy Planning Networking System
Transverse sectioning device
1991 PC based therapy planning (van de Geijn)
1994 Theratron 780c, Gammamed 12i (Gammadot TPS for brachytherapy)
2002 Siemens Primus Dual Energy, digital linac machine, Siemens SimView NT conventional Simulator, real 3D CT based TPS (CMS XiO), connection to the hospital CT scanner via the network system
Intracranial Stereotaxia (Brainlab) (ended by „politics”)
2007 Siemens Oncor Impression linac, Siemens Somatom sensation Open CT Simulator (LAP Dorado laser system, Coherence Dosimetris Workstation)
2008 2nd Oncor linac
2014 ? IMRT, IGRT, (VMAT or RapidArc?), SRS, new Brachytarapy equipment, TPS

3. Devices I. Conventional RT Simulator DICOM Image server
Siemens SimView NT (2002)
Image intensifier
DICOM Image server
Every Images are DICOM based

4. Conventional RT Simulator
Digitaly based imaging

5. Devices II. CT Simulator Siemens SOMATOM Sensation Open (2007)
CT with flat table top
LAP Dorado Laser system
Coherence Dosimetrist (Virtual Simulator Software) workstation

6. Siemens Somatom Sensation Open CT simulator, Coherence Dosimetrist ws
LAP Dorado laser system

7. Devices III. For delineation, and verification TPS
Coherence Oncologist
TPS
CMS XiO
Permedics Odyssey

8. Virtual Simulation Older methodology
Presimulation in conventional Simulator
Marking of the center of the region
Processing CT Images
In another department (not the same building)
Sending via network (advanced version)
Sending via CD-, DVD-ROM
3D Therapy Planning system
Contouring
Planning
Processing of DRRs, hardcopy of isocentric plain
Simulation after the planning
Mark the sign of the „Isocenter”
Verification
Film
EPID

9. Virtual Simulation Newer methodology I.
Pre- and postplanning processing in one step
Patient positioning
AP topogram (fix tube position)
Selecting the region
CT Imeges
Possible postprocessing (changing kernels or other processing details slice thickness etc.)
Sending the images

10. Virtual Simulation Newer methodology II.
VSim software
Delineating (Skin, OAR, PTV)
Reference point managment
Other DICOM format images registration (fusion of images) (MRI, Diagnostic CT, PET etc.)
Virtual beam simulation
Room-, Beam eye view
Virtual machine
Without dose calculation

11. Workflow diagram (CT Simulator)
Patient registration
Patient positioning
Defining laser origin
Region selction
CT topogram
Starting position
CT scanning
Image transfer
Image import
Ref. point marking
Ref. Point management
Skin Contouring
Laser, table coordinates
Marking on patient skin
Other details, postprocesses

13. CT-CT fusion
Without contrast
With contrast

14. CT-MR fusion CT MR

15. CT-PET fusion CT
PET

16. More spectacular fusion of PET and CT
Easier to find the correct place of tumor, and involved tissue volume

17. Creation of the virtual beams

18. Therapy planning preprocedure
Plan calculation (3D TPSs)
Parameter changing possibilities (comformalization of MLCs, selecting adequate beam energies, wedges etc.)
Making hardcopies (images of slices, plan parametres)
DRRs (paper based, and digitaly format)
Parametres for R&V (Lantis)

19. Deviations Random error Intended deviation From inadequate positioning
Changes of the patient weight
From device (laser, table, light field etc.)
Intended deviation
Replace the reference point for better dose distribution
For using different centre of treating volumes (whole breast vs. tumor bed)

20. Verification I.
Optivue 500 Flat panels on Oncor Impression linacs (semiconductor based EPID)
Coherence Therapist workstations
Dedicated for both of the Oncor machines
Possibilities of Portal Imaging application
Fusion of digital format Portal or Verificational Image with DRRs
3 directions (lat., long., vert.) eliminate deviations in 1 mm resolution

21. Verification II. DRR with contours Portal Image (6MV X-ray EPID)
Fused Images

22. Verification III. Bony structure based
Bony structure based registration

23. Verification IV. Inplanted marker based
Relative to inplanted markers
Prostate case
More precise if we can use some „Gold markers”
Differencies relative to DRR it needs to adjust

24. Important considerations
Accuracy of patient treatment
Precise lasers,
Table top (roll, tilt)
Rotating
Deflection
Patient fixation
Verification on Linacs
No soft tissue sensitivity (relative to bony structure)
No tissue moving or respiration tracking
So we believe we’ll have IGRT the near future
Human factor. What do they contour, where is the real tumor or tumor bed?

25. Thank you for your attention
Happy birthday for Prof. Matula