1 / 11

COMPARISON BETWEEN PLATO ISODOSE DISTRIBUTION OF A 192 IR SOURCE AND THOSE SIMULATED WITH GEANT4 TOOLKIT

COMPARISON BETWEEN PLATO ISODOSE DISTRIBUTION OF A 192 IR SOURCE AND THOSE SIMULATED WITH GEANT4 TOOLKIT. F. Foppiano 1 , S. Agostinelli 1 , S. Garelli 1 , G. Paoli 1 , M. Bevegni 1 , M.G. Pia 2 , P. Franzone 1 , T. Scolaro 1 , L. Andreucci 1

anneke
Download Presentation

COMPARISON BETWEEN PLATO ISODOSE DISTRIBUTION OF A 192 IR SOURCE AND THOSE SIMULATED WITH GEANT4 TOOLKIT

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. COMPARISON BETWEEN PLATO ISODOSE DISTRIBUTION OF A 192IR SOURCE AND THOSE SIMULATED WITH GEANT4 TOOLKIT F. Foppiano1, S. Agostinelli1, S. Garelli1, G. Paoli1, M. Bevegni1, M.G. Pia2, P. Franzone1, T. Scolaro1 , L. Andreucci1 1National Cancer Institute and 2Physics Dept. of Genova foppiano@hp380.ist.unige.it

  2. Brachytherapy facility At the National Cancer Institute of Genova Ir-192 brachytherapy treatments are performed by a High Dose Rate (HDR) Microselectron afterloading unit. For the treatment planning we use Plato BPS, v 1.2.3 software

  3. Monte Carlo for brachytherapy Monte Carlo simulation topics for brachytherapy: • Dose calculation • Computation of dose deposition kernels for treatment planning dose calculation algorithms based on convolution/superposition methods • Separation of primary, first scatter and multiple scatter components for complex dose deposition models • Computation of other model-dependent parameters, e.g. anisotropy function • Accurate computation of dose deposition in high gradient regions (i. e. near sources) • Verification of experimental calibration procedures

  4. GEANT4 Low Energy Electromagnetic Physics down to250 eVfor electrons and photons • based on the LLNL data libraries • shell effects Geant4 Low Energy Electromagnetic package extends the coverage of physics interactions down to~ 1 keVfor hadrons and ions • Bethe-Block above 2 MeV • Ziegler and ICRU parameterisations (with material dependence) • free electron gas model • quantal harmonic oscillator model • charge dependence (Barkas effect) Further extensions are in progress Relevant for medical, space science, astrophysics etc. applications

  5. Geant4 tests: simulation of  Simulated water (attenuation coefficient) versus NIST data with Geant4 Standard electromagnetic package and Low Energy extension

  6. Description of -Selectron 192Ir source • Geant4 allows complete flexible description of the real geometry • 192Ir energy spectrum • currently described as monochromatic at 356 keV • will soon be described by the new GEANT4 RadioactiveDecay class

  7. Simulation of dose deposition in water • The simulated source is positioned in a 30 cm water box • The dose deposition is investigated in the longitudinal plane • Plane is partitioned in 1 million 1mm3 voxels • A minimum of 10 millions photons are generated on the 4 solid angle -Selectron 192Ir source Longitudinal plane partitioned in cells

  8. Results: PDD

  9. Results: Isodoses distribution

  10. Conclusions and future goals • Monte Carlo simulation is useful in brachytherapy both to obtain model-dependent parameters and to verify experimental data • Geant4 offers reliable particle-matter Monte Carlo simulation within a flexible modern object-oriented toolkit • We have used Geant4 to simulate  coefficients and a commercial brachytherapy source with full dose deposition calculation • Geant4 simulated dose deposition has been compared with Plato BPS calculations and has been found to be consistent Future goals • More realistic description of 192Ir source energy spectrum with the new Geant4 RadioactiveDecay class • Simulation of shielded and Leipizig brachytherapy applicators

More Related