• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.187-188
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• 2011

저 에너지 방사선검사 시 부득이하게 방사선 노출을 받게 되는 방사선 작업종사자나 환자의 보호자가 위치와 거리에 따른 방사선 피폭 선량의 감소 방안을 알아보고자 한다. Ion chamber mode 2026c, Reader기 20X6-1800을 사용하여 구강내 검사와 구강외 검사의 각각 검사실과 조정실에서의 관전압의 변화, 관전류와 조사시간의 변화, 조사방향의 변화에 따라 선량을 측정하였다. 그 결과 검사실 안에서는 최고선량이 평균 $702.8{\mu}R$으로 측정 되었으며, 조정실 안에서 측정하였을 경우 $20{\mu}R$이하의 낮은 선량을 보였으며, 후방검사보다 측방검사가 낮은 선량으로 나타났다. 방사선검사 시 위치와 거리에 따른 조사선량을 비교 분석하여, 적절한 거리 확보와 조사되는 중심방사선을 기준으로 측방($90{\sim}135^{\circ}$)에 위치함으로써 방사선 방어에 도움을 줄 것이며, 차폐문을 이용하여 방사선 피폭으로부터 감소 효과를 볼 수 있을 것이다.

• Progress in Medical Physics
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• v.18 no.3
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• pp.167-171
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• 2007

In the case of radiotherapy following breast conservation therapy for breast cancer patients, the characteristic of skin dose was investigated in the treatment of intensity modulated radiation therapy (IMRT) for breast cancer patients by comparing and analysing entrance skin dose irradiated during radiotherapy using tangential technique radiotherpy, and IMRT. The calculation dose irradiated to breast skin was compared with TLD measurement dose in treatment planning by performing the two methods of radiotherapy using tangential technique, and IMRT in treatment planning equipment. The skin absorbed dose was measured to pass a nipple by spacing of 1 cm distance from center to edge of body. In the radiotherapy of tangential technique, for the irradiation of 180 cGy to PTV, the calculation dose was ranged from 103.5 cGy to 155.2 cGy, measurement dose was ranged from 107.5 cGy to 156.2 cGy, and skin dose in the center was maximum 1.45 times more irradiated than that in the edge. In the IMRT, for the irradiation of 180 cGy to PTV, the calculation dose was ranged 9.8 cGy at 80.2 cGy, measurement dose was ranged 8.9 cGy at 77.2 cGy, and skin dose in the center was maximum 0.23 times less irradiated than that in the edge. IMRT was more effective for skin radiation risks because radiation dose irradiated to skin in IMRT was much less than that in radiotherapy of tangential field technique.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.465-471
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• 2012

In this study, three dimensional X-ray dose distribution from dental X-ray generator system was measured by ALOKA PDM-117 dosimeter. The X-ray dose distribution will be change with XCP-DS FIT in oral shot, because the distance between X-ray generator and the dosimeter. The X-ray dose change affects on patient exposure and radiograph image quality. Therefore, it is important to obtain relation between the X-ray dose and the distance. The X-ray dose at the central position was decreased with increasing the distance. Furthermore, the dose at the edge of the X-ray flux was increased with increasing the distance. The increased dose affects on the patient radiation exposure. The present results will provide for good dental radiograph image and reducing radiation over-exposure on patient.

• Progress in Medical Physics
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• v.1 no.1
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• pp.31-42
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• 1990

The finding of long lived free radicals produced by ionizing radiation in organic crystals and the quantification of this effect by electron spin resonance(ESR) spactroscopy has proven excellent dosimetric applicability. The tissue equivalent alanine dosimeter also appear appropriate for radiation therapy level dosimetry. The dose measurement was performed in a Rando phantom using high energy photons as produced by high energy medical linear accelerator and cobalt-60 teletherapy unit. The absorbed dose range of the ESR/alanine dosimetry system could be extended down to 0.1 Gy. The response of the alanine dosimeters was determined for photons at different therapeutic dose levels from less than 0.1 Gy to 100 Gy and the depth dose measurements were carried out for photon energies of 1.25MeV, 6 and 10 MV with alanine dosimeters in Rando phantom. Comparisons between ESR/alanine in a Rando phantom and ion chamber in a water phantom were made performing depth dose measurements to examine the agreement of both methods under field conditions.

• Journal of radiological science and technology
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• v.34 no.2
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• pp.157-163
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• 2011

Recently a variety of high technologies for radiation therapy (IMRT, SRS,. 3D-RT, etc.) has been developed. For the cervical and rectal cancer, 3field or 4field radiotherapy have been applied to the patients. In the case of two-dimensional treatment, one of the most typical side-effects is skin burn due to the radiation irradiation. In general the skin dose is evaluated by only a single measurement during the whole treatment period. In this study, however, skin dose was measured in each radiation treatment and the total skin dose was accumulated in a glass dosimeter through all the cases. After simulating the skin dose from treatment planning system, the results were compared with the actual skin doses. The results showed a good agreement between two data sets. Even though there are certain amount of errors caused by the patient movement along the treatment, the difference between actual dose and simulated dose was within the accepted range of error.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.864-870
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• 2014

To propose a basis for the selection of personal dosimeters to measure radiation dose administration of radiation workers as a way to evaluate the usefulness dosimeter. For the dosimetry of the radiation workers 2012, during 1 year, 30 were radiation workers to measure personal dose. By personal exposure is measured cumulative dose, is investigated the performance of the TLD, PLD, OSLD. And comparing the measured value of each dosimeter dose and analyzed. Medical institutions, inspection work and quarterly confirmed the cumulative exposure dose of radiation workers. Using DAP and Ion-Chamber, to measure to compare TLD, PLD, OSLD dosimeter performance. A comparison of the directly through the X-ray dosimeter and The absolute value of the Ion-Chamber, OSLD more similar than in the TLD and PLD showed the dose values so the excellent ability to measure the results. Also in radiation generating area dose of radiation workers is higher than that in OSLD. Consequently, in terms of the individual exposure management OSLD is appropriated and beneficial than others.

• Journal of The Korean Radiological Technologist Association
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• v.29 no.1
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• pp.6-11
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• 2003

목적 : 전신방사선조사(TBI)시 균등한 선량을 조사할 목적으로 사용되는 각 신체부위별 보상체(compensator) 두께의 결정은 열형광선량계(TLD)를 이용하여 표면선량(surface dose)을 측정하고, 심부선량(depth dose)으로 환산하는 방법을 주로 이용한다. 그러나 이와 같은 방법은 골(bone) 조직에 대한 선량감쇠(dose attenuation)의 영향이 고려되지 않아 신체중심부에서의 정확한 심부선량을 알 수가 없다. 이에 본 연구

• The Journal of Korean Society for Radiation Therapy
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• v.7 no.1
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• pp.32-44
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• 1995

I. 제 목 고에너지 X-선 소조사야의 선량분포 및 계측에 관한 연구 II. 연구의 목적 및 중요성 최근 수술이 어려운 뇌종양등에 대한 방사선수술법(Radiosurgery)이 관심의 대상이 되고 있다. 방사선수술법은 크게 나누어 200여개의 Co-60이 장착된 장치(Gamma Knife)를 이용하는 방법과, X-선치료기를 이용하는 방법은 몇개의 보조기구를 설치하면 가능한 매우 경제적인 방법이다. 따라서 Microtron을 이용한 방사선수술의 기초자료확보를 위하여 소조사야에 대한 선량과 선량분포의 측정 및 계산을 실시하였다. III. 연구의 내용 및 범위 Microtron으로부터 조사되는 6MV, 10MV, 21MV X-선의 지름 3cm이하 소조사야에 대한 정확한 선량 및 선량분포 자료를 확보하기 위해, 가. Microtron치료기와 보조장치등에 대한 정밀도 계측 및 평가 나. 보조 Collimator의 적당한 크기와 재료의 선택 및 설계, 제작. 다. 에너지와 조사야 크기 각각에 대한 여러측정장치(Ion chamber, Diode detector, TLD 및 Film등)를 이용한 선량 및 선량분포 측정. 라. 측정값들의 비교, 검토 및 측정된 자료에 의한 선량 및 선량분포의 계산을 수행했다. IV. 연구결과 및 활용에 대한 건의 본 연구에서 얻은 결과는 다음과 같다. 가. Microtron치료기와 보조장치등의 정확도의 허용 오차범위내에서 잘 일치하였다. 나. 보조 collimater adpator는 총 길이 24cm로 하였으며 재질로는 두랄미늄을 사용하였고, 보조 collimator는 low melting alloy를 사용하였으며 소조사야 크기의 정확도는 0.5mm이내에서 매우 잘 일치 하였다. 다. 방사선 수술법의 에너지 선택에 중요한 요소중의 하나인 penumbra는 6MV X-선에서 가장 적게 나타났으며 라. 소조사면에 대한 깊이-선량 백분율곡선은 모든 에너지에서 조사면이 작아질수록 표면으로 이동하는 경향을 보였다. 이상의 결과로부터 방사선 수술을 시행할 경우 수십억원에 이르는 장비의 도입이나 새로운 시설 없이 Microtron에서 조사되는 고에너지 X-선을 이용할 수 있을 것으로 사료된다. 또한 새로 구입한 측정기나 보조 Collimator를 이용하여 소조사야에 대한 선량측정기술을 습득함으로써 일반적인 소조사야의 방사선치료나 회전치료등에 활용할 수 있다.

• Journal of the Korean Society of Radiology
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• v.11 no.5
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• pp.321-328
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• 2017

The purpose of the study is to provide basic data for the management of individual exposure and the monitoring of natural radiation dose using D-Shuttle dosimeter (Chiyoda Technol Corporation, Tokyo, Japan). The dose was calculated using D-Shuttle dosimeter. The dose was 1.346 mSv when exposed for 400 days, the annual dose per year was 1.228 mSv/year and the average dose per hour was $0.014{\mu}Sv/hr$. Domestic individual external dose (1.295 mSv/year = Korea average natural individual external dose) and domestic additional dose per year is -0.0663 mSv/year. D-Shuttle is a personal dosimeter for radiation monitoring. It can be used as a very useful dosimeter for ALARA because of its excellent detection capability of radiation, real-time radiation exposure management, alarm function of radiation work, and efficient and easy to use personal radiation dose management.. Radiation monitoring equipment for radiation workers and local residents can be used for radiation monitoring in hospitals, industry, medical sites, nuclear accident areas and hazardous areas in non-destructive areas.

• 대한방사선치료학회:학술대회논문집
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• 2000.04a
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• pp.6-6
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• 2000