Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.

This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK) and a modified linear accelerator...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Guerda Massillon-J L, Diego Cueva-Prócel, Porfirio Díaz-Aguirre, Miguel Rodríguez-Ponce, Flor Herrera-Martínez
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2013
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/c8270cdf443f4b14916068ad253faa38
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:c8270cdf443f4b14916068ad253faa38
record_format	dspace
spelling	oai:doaj.org-article:c8270cdf443f4b14916068ad253faa382021-11-18T07:46:11ZDosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.1932-620310.1371/journal.pone.0063418https://doaj.org/article/c8270cdf443f4b14916068ad253faa382013-01-01T00:00:00Zhttps://www.ncbi.nlm.nih.gov/pmc/articles/pmid/23671677/pdf/?tool=EBIhttps://doaj.org/toc/1932-6203This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK) and a modified linear accelerator (linac) for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (MD-V2-55), alanine and thermoluminescent (TLD-100) dosimeters and compared with conventional dosimetry systems. Detectors were calibrated in terms of absorbed dose to water in (60)Co gamma-ray and 6 MV x-ray reference (10×10 cm(2)) fields using an ionization chamber calibrated at a standards laboratory. Absorbed dose to water rate computed with MD-V2-55 was higher than that obtained with the others dosimeters, possibly due to a smaller volume averaging effect. Ratio between the dose-rates determined with each dosimeter and those obtained with the film was evaluated for both treatment modalities. For the LGK, the ratio decreased as the dosimeter size increased and remained constant for collimator diameters larger than 8 mm. The same behaviour was observed for the linac and the ratio increased with field size, independent of the dosimeter used. These behaviours could be explained as an averaging volume effect due to dose gradient and lack of electronic equilibrium. Evaluation of the output factors for the LGK collimators indicated that, even when agreement was observed between Monte Carlo simulation and measurements with different dosimeters, this does not warrant that the absorbed dose to water rate in the field was properly known and thus, investigation of the reference dosimetry should be an important issue. These results indicated that alanine dosimeter provides a high degree of accuracy but cannot be used in fields smaller than 20 mm diameter. Gafchromic film can be considered as a suitable methodology for reference dosimetry. TLD dosimeters are not appropriate in fields smaller than 10 mm diameters.Guerda Massillon-J LDiego Cueva-PrócelPorfirio Díaz-AguirreMiguel Rodríguez-PonceFlor Herrera-MartínezPublic Library of Science (PLoS)articleMedicineRScienceQENPLoS ONE, Vol 8, Iss 5, p e63418 (2013)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Guerda Massillon-J L Diego Cueva-Prócel Porfirio Díaz-Aguirre Miguel Rodríguez-Ponce Flor Herrera-Martínez Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
description	This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK) and a modified linear accelerator (linac) for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (MD-V2-55), alanine and thermoluminescent (TLD-100) dosimeters and compared with conventional dosimetry systems. Detectors were calibrated in terms of absorbed dose to water in (60)Co gamma-ray and 6 MV x-ray reference (10×10 cm(2)) fields using an ionization chamber calibrated at a standards laboratory. Absorbed dose to water rate computed with MD-V2-55 was higher than that obtained with the others dosimeters, possibly due to a smaller volume averaging effect. Ratio between the dose-rates determined with each dosimeter and those obtained with the film was evaluated for both treatment modalities. For the LGK, the ratio decreased as the dosimeter size increased and remained constant for collimator diameters larger than 8 mm. The same behaviour was observed for the linac and the ratio increased with field size, independent of the dosimeter used. These behaviours could be explained as an averaging volume effect due to dose gradient and lack of electronic equilibrium. Evaluation of the output factors for the LGK collimators indicated that, even when agreement was observed between Monte Carlo simulation and measurements with different dosimeters, this does not warrant that the absorbed dose to water rate in the field was properly known and thus, investigation of the reference dosimetry should be an important issue. These results indicated that alanine dosimeter provides a high degree of accuracy but cannot be used in fields smaller than 20 mm diameter. Gafchromic film can be considered as a suitable methodology for reference dosimetry. TLD dosimeters are not appropriate in fields smaller than 10 mm diameters.
format	article
author	Guerda Massillon-J L Diego Cueva-Prócel Porfirio Díaz-Aguirre Miguel Rodríguez-Ponce Flor Herrera-Martínez
author_facet	Guerda Massillon-J L Diego Cueva-Prócel Porfirio Díaz-Aguirre Miguel Rodríguez-Ponce Flor Herrera-Martínez
author_sort	Guerda Massillon-J L
title	Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
title_short	Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
title_full	Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
title_fullStr	Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
title_full_unstemmed	Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.
title_sort	dosimetry for small fields in stereotactic radiosurgery using gafchromic md-v2-55 film, tld-100 and alanine dosimeters.
publisher	Public Library of Science (PLoS)
publishDate	2013
url	https://doaj.org/article/c8270cdf443f4b14916068ad253faa38
work_keys_str_mv	AT guerdamassillonjl dosimetryforsmallfieldsinstereotacticradiosurgeryusinggafchromicmdv255filmtld100andalaninedosimeters AT diegocuevaprocel dosimetryforsmallfieldsinstereotacticradiosurgeryusinggafchromicmdv255filmtld100andalaninedosimeters AT porfiriodiazaguirre dosimetryforsmallfieldsinstereotacticradiosurgeryusinggafchromicmdv255filmtld100andalaninedosimeters AT miguelrodriguezponce dosimetryforsmallfieldsinstereotacticradiosurgeryusinggafchromicmdv255filmtld100andalaninedosimeters AT florherreramartinez dosimetryforsmallfieldsinstereotacticradiosurgeryusinggafchromicmdv255filmtld100andalaninedosimeters
_version_	1718423000814977024

Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.

Ejemplares similares