|   | 
Details
   web
Records
Author (up) Oliver-Canamas, L.; Vijande, J.; Candela-Juan, C.; Gimeno-Olmos, J.; Pujades-Claumarchirant, M.C.; Rovira-Escutia, J.J.; Ballester, F.; Perez-Calatayud, J.
Title A User-Friendly System for Mailed Dosimetric Audits of Ir-192 or Co-60 HDR Brachytherapy Sources Type Journal Article
Year 2023 Publication Cancers Abbreviated Journal Cancers
Volume 15 Issue 9 Pages 2484 - 14pp
Keywords high dose rate brachytherapy; dosimetric audit; error detection; phantom
Abstract Nowadays, the options available to perform external dosimetric audits of the high dose rate (HDR) brachytherapy treatment process are limited. In this work, we present a methodology that allows for performing dosimetric audits in this field. A phantom was designed and manufactured for this purpose. The criteria for its design, together with the in-house measurements for its characterization, are presented. The result is a user-friendly system that can be mailed to perform dosimetric audits in HDR brachytherapy on-site for systems using either Iridium-192 (Ir-192) or Cobalt-60 (Co-60) sources. Objectives: The main goal of this work is to design and characterize a user-friendly methodology to perform mailed dosimetric audits in high dose rate (HDR) brachytherapy for systems using either Iridium-192 (Ir-192) or Cobalt-60 (Co-60) sources. Methods: A solid phantom was designed and manufactured with four catheters and a central slot to place one dosimeter. Irradiations with an Elekta MicroSelectron V2 for Ir-192, and with a BEBIG Multisource for Co-60 were performed for its characterization. For the dose measurements, nanoDots, a type of optically stimulated luminescent dosimeters (OSLDs), were characterized. Monte Carlo (MC) simulations were performed to evaluate the scatter conditions of the irradiation set-up and to study differences in the photon spectra of different Ir-192 sources (Microselectron V2, Flexisource, BEBIG Ir2.A85-2 and Varisource VS2000) reaching the dosimeter in the irradiation set-up. Results: MC simulations indicate that the surface material on which the phantom is supported during the irradiations does not affect the absorbed dose in the nanoDot. Generally, differences below 5% were found in the photon spectra reaching the detector when comparing the Microselectron V2, the Flexisource and the BEBIG models. However, differences up to 20% are observed between the V2 and the Varisource VS2000 models. The calibration coefficients and the uncertainty in the dose measurement were evaluated. Conclusions: The system described here is able to perform dosimetric audits in HDR brachytherapy for systems using either Ir-192 or Co-60 sources. No significant differences are observed between the photon spectra reaching the detector for the MicroSelectron V2, the Flexisource and the BEBIG Ir-192 sources. For the Varisource VS2000, a higher uncertainty is considered in the dose measurement to allow for the nanoDot response.
Address [Oliver-Canamas, Laura] Serv Radiofis & Proteccio Radiol, Consorci Hospitalari Prov Castello CHPC, Castellon de La Plana 12002, Spain, Email: laura.oliver.canas@gmail.com
Corporate Author Thesis
Publisher Mdpi Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:000987247100001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 5542
Permanent link to this record
 

 
Author (up) Palomo, R.; Pujades, M.C.; Gimeno-Olmos, J.; Carmona, V.; Lliso, F.; Candela-Juan, C.; Vijande, J.; Ballester, F.; Perez-Calatayud, J.
Title Evaluation of lens absorbed dose with Cone Beam IGRT procedures Type Journal Article
Year 2015 Publication Journal of Radiological Protection Abbreviated Journal J. Radiol. Prot.
Volume 35 Issue 4 Pages N33-N41
Keywords IGRT; CBCT; lens absorbed dose; TLD
Abstract The purpose of this work is to evaluate the absorbed dose to the eye lenses due to the cone beam computed tomography (CBCT) system used to accurately position the patient during head-and-neck image guided procedures. The on-board imaging (OBI) systems (v. 1.5) of Clinac iX and TrueBeam (Varian) accelerators were used to evaluate the imparted dose to the eye lenses and some additional points of the head. All CBCT scans were acquired with the Standard-Dose Head protocol from Varian. Doses were measured using thermoluminescence dosimeters (TLDs) placed in an anthropomorphic phantom. TLDs were calibrated at the beam quality used to reduce their energy dependence. Average dose to the lens due to the OBI systems of the Clinac iX and the TrueBeam were 0.71 +/- 0.07 mGy/CBCT and 0.70 +/- 0.08 mGy/CBCT, respectively. The extra absorbed dose received by the eye lenses due to one CBCT acquisition with the studied protocol is far below the 500 mGy threshold established by ICRP for cataract formation (ICRP 2011 Statement on Tissue Reactions). However, the incremental effect of several CBCT acquisitions during the whole treatment should be taken into account.
Address [Palomo, R.; Gimeno-Olmos, J.; Carmona, V.; Lliso, F.; Candela-Juan, C.; Perez-Calatayud, J.] La Fe Univ, Dept Radiotherapy, Phys Sect, E-46026 Valencia, Spain, Email: mpuclau@gmail.com
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0952-4746 ISBN Medium
Area Expedition Conference
Notes WOS:000366388500002 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 2494
Permanent link to this record
 

 
Author (up) Perez-Calatayud, J.; Ballester, F.; Tedgren, C.; DeWerd, L.A.; Papagiannis, P.; Rivard, M.J.; Siebert, F.A.; Vijande, J.
Title GEC-ESTRO ACROP recommendations on calibration and traceability of HE HDR-PDR photon-emitting brachytherapy sources at the hospital level Type Journal Article
Year 2022 Publication Radiotherapy and Oncology Abbreviated Journal Radiother. Oncol.
Volume 176 Issue Pages 108-117
Keywords Brachytherapy; High energy; Calibration; Dosimetry; HDR-PDR
Abstract The vast majority of radiotherapy departments in Europe using brachytherapy (BT) perform temporary implants of high-or pulsed-dose rate (HDR-PDR) sources with photon energies higher than 50 keV. Such techniques are successfully applied to diverse pathologies and clinical scenarios. These recommen-dations are the result of Working Package 21 (WP-21) initiated within the BRAchytherapy PHYsics Quality Assurance System (BRAPHYQS) GEC-ESTRO working group with a focus on HDR-PDR source cal-ibration. They provide guidance on the calibration of such sources, including practical aspects and issues not specifically accounted for in well-accepted societal recommendations, complementing the BRAPHYQS WP-18 Report dedicated to low energy BT photon emitting sources (seeds). The aim of this report is to provide a European-wide standard in HDR-PDR BT source calibration at the hospital level to maintain high quality patient treatments.
Address [Perez-Calatayud, Jose] La Fe Hosp, Radiotherapy Dept, Valencia, Spain, Email: javier.vijande@uv.es
Corporate Author Thesis
Publisher Elsevier Ireland Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0167-8140 ISBN Medium
Area Expedition Conference
Notes WOS:000880438000006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5466
Permanent link to this record
 

 
Author (up) Piriz, G.H.; Gonzalez-Sprinberg, G.A.; Ballester, F.; Vijande, J.
Title Dosimetry of Large Field Valencia applicators for Cobalt-60-based brachytherapy Type Journal Article
Year 2024 Publication Medical Physics Abbreviated Journal Med. Phys.
Volume 51 Issue Pages 5094-5098
Keywords dosimetry; Monte Carlo; skin brachytherapy; Valencia applicators
Abstract BackgroundNon-melanoma skin cancer is one of the most common types of cancer and one of the main approaches is brachytherapy. For small lesions, the treatment of this cancer with brachytherapy can be done with two commercial applicators, one of these is the Large Field Valencia Applicators (LFVA).PurposeThe aim of this study is to test the capabilities of the LFVA to use clinically 60Co sources instead of the 192Ir ones. This study was designed for the same dwell positions and weights for both sources.MethodsThe Penelope Monte Carlo code was used to evaluate dose distribution in a water phantom when a 60Co source is considered. The LFVA design and the optimized dwell weights reported for the case of 192Ir are maintained with the only exception of the dwell weight of the central position, that was increased. 2D dose distributions, field flatness, symmetry and the leakage dose distribution around the applicator were calculated.ResultsWhen comparing the dose distributions of both sources, field flatness and symmetry remain unchanged. The only evident difference is an increase of the penumbra regions for all depths when using the 60Co source. Regarding leakage, the maximum dose within the air volume surrounding the applicator is in the order of 20% of the prescription dose for the 60Co source, but it decreases to less than 5% at about 1 cm distance.ConclusionsFlatness and symmetry remains unaltered as compared with 192Ir sources, while an increase in leakage has been observed. This proves the feasibility of using the LFVA in a larger range of clinical applications.
Address [Piriz, Gustavo H.; Gonzalez-Sprinberg, Gabriel A.] Univ Republica, Fac Sci, Med Phys Unit, Montevideo, Uruguay, Email: ghpiriz@gmail.com
Corporate Author Thesis
Publisher Wiley Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0094-2405 ISBN Medium
Area Expedition Conference
Notes WOS:001187737100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6011
Permanent link to this record
 

 
Author (up) Pujades, M.C.; Granero, D.; Vijande, J.; Ballester, F.; Perez-Calatayud, J.; Papagiannis, P.; Siebert, F.A.
Title Air-kerma evaluation at the maze entrance of HDR brachytherapy facilities Type Journal Article
Year 2014 Publication Journal of Radiological Protection Abbreviated Journal J. Radiol. Prot.
Volume 34 Issue 4 Pages 741-753
Keywords bunker; shielding; NCRP 151; brachytherapy; Monte Carlo
Abstract In the absence of procedures for evaluating the design of brachytherapy (BT) facilities for radiation protection purposes, the methodology used for external beam radiotherapy facilities is often adapted. The purpose of this study is to adapt the NCRP 151 methodology for estimating the air-kerma rate at the door in BT facilities. Such methodology was checked against Monte Carlo (MC) techniques using the code Geant4. Five different facility designs were studied for Ir-192 and Co-60 HDR applications to account for several different bunker layouts. For the estimation of the lead thickness needed at the door, the use of transmission data for the real spectra at the door instead of the ones emitted by Ir-192 and Co-60 will reduce the lead thickness by a factor of five for Ir-192 and ten for Co-60. This will significantly lighten the door and hence simplify construction and operating requirements for all bunkers. The adaptation proposed in this study to estimate the air-kerma rate at the door depends on the complexity of the maze: it provides good results for bunkers with a maze (i.e. similar to those used for linacs for which the NCRP 151 methodology was developed) but fails for less conventional designs. For those facilities, a specific Monte Carlo study is in order for reasons of safety and cost-effectiveness.
Address [Pujades, M. C.] Natl Ctr Dosimetry CND, Valencia, Spain, Email: mpuclau@gmail.com
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0952-4746 ISBN Medium
Area Expedition Conference
Notes WOS:000345895800005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2031
Permanent link to this record