Cargando…

An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method

A number of treatment‐planning systems still use conventional correction methods for body inhomogeneities. Most of these methods (power law method, tissue—air ratio (TAR), etc.) consider only on‐axis points, rectangular fields, and inhomogeneous slabs covering the whole irradiating field. A new meth...

Descripción completa

Detalles Bibliográficos
Autores principales: Stathakis, Sotirios, Kappas, Constantin, Theodorou, Kiki, Papanikolaou, Nikos, Rosenwald, Jean‐Claude
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley and Sons Inc. 2006
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5722477/
https://www.ncbi.nlm.nih.gov/pubmed/16518312
http://dx.doi.org/10.1120/jacmp.v7i1.2042
_version_ 1783285019985313792
author Stathakis, Sotirios
Kappas, Constantin
Theodorou, Kiki
Papanikolaou, Nikos
Rosenwald, Jean‐Claude
author_facet Stathakis, Sotirios
Kappas, Constantin
Theodorou, Kiki
Papanikolaou, Nikos
Rosenwald, Jean‐Claude
author_sort Stathakis, Sotirios
collection PubMed
description A number of treatment‐planning systems still use conventional correction methods for body inhomogeneities. Most of these methods (power law method, tissue—air ratio (TAR), etc.) consider only on‐axis points, rectangular fields, and inhomogeneous slabs covering the whole irradiating field. A new method is proposed that overcomes the above limitations. The new method uses the principle of the Clarkson method on sector integration to take into account the position and lateral extent of the inhomogeneity with respect to the point of calculation, as well as the shape of the irradiating field. The field is divided into angular sectors, and each sector is then treated separately for the presence of inhomogeneities using a conventional correction method. Applying this method, we can predict the correction factors for Co‐60 and 6‐MV photon beams for irregular fields that include inhomogeneities of lower or higher densities relative to water. Validation of the predicted corrections factors was made against Monte Carlo calculations for the same geometries. The agreement between the predicted correction factors and the Monte Carlo calculations was within 1.5%. In addition, the new method was able to predict the behavior of the correction factor when the point of calculation was approaching or moving away from the interface between two materials. PACS number(s): 87.53.Bn, 87.53.Wz
format Online
Article
Text
id pubmed-5722477
institution National Center for Biotechnology Information
language English
publishDate 2006
publisher John Wiley and Sons Inc.
record_format MEDLINE/PubMed
spelling pubmed-57224772018-04-02 An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method Stathakis, Sotirios Kappas, Constantin Theodorou, Kiki Papanikolaou, Nikos Rosenwald, Jean‐Claude J Appl Clin Med Phys Radiation Oncology Physics A number of treatment‐planning systems still use conventional correction methods for body inhomogeneities. Most of these methods (power law method, tissue—air ratio (TAR), etc.) consider only on‐axis points, rectangular fields, and inhomogeneous slabs covering the whole irradiating field. A new method is proposed that overcomes the above limitations. The new method uses the principle of the Clarkson method on sector integration to take into account the position and lateral extent of the inhomogeneity with respect to the point of calculation, as well as the shape of the irradiating field. The field is divided into angular sectors, and each sector is then treated separately for the presence of inhomogeneities using a conventional correction method. Applying this method, we can predict the correction factors for Co‐60 and 6‐MV photon beams for irregular fields that include inhomogeneities of lower or higher densities relative to water. Validation of the predicted corrections factors was made against Monte Carlo calculations for the same geometries. The agreement between the predicted correction factors and the Monte Carlo calculations was within 1.5%. In addition, the new method was able to predict the behavior of the correction factor when the point of calculation was approaching or moving away from the interface between two materials. PACS number(s): 87.53.Bn, 87.53.Wz John Wiley and Sons Inc. 2006-02-21 /pmc/articles/PMC5722477/ /pubmed/16518312 http://dx.doi.org/10.1120/jacmp.v7i1.2042 Text en © 2006 The Authors. This is an open access article under the terms of the Creative Commons Attribution (http://creativecommons.org/licenses/by/3.0/) License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Radiation Oncology Physics
Stathakis, Sotirios
Kappas, Constantin
Theodorou, Kiki
Papanikolaou, Nikos
Rosenwald, Jean‐Claude
An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title_full An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title_fullStr An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title_full_unstemmed An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title_short An inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on Clarkson integration and the 3D beam subtraction method
title_sort inhomogeneity correction algorithm for irregular fields of high‐energy photon beams based on clarkson integration and the 3d beam subtraction method
topic Radiation Oncology Physics
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5722477/
https://www.ncbi.nlm.nih.gov/pubmed/16518312
http://dx.doi.org/10.1120/jacmp.v7i1.2042
work_keys_str_mv AT stathakissotirios aninhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT kappasconstantin aninhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT theodoroukiki aninhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT papanikolaounikos aninhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT rosenwaldjeanclaude aninhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT stathakissotirios inhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT kappasconstantin inhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT theodoroukiki inhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT papanikolaounikos inhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod
AT rosenwaldjeanclaude inhomogeneitycorrectionalgorithmforirregularfieldsofhighenergyphotonbeamsbasedonclarksonintegrationandthe3dbeamsubtractionmethod