• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Master's Dissertation
DOI
https://doi.org/10.11606/D.85.2019.tde-21112019-165533
Document
Author
Full name
Daniel Litvac
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2019
Supervisor
Committee
Caldas, Linda Viola Ehlin (President)
Chubaci, Jose Fernando Diniz
Pinto, Teresa Cristina Nathan Outeiro
Title in Portuguese
Desenvolvimento de um kit postal dosimétrico para calibração de aplicadores clínicos de betaterapia no Brasil
Keywords in Portuguese
aplicadores clínicos
betaterapia
dosimetria
radiação beta
Abstract in Portuguese
O sistema de saúde no Brasil, como um todo, possui déficits em mão de obra e em infraestrutura. A betaterapia é uma das alternativas que o Sistema Único de Saúde e serviços particulares implantam para suprir a demanda. Aplicadores clínicos de 90Sr/90Y são utilizados para tratamentos dermatológicos e oftálmicos, substituindo o uso de aceleradores lineares, porque são de custo mais baixo, mais práticos e possuem 28,8 anos de meia-vida. A calibração e a recalibração periódica destes aplicadores, para verificação da taxa de dose absorvida, são essenciais para garantir a segurança nos tratamentos clínicos. Trabalhos de pesquisas mostram discrepâncias entre a calibração do fabricante e a realizada em laboratórios, podendo ter consequências danosas para os pacientes. Além disso, são poucos os laboratórios de calibração do tipo padrão primário para fontes de radiação beta no mundo. Na América Latina não existem laboratórios de calibração com este perfil. Foi desenvolvido neste trabalho um kit postal dosimétrico que permitiu a recalibração dos aplicadores clínicos utilizados em hospitais, de maneira prática, rápida e com instruções, por meio de seu envio aos proprietários, e depois retornando ao IPEN para posterior avaliação. Para isto, alguns materiais dosimétricos foram caracterizados em feixes padronizados de radiação beta, utilizando as técnicas de termoluminescência e luminescência opticamente estimulada para comparação de resultados da resposta quanto à reprodutibilidade, linearidade, curva dose-resposta e dependência angular, definindo as condições mais adequadas e o grupo de dosímetros para calibração dos aplicadores clínicos.
Title in English
Development of a dosimetric postal kit for calibration of clinical beta therapy applicators in Brazil
Keywords in English
beta radiation
beta therapy
clinical beta therapy applicators
dosimetry
Abstract in English
The Brazilian health system, as a whole, has a lack in manpower and infrastructure. In the radiotherapy area it is not different, the lack of equipment, as linear accelerators, instigates the search for alternatives that may replace this kind of instruments. Beta therapy is one of these alternatives that the Brazilian Unified Health System and private services implement to supply the demand. Clinical applicators with 90Sr/90Y sources are still used for dermatological and ophthalmic treatments, replacing the use of modern technologies in these procedures, because they are of lower cost, more practical, and they present 28.8 years of half-life. Calibration and periodic recalibration of these applicators, to verify the absorbed dose rates, are essential procedures for the quality assurance in clinical treatments. Research studies have shown discrepancies among the manufacturer calibrations and those performed in research laboratories, and this fact may lead to harmful consequences for patients. In addition, there are only a few primary standard calibration laboratories for beta radiation sources in the world. In Latin America there is no such calibration laboratory with this profile. A dosimetric postal kit was developed in this work which allowed the practical, quick and instructed recalibration of clinical applicators used in hospitals by sending them to the owners, and then returning to IPEN for further evaluation. Therefore, to meet the needs, dosimetric insulating materials were characterized in standard beta radiation beams, using a beta secondary standard system and using the technique of thermoluminescence and optically stimulated luminescence to compare respond results regarding reproducibility, linearity, dose-response curve and angular dependence, defining the most appropriate conditions and the dosimeter group for calibration of clinical applicators.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Publishing Date
2019-12-03
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2020. All rights reserved.