• Journal of Radiation Protection and Research
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• v.40 no.1
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• pp.46-54
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• 2015

The thermoluminescence (TL) and optically stimulated luminescence (OSL) are commonly used to measure and record the expose of individuals to ionization radiation. Design and performance test results of a newly developed TL and OSL measurement system are presented in this paper. For this purpose, the temperature of the TL material can be controlled precisely in the range of $1{\sim}1.5^{\circ}C$ by using high-frequency (35 kHz) heating system. This high-frequency power supply was made of transformer with ferrite core. For optical stimulation, we have completed an optimal combination of the filters with the arrangement of GG420 filter for filtering the stimulating light source and a UG11 filter at the detecting window (PMT). By using a high luminance blue LED (Luxeon V), sufficient luminous intensity could be obtained for optical stimulation. By using various control boards, the TL/OSL reader device was successfully interfaced with a personal computer. A software based on LabView program (National Instruments, Inc.) was also developed to control the TL/OSL reader system. In this study, a multi-functional TL/OSL dosimeter was developed and the performance testing of the system was carried out to confirm its reliability and reproducibility.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.499-505
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• 2012

The purpose of this study was to find out the difference of radiation dose value through energy, exposure number, fluoroscopy time, the number of days of exposed scatter X-ray when TLD and OSLD is used in diagnostic radiology. The difference of value were measured by relative ratio and interval. Energy makes high relative ratio of TLD($1.81{\pm}0.41$) than OSLD($1.40{\pm}0.26$), exposure number makes high of OSLD($1.40{\pm}0.26$) than TLD($2.10{\pm}0.10$). There are no significant differences between relative ratio of TLD and OSLD in fluoroscopy time and the number of days of exposed scatter X-ray. But interval of relative ratio in the number of days of exposed scatter X-ray was narrowed in less 0.2. That means, the measurement of scatter X-ray could more confident in TLD and OSLD than the measurement of direct ray. In conclusion, we have to recognize the relative ratio of TLD and OSLD could be vary depending on exposed condition of radiation. And in some cases, double test of TLD and OSLD get more creditable results of dose value.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.329-334
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• 2012

For the dosimetry of the radiation workers, film badge, Thermo Luminescent Dosimeter (TLD), and glass dosimeter are being used and recently, there is a growing trend of using Optically Stimulated Luminescence Dosimeter (OSLD) in the world. However, OSLD is only being applied some of the field in Korea and there has been almost no study made related to OSLD. Thus, the accumulated radiation dose of TLD and OSLD that have been most frequently used in the field was compared in the radiation workers of nuclear medicine and their working areasfor 3 months. As a result, the average surface dose showed 0.85 mSv difference with 1.27 mSv for TLD and 2.12 mSv for OSLD while having 0.73 mSv difference for the average depth dose with 1.33 mSv for TLD and 2.06 mSv for OSLD. The surface dose and depth dose of OSLD showed statistically significant result with higher measurement (p<0.05).

• Progress in Medical Physics
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• v.30 no.4
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• pp.150-154
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• 2019

The objective of this study is to monitor the radiation doses delivered to a cardiac implantable electronic device (CIED) by comparing the absorbed doses calculated by a commercial treatment planning system (TPS) to those measured by an in vivo dosimeter. Accurate monitoring of the radiation absorbed by a CIED during radiotherapy is necessary to prevent damage to the device. We conducted this study on three patients, who had the CIED inserted and were to be treated with radiotherapy. Treatment plans were generated using the Eclipse system, with a progressive resolution photon optimizer algorithm and the Acuros XB dose calculation algorithm. Measurements were performed on the patients using optically stimulated luminescence detectors placed on the skin, near the CIED. The results showed that the calculated doses from the TPS were up to 5 times lower than the measured doses. Therefore, it is recommended that in vivo dosimetry be conducted during radiotherapy for CIED patients to prevent damage to the CIED.

• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.2113-2119
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• 2024

This study presents the development and characterization of a prototype TL/OSL reader for the retrospective dose assessment of individuals in radiological emergencies. The reader is portable, semi-automatic, and capable of accurate measurements. The dimension of the reader is 25 × 25 × 37 cm³ and the weight is about 15 kg. The reader consists of a sample moving stage, a heating module, an optical stimulation module, a detection module, a data acquisition (DAQ) unit, a nitrogen gas control module, and a PC with a GUI program. The reader has three measurement modes: TL, CW_OSL, and custom mode. The reader was characterized using commercial thermal luminescence dosimeters (TLD, LiF:Mg,Cu,Si) and optically stimulated dosimeters (OSLD, Al₂O₃:C), as well as fortuitous materials, such as display glasses and resistors of mobile phone. The results showed that the reader is capable of measuring signals with a detection limit of up to 0.02 mGy using a commercial dosimeter. In the dose recovery test using fortuitous materials, the reconstructed doses obtained three days post-irradiation closely aligned with the initially administered doses. As a result, this study suggests that the developed TL/OSL reader is a promising instrument for emergency dose assessment at accident sites.

• The Journal of the Korea Contents Association
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• v.14 no.12
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• pp.845-853
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• 2014

In this study, we measured the dose reaching the OSLD dosimeter by using the regular lead apron, and air gap apron through 3 experiments, and researched the reductive effect of air gap apron on exposure dose based on the 140 keV gamma ray radiating from $^{99m}technetium$, which is the most commonly used in nuclear medicine. As a result, when the gap between the dosimeter and 0.2mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.515 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.138 mSv, which shows reductive effect of dose as much as 0.388 mSv. When the gap between the dosimeter and 0.5mm lead plate is 0 Cm, the average value of 10 dosimeters was 0.296 mSv, and when the gap between the dosimeter and lead plate is 20 Cm, the average value of 10 dosimeters was 0.075 mSv, which shows reductive effect of dose as much as 0.221 mSv. As we check the cumulative dosage for 3 days, the lead apron without air layer shows average 0.239 mSv, and the air gap apron shows 0.176 mSv, which is actually reduced by 0.062 mSv. As we check the cumulative dosage for a month, the lead apron without air layer shows 0.59 mSv, and the air gap apron shows 0.54 mSv, which is reduced by 0.05 mSv.

• Journal of radiological science and technology
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• v.42 no.1
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• pp.47-51
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• 2019

This study was conducted from July 1 to September 30, 2018 using Optically Stimulated Luminescence Dosimeter(OSLD) and photoluminescent glass dosimeter(PLD) to measure the 3-month exposure dose and the cumulative dose in the active working area of the nuclear medicine worker Respectively. As a result, the cumulative dose for three months in the worker and work area was measured as 1.97 mSv and 2.02 mSv in the PLD. The mean surface dose and the mean depth dose of the OSLD were measured to be 2.04 mSv. The difference in the total surface dose measured by the PLD and the OSLD was 0.66mSv and the total mean surface dose was 0.07mSv. The difference between the total depth dose and the total depth dose was 0.1mSv and 0.02mSv, respectively. It was found that the dose value of the OSLD was higher than that of the PLD. In addition, it was found that the maximum difference of 0.01mSv was observed between the PLD and the OSLD of the worker. For the dose measurement of the two dosimetry systems, there was no significant difference between the PLD and the OSLD in the surface dose of 0.239 (p>0.05). Also, the significance of PLD and OSLD in the deep dose was 0.109, which was not statistically significant (p>0.05).

• Journal of the Korean Society of Radiology
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• v.17 no.7
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• pp.1091-1097
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• 2023

Bolus is used in radiation therapy to prescribe an even dose to the tumor when the skin surface is inclined or has irregularities. At this time, the dose to the skin surface increases. Due to the patient's unique body structure and irregular skin, voids may occur between the bolus and the skin, which may reduce the accuracy of treatment. Therefore, in this study, the existing bolus and the self-produced bolus through 3D printing were applied to the nasal area, and the difference between the surface dose after treatment plan and the dose directly measured with an Optically Stimulated luminescence(OSL) dosimeter was compared to the existing bolus. The bolus rate was 97%, PLA 100.33%, ePETELA 75A 100.53%, and ePETELA 85A 100.36%. It was confirmed that there was little error in the measurement values and treatment plan values for each material. In addition, compared to when applying a conventional bolus, a difference of -3% to +0.5% for a 3D printed bolus can be confirmed, so a customized bolus produced through 3D printing can complement the shortcomings of the existing bolus. It is believed that there will be.

• Radiation Oncology Journal
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• v.35 no.2
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• pp.121-128
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• 2017

Purpose: To report the results of a correlation analysis of skin dose assessed by in vivo dosimetry and the incidence of acute toxicity. This is a phase 2 trial evaluating the feasibility of intraoperative radiotherapy (IORT) as a boost for breast cancer patients. Materials and Methods: Eligible patients were treated with IORT of 20 Gy followed by whole breast irradiation (WBI) of 46 Gy. A total of 55 patients with a minimum follow-up of 1 month after WBI were evaluated. Optically stimulated luminescence dosimeter (OSLD) detected radiation dose delivered to the skin during IORT. Acute toxicity was recorded according to the Common Terminology Criteria for Adverse Events v4.0. Clinical parameters were correlated with seroma formation and maximum skin dose. Results: Median follow-up after IORT was 25.9 weeks (range, 12.7 to 50.3 weeks). Prior to WBI, only one patient developed acute toxicity. Following WBI, 30 patients experienced grade 1 skin toxicity and three patients had grade 2 skin toxicity. Skin dose during IORT exceeded 5 Gy in two patients: with grade 2 complications around the surgical scar in one patient who received 8.42 Gy. Breast volume on preoperative images (p = 0.001), ratio of applicator diameter and breast volume (p = 0.002), and distance between skin and tumor (p = 0.003) showed significant correlations with maximum skin dose. Conclusions: IORT as a boost was well-tolerated among Korean women without severe acute complication. In vivo dosimetry with OSLD can help ensure safe delivery of IORT as a boost.

• Journal of the Korean Society of Radiology
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• v.12 no.1
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• pp.79-83
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• 2018

In this paper, we measured and analyzed the dose correction factor, absorbed dose linearity, peak voltage X-ray response, angular dependence. Exposure dose correction factor, absorbed dose linearity, and peak voltage linearity using the medical X-ray generator were all in accordance with IEC-62387-1 (2007). The reference to the dosimetry direction at 0, 30, and 60 degrees relative to baseline radiation exposure was -29% (${\pm}30^{\circ}$) and + 67% (${\pm}60^{\circ}$). The values measured at $30^{\circ}$ were -8% lower than the standard and -18% lower than the standard at $60^{\circ}$. Therefore, the effect of direction should be corrected when using OSL dot dosimeter.