Project proposal - Update the CERR treatment
planning system pencil beam database
February 23, 2014
Abstract
The calculation of radiation dose from radiotherapy treatment is generally performed with treatment planning systems (TPS) which simplify the
radiation transport problem to gain in calculation efficiency. The Monte
Carlo (MC) method is a powerful tool which allows for highly accurate
estimation of the transport of radiation dose in patients but is computationally expensive. The ability to recalculate the distribution of radiation
dose in a patient with MC methods on the basis of the beams chosen by
the TPS is thus a valuable tool. This project aims at developping the
interface between a TPS and MC software.
1
Background
A treatment planning system (TPS) contains several modules: import of patient geometry from computed tomography images and conversion to radiation
transport data, dose calculation, optimization of beam delivery etc. CERR is a
widely used, open source, MATLAB based TPS partly developped at the TUM
and is available at the Medical Physics Chair of the LMU 1 . Geant4 is a general
purpose Monte Carlo (MC) toolkit developped at CERN used in the calculation
of radiation transport [1]. We have developped an interface between the two
systems allowing the recalculation of the dose distributions predicted by CERR
using Geant4. For this the properties of the beams chosen by the optimization
process in CERR are exported from MATLAB to Geant4. To minimize discrepancies between the dose calculated by CERR and that calculated by Geant4
and to generate treatment plans which match those performed in the clinic, it is
necessary to update the CERR pencil beam database using new data generated
by Geant4 for a realistic treatment beam.
Project
The goal of the project will be to use software provided by the CERR team
of the TUM to update the pencil beam database of CERR, using Geant4 to
create a database which closely matches treatment beams used in the clinic.
The current database contains ideal, mono-energetic pencil beam data which
do not represent the clinical reality.
Techniques/skills
All required expertise is available at the Medical Physics Chair. Chair members
are familiar with MATLAB, CERR, and Geant4. Basic MATLAB and C++
programming will be involved. Basic programming knowledge is required.
Supervision
Overall supervision: Prof. Dr. K. Parodi; katia.parodi@lmu.de
Daily and technical supervision: Guillaume Landry; g.landry@lmu.de
Geant4 support: Dr. Georges Dedes; g.dedes@physik.uni-muenchen.de
CERR support: Dr. Gonzalo Cabal; g.cabal@physik.uni-muenchen.de
1 http://www.cerr.info/about.php
2
Figure 1: The CERR treatment planning system.
3
References
[1] Agostinelli, S. et al., Geant4 - a simulation toolkit. Nucl. Instrum. Methods
A 506, 250-303 (2003).
4