Monte Carlo based verification of a beam model used in a treatment planning system

Forskningsoutput: Kapitel i bok/rapport/Conference proceedingKonferenspaper i proceeding

Abstract

Modern treatment planning systems (TPSs) usually separate the dose modelling into a beam modelling phase, describing the beam exiting the accelerator, followed by a subsequent dose calculation in the patient. The aim of this work is to use the Monte Carlo code system EGSnrc to study the modelling of head scatter as well as the transmission through multi-leaf collimator (MLC) and diaphragms in the beam model used in a commercial TPS (MasterPlan, Nucletron B. V.). An Elekta Precise linear accelerator equipped with an MLC has been modelled in BEAMnrc, based on available information from the vendor regarding the material and geometry of the treatment head. The collimation in the MLC direction consists of leafs which are complemented with a backup diaphragm. The characteristics of the electron beam, i. e., energy and spot size, impinging on the target have been tuned to match measured data. Phase spaces from simulations of the treatment head are used to extract the scatter from, e. g., the flattening filter and the collimating structures. Similar data for the source models used in the TPS are extracted from the treatment planning system, thus a comprehensive analysis is possible. Simulations in a water phantom, with DOSXYZnrc, are also used to study the modelling of the MLC and the diaphragms by the TPS. The results from this study will be helpful to understand the limitations of the model in the TPS and provide knowledge for further improvements of the TPS source modelling.

Detaljer

Författare
Enheter & grupper
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Radiologi och bildbehandling
Originalspråkengelska
Titel på värdpublikationJournal of Physics: Conference Series
FörlagIOP Publishing
Sidor012027
Volym102
StatusPublished - 2008
PublikationskategoriForskning
Peer review utfördJa
EvenemangInternational Workshop on Monte Carlo Techniques in Radiotherapy Delivery and Verification - McGill Univ, Montreal, Kanada
Varaktighet: 2007 maj 292007 jun 1

Publikationsserier

Namn
Volym102
ISSN (tryckt)1742-6596
ISSN (elektroniskt)1742-6588

Konferens

KonferensInternational Workshop on Monte Carlo Techniques in Radiotherapy Delivery and Verification
LandKanada
OrtMcGill Univ, Montreal
Period2007/05/292007/06/01