• 대한방사선기술학회지:방사선기술과학
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• 제37권2호
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• pp.135-141
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• 2014

개인의 피폭선량 측정에 사용되는 유리선량계 (Glass Dosimeter; GD)와 선량측정용 Piranha 반도체 선량계를 이용하여 진단방사선영역에서 사용하는 저에너지 X-선 영역에서 관전류량을 변화시켜 (5mAs, 10mAs, 16mAs, 20mAs, 25mAs, 32mAs의 저에너지 방사선) 측정하여 선량에 따른 선형성과 재현성, 그리고 지연시간에 따른 재현성을 평가하였다. 방사선량 측정은 다기능 QA 측정기 (RTI Electronic, Sweden)인 Piranha 657의 external detector로 측정하였다. 측정 조건은 80 kVp, SSD 100 cm로 조사영역은 $10cm{\times}10cm$으로 하였으며 유리선량계에 방사선을 조사하였다. 24개의 유리선량계들은 6 개의 그룹 (5mAs, 10mAs, 16mAs, 20mAs, 25mAs, 32mAs)로 나누고 측정을 하였다. 본 연구는 저 에너지 영역에서 관전류를 변화시켜 선형성 및 재현성을 측정한 결과이며, 유리선량계의 선량 특성에서 앞선 연구의 관전압 변화에 따른 특성과 같이 저 에너지 영역에서도 유용할 것으로 사료된다.

• 한국의학물리학회지:의학물리
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• 제24권3호
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• pp.140-144
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• 2013

본 연구에서는 방사선생물 분야에서는 사용하는 세슘-137 조사기에 대한 기준 흡수선량을 측정하고 시료의 방사선량 평가에 활용하기 위하여 유리선량계를 교정하였다. 세슘-137 감마선에 대하여 IAEA TRS-277 프로토콜을 적용하여 정밀하게 물흡수선량을 결정하였다. 기준 흡수선량 측정에는 PTW-TM300013 전리함과 PTW-TM41023 물팬텀을 사용하였으며, 유리선량계는 DoseAce사의 GD-302M 모델을 사용하였다. 교정된 유리선량계의 불확도(1 SD)는 약 2.7%로 평가되며, 본 결과는 연구용 시료의 방사선량 측정에 이용될 예정이다.

• 한국의학물리학회지:의학물리
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• 제31권2호
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• pp.20-28
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• 2020

Purpose: The objective of this study is to perform Postal dosimetry audits for medical linear accelerators in radiation therapy institutions using glass dosimeters and Gafchromic film reading systems and postal dosimetry audit procedures, and to evaluate radiation therapy doses and mechanical accuracy in medical institutions. Methods: Photon output measured and analyzed using a standard phantom for measuring photon output dose using a glass dosimeter for medical linear accelerators. Mechanical accuracy was measured and analyzed using software for film measurement. Results: Measurement and analysis of photon beam output dose using a standard phantom glass dosimeter for photon beam output dose measurement was completed. All tolerance doses were within 5%. Mechanical accuracy measurement and analysis using a standard phantom for verifying the mechanical accuracy of linear accelerator (LINAC) using a Gafchromic film were completed, and all results were shown within tolerances (2 mm or less). Conclusions: In this study, Postal dosimetry audits were performed on the output dose and mechanical accuracy of photon beams (207 beams) for 106 LINACs from 48 institutions. As a result of corrective action and re-execution, it was confirmed that all engines met the acceptable standard within 2 mm in the linear accelerator.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2010년도 춘계 학술발표회 및 심포지엄
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• pp.166-167
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• 2010

• 대한디지털의료영상학회논문지
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• 제11권1호
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• pp.15-20
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• 2009

Far reducing medical radiation exposure and managing patient doses, Entrance surface doses(ESDs) were measured at Diagnostic Radiology Department in ASAN medical center, also we determined and compared with the Diagnostic Reference Level(DRL) of some other countries. ESDs were measured far the most common types of X-ray procedures, such as chest PA, lumbar spine AP, lumbar spine lateral, Pelvis AP, Skull PA. ESDs were measured by Glass dosimeter and Unfors Xi meter. Those were applied collimation center of phantom's entrance skin surface. The results of ESDs were compared Glass dosimeter with Unfors Xi meter. Those were measured within 5% statistical difference. It seemed well agreement at two devices. In most cases ESDs measured far the different types of X ray procedures were found to be lower than the DRL of IAEA, but ESDs on chest PA, lumbar spine AP, lumbar spine lateral, Pelvis AP, Skull PA were proximity ar excesses at DRL of advanced country. Through this study, we need an investigation and improvement at present diagnostic radiology exam system. Also, radiologists make an effort to reduce patient dose and having a technical skill.

• 한국의학물리학회지:의학물리
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• 제23권2호
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• pp.123-126
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• 2012

혈액조사기의 정기적 정도관리를 위하여 일일, 월간 및 년간점검 항목을 개발하였다. 일일점검은 육안으로 기본적 작동을 점검하고, 월간과 년간점검은 자체 제작한 기구(유리선량계 지그)를 사용하여 조사 콘테이너에 대한 선량평가를 수행하도록 하였다. 본 연구에서 도출한 항목들은 임상적 차원에서 실용적이라고 평가한다.

• Radiation Oncology Journal
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• 제36권3호
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• pp.248-253
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• 2018

Radiation protection in the scrotum to reduce the risk of genetic effect in the future is very important. This study aimed to measure the scrotal dose outside the treatment fields by using the radio-photoluminescence glass dosimeter (RPLGD). The characteristics of RPLGD model GD-302M were studied. Scattered dose to scrotum was measured in one liposarcoma case with the prescribed dose of 60 Gy. RPLGDs were placed in three different locations: one RPLGD was positioned at the posterior area which closer to the scrotum, and the other two RPLGDs were placed between the penis and the scrotum. Three RPLGDs were employed in each location. The scattered doses were measured in every fraction during the whole course of treatment. The entire number of 100 RPLGDs showed the uniformity within ±2%. The signal from RPLGD demonstrated linear proportion to the radiation dose (r = 0.999). The relative energy response correction factor was 1.05. The average scrotal dose was 4.1 ± 0.9 cGy per fraction. The results presented a wide range since there was a high uncertainty during RPLGD placement. The total scrotal dose for the whole course of treatment was 101.9 cGy (1.7% of the prescribed dose). The RPLGD model GD-302M could be used to measure scattered dose after applying the relative energy correction factor.

• 대한디지털의료영상학회논문지
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• 제14권2호
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• pp.9-14
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• 2012

Exposed dose of young child should be managed necessarily. Young child is more sensitive than adult of a Radioactivity, especially, and lives longer than adult. Must reduce exposed dose which follows The ALARA(As Low As Reasonably Achievable)rule is recommended by ICRP(International Commission on Radiological Protection)within diagnostic useful range. Therefore, We have to prepare Pediatric DRL(Diagnostic Reference Level) in Korea as soon as possible. Consequently, in this study, wish to estimate organ dose and effective dose using PCXMC Program(a PC-Based Monte Carlo Program), and measure ESD(Entrance surface dose)and organ dose using Glass dosimeter, and then compare with DRL which follows EC(European Commission)and NRPB(National Radiological Protection Board). Using glass dosimeter and PCXMC programs conforming to the International Committee for Radioactivity Prevention(ICRP)-103 tissue weighting factor based on the item before the organs contained in the Chest, Skull, Pelvis, Abdomen in the organ doses and effective dose and dose measurements were evaluated convenience. In a straightforward way to RANDO phantom inserted glass dosimeter(GD352M)by using the hospital pediatric protocol, and in a indirect way was PCXMC the program through a virtual simulation of organ doses and effective dose were calculated. The ESD in Chest PA is 0.076mGy which is slightly higher than the DRL of NRPB(UK) is 0.07mGy, and is lower than the DRL of EC(Europe) which is 0.1mGy. The ESD in Chest Lateral is 0.130mGy which is lower than the DRL of EC(Europe) is 0.2mGy. The ESD in Skull PA is 0.423mGy which is 40 percent lower than the DRL of NRPB(UK) is 1.1mGy and is 28 percent lower than the DRL of EC(Europe) is 1.5mGy. The ESD in Skull Lateral is 0.478mGy which is half than the DRL of NRPB(UK) is 0.8mGy, is 40 percent lower than the DRL of EC(Europe) is 1mGy. The ESD in Pelvis AP is 0.293mGy which is half than the DRL of NRPB(UK) is 0.60mGy, is 30 percent lower than the DRL of EC(Europe)is 0.9mGy. Finally, the ESD in Abdomen AP is 0.223mGy which is half than the DRL of NRPB(UK) is 0.5mGy, and is 20 percent lower than the DRL of EC is 1.0mGy. The six kind of diagnostic radiological examination is generally lower than the DRL of NRPB(UK)and EC(Europe) except for Chest PA. Shouldn't overlook the age, body, other factors. Radiological technician must realize organ dose, effective dose, ESD when examining young child in hospital. That's why young child is more sensitive than adult of a Radioactivity.

• 한국방사선학회논문지
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• 제17권2호
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• pp.243-248
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• 2023

본 연구에서는 청신경초종 질환에서 방사선 수술 시 유리선량계를 이용하여 손상위험장기들의 피폭으로 인해 발생하는 2차 발암률을 분석하고자 한다. 인체 조직 등가 물질의 소아 팬텀을 사용하여, 종양의 체적은 0.506 cm³, 1.008 cm³, 2.032 cm³ 총 3개의 체적으로 설정하였고, 평균 선량은 18.4 ± 3.4 Gy로 방사선수술계획을 수립하였다. 수술 장비의 테이블에 인체 팬텀을 장착시킨 후 유리선량계를 우안, 좌안, 갑상샘, 흉선, 오른쪽 폐, 왼쪽 폐에 위치시켜 각각 피폭선량을 측정하였다. 본 연구에서 가장 큰 종양체적인 2.032 cm³의 청신경초종 질환에서 감마나이프 방사선 수술 시 손상위험장기의 피폭으로 인한 2차 암 발생률을 유리선량계로 측정한 그 결과는 10,000명 당 1.11명의 2차 암이 발생될 수 있는 것으로 계산되었다. 본 연구는 정위적 방사선 수술 시 발생할 수 있는 2차 방사선 피폭선량의 위험성을 연구하여 향후 방사선의 확률적 영향과 관련된 방사선 장해분야에 기초자료로 활용될 것이라 사료된다.

• Journal of the Korean Physical Society
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• 제73권9호
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• pp.1377-1384
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• 2018

Accurate measurement of the absorbed dose and the effective dose is required in dental panoramic radiography involving relatively low energy with a rotational X-ray tube system using long exposures. To determine the effectiveness of measuring the irradiation by using passive dosimetry, we compared the entrance skin doses by using a radiophotoluminescent glass dosimeter (RPL) and an optically stimulated luminescence detector (OSL) in a phantom model consisting of nine and 31 transverse sections. The parameters of the panoramic device were set to 80 kV, 4 mA, and 12 s in the standard program mode. The X-ray spectrum was applied in the same manner as the panoramic dose by using the SpekCalc Software. The results indicated a mass attenuation coefficient of $0.008226cm^2/g$, and an effective energy of 34 keV. The equivalent dose between the RPL and the OSL was calculated based on a product of the absorbed doses. The density of the aluminum attenuators was $2.699g/cm^3$. During the panoramic examination, tissue absorption doses with regard to the RPL were a surface dose of $75.33{\mu}Gy$ and a depth dose of $71.77{\mu}Gy$, those with regard to the OSL were surface dose of $9.2{\mu}Gy$ a depth dose of $70.39{\mu}Gy$ and a mean dose of $74.79{\mu}Gy$. The effective dose based on the International Commission on Radiological Protection Publication 103 tissue weighting factor for the RPL were $0.742{\mu}Sv$, $8.9{\mu}Sv$, $2.96{\mu}Sv$ and those for the OSL were $0.754{\mu}Sv$, $9.05{\mu}Sv$, and $3.018{\mu}Sv$ in the parotid and sublingual glands, orbit, and thyroid gland, respectively. The RPL was more effective than the OSL for measuring the absorbed radiation dose in low-energy systems with a rotational X-ray tube.