Instrumentation techniques for radiation dosimetry by using luminescence spectroscopy techniques (original) (raw)
Related papers
2017
According to Vietnamese Law on Atomic Energy, personal dosimetry (PD) for radiation workers is required periodically in order to fulfil the national legal requirements on occupational radiation dose management. Since the radiation applications have become popular in Vietnamese society, the thermal luminescence dosimeters (TLDs) have been used as passive dosimeters for occupational monitoring in the nation. Together with the quick increase in radiation applications and the number of personnel working in radiation fields, the Optically Stimulated Luminescence Dosimeters (OSLDs) have been first introduced since 2015. This work presents the establishment of PD measuring procedure using OSLDs which are used for measuring photons and betas known as Inlight model 2 OSL (OSLDs-p,e) and for measuring mixed radiations of neutrons, photons and betas known as Inlight LDR model 2 (OSLDs-n,p,e). Such following features of OSLDs are investigated: detection limit, energy response, linearity, reprod...
Review on the characteristics of radiation detectors for dosimetry and imaging
The enormous advances in the understanding of human anatomy, physiology and pathology in recent decades have led to ever-improving methods of disease prevention, diagnosis and treatment. Many of these achievements have been enabled, at least in part, by advances in ionizing radiation detectors. Radiology has been transformed by the implementation of multi-slice CT and digital x-ray imaging systems, with silver halide films now largely obsolete for many applications. Nuclear medicine has benefited from more sensitive, faster and higher-resolution detectors delivering ever-higher SPECT and PET image quality. PET/MR systems have been enabled by the development of gamma ray detectors that can operate in high magnetic fields. These huge advances in imaging have enabled equally impressive steps forward in radiotherapy delivery accuracy, with 4DCT, PET and MRI routinely used in treatment planning and online image guidance provided by cone-beam CT.
Radiation Measurements, 2008
This paper presents the optically stimulated luminescence (OSL) fluence response of carbon-doped aluminum oxide (Al 2 O 3 :C) dosimeters irradiated with heavy charged particles (HCPs) of energies relevant to radiation protection in space. The dosimeters were exposed to seven HCP beams with linear energy transfer in water from 0.223 keV/ m to 431.8 keV/ m, and fluences from 2.9 × 10 3 cm −2 to 2.8 × 10 10 cm −2 . Irradiations with a 90 Sr/ 90 Y beta source were also performed for comparison. The results show that the dosimeters' response to high-energy protons is similar to that for the 90 Sr/ 90 Y beta source. The supralinearity in the dose response curve of dosimeters exposed to the 90 Sr/ 90 Y beta source and high-energy protons can be avoided by appropriate choice of optical filters. For HCPs from He to Fe no supralinearity was observed in the OSL dose response. We interpret the results in the framework of track structure model.
PLOS ONE, 2015
This study was carried out to investigate the suitability of using the optically stimulated luminescence dosimeter (OSLD) in measuring surface dose during radiotherapy. The water equivalent depth (WED) of the OSLD was first determined by comparing the surface dose measured using the OSLD with the percentage depth dose at the buildup region measured using a Markus ionization chamber. Surface doses were measured on a solid water phantom using the OSLD and compared against the Markus ionization chamber and Gafchromic EBT3 film measurements. The effect of incident beam angles on surface dose was also studied. The OSLD was subsequently used to measure surface dose during tangential breast radiotherapy treatments in a phantom study and in the clinical measurement of 10 patients. Surface dose to the treated breast or chest wall, and on the contralateral breast were measured. The WED of the OSLD was found to be at 0.4 mm. For surface dose measurement on a solid water phantom, the Markus ionization chamber measured 15.95% for 6 MV photon beam and 12.64% for 10 MV photon beam followed by EBT3 film (23.79% and 17.14%) and OSLD (37.77% and 25.38%). Surface dose increased with the increase of the incident beam angle. For phantom and patient breast surface dose measurement, the response of the OSLD was higher than EBT3 film. The in-vivo measurements were also compared with the treatment planning system predicted dose. The OSLD measured higher dose values compared to dose at the surface (Hp(0.0)) by a factor of 2.37 for 6 MV and 2.01 for 10 MV photon beams, respectively. The measurement of absorbed dose at the skin depth of 0.4 mm by the OSLD can still be a useful tool to assess radiation effects on the skin dermis layer. This knowledge can be used to prevent and manage potential acute skin reaction and late skin toxicity from radiotherapy treatments.
Medical applications of optically stimulated luminescence dosimeters (OSLDs
Radiation Measurements, 2010
This work presents an overview of the advances in the application of optically stimulated luminescence (OSL) to dosimetry in diagnostic radiology and radiation therapy achieved by the Oklahoma State University group in collaboration with the University of Oklahoma Health Sciences Center and the University of Texas M. D. Anderson Cancer Center. This overview discusses: (a) the development and demonstration of readout protocols for high-precision dosimetry in radiation therapy using high-energy photons and electrons; (b) the determination of dose profiles inside acrylic phantom in computed tomography; and (c) the performance of OSL dosimeters for dosimetry of proton therapeutic beams, including point measurements in air and along pristine and spread-out Bragg peaks. Our results demonstrate the capability of performing high-precision measurements (experimental standard deviation of 0.7%) in radiotherapy and show the possibility of performing one-dimensional dose mapping in X-ray computed tomography and proton beams. In the case of protons, our results show that OSL dosimeters are energy independent for protons with energies above 100 MeV, but a reduction in efficiency is observed at the end of the proton range.
Thermoluminescence is an established method for radiation dosimetry as well as retrospective dosimetry. In spite of its great success, different difficulties are associated with its application. These include anomalous fading, changes in the properties of the sample due to its heating in the readout phase, including a sensitization due to the combined effect of irradiation and heating and non-linear dose dependence observed in some potential dosimetric materials. Another point is that once the sample is heated during the read-out, the TL signal is erased; this is of help for re-use of the sample, but prevents a repeated reading of the measured quantity. The alternative of using optically stimulated luminescence has become very popular in recent years. Here, the ill effects associated with the heating of the sample are avoided. Also, the possibility of reading out the sample several times exists. This can be done by using short pulses of stimulating light, which deplete only a small part of the trapped charge carriers. The present work points out some difficulties that may take place with OSL. These include a possible superlinearity in the dose dependence as well as dose-rate dependence. Also is discussed the difference between pulsed and integral OSL signals.
CONCEPTS AND TRENDS IN MEDICAL RADIATION DOSIMETRY: Proceedings of SSD Summer School
2011
This book presented state-of-the art in solid state dosimetry with application to radiation medicine.  Fundamentals of dosimetry and relevance to radiation therapy, nuclear medicineand radiology followed by physics of operation and design of wide spectra of radiation detectors bubble detectors,  TLD, OSL,  fibre optic, film, RPL, semiconductor detectors, EPR, electronic dosimetry, microdosimetry and nanodosimetry.  Special focus of this book is in quality assurance in radiation therapy and modern radiation dosimetry for ...