• Progress in Medical Physics
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• v.26 no.2
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• pp.93-98
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• 2015

The purpose of this study is to see the usefulness of lead apron for critical organs near the breast under examining. For clinical experiment, 30 female volunteers who agreed to their participation in the experiments, were chosen and divided into two groups, 15 in group A and 15 in group B respectively. group A is to see whether each side of breast under mammography affects to other side glandular on the critical organs is same, because it is not allowed to scan the both breast for same person or to scan repeatedly. Group B is to see the effectiveness of lead apron during the mammography of right breast. Glass dosimeters were placed on the thyroid, the contralateral breast, and lower abdomen where near the breast during examining. The average glandular doses on the surface in mammography of the thyroid gland, the contralateral breast, the lower abdomen were 0.0692 mGy, 0.6790 mGy, and 0.0122 mGy, respectively, which was an extremely low level of glandular dose. In group B, as to the thyroid gland, average dose was decreased from 0.0922 mGy to 0.0158 mGy. The average dose of contralateral breast was decreased from 0.8575 mGy to 0.0286 mGy. The average doses of lower abdomen was decrease 0.0150 mGy to 0.0173 mGy. As to the lower abdomen, dose decreased from 0.0150 mGy before the use of an apron down to 0.0173 mGy after the use. As p-value was under 0.05, statistically significant difference was observed between the two groups. Wearing an apron can have the protective effects on the thyroid gland up to 20 times lower than not wearing one. Besides, it is also necessary to protect the other breast during the examination by wearing one.

• Radioisotope journal
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• v.8 no.3
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• pp.32-37
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• 1993

• Journal of the Korean Society of Radiology
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• v.17 no.2
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• pp.243-248
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• 2023

This study aims to analyze the secondary carcinogenesis rate caused by exposure of organs at risk of damage using a glass dosimeter during radiosurgery in vestibular schwannoma disease. Using a pediatric phantom of human tissue equivalent material, the volume of the tumor was set to a total of three volumes: 0.506 cm³, 1.008 cm³, and 2.032 cm³, and a radiosurgery plan was established with an average dose of 18.4 ± 3.4 Gy. After mounting the human body phantom on the table of surgical equipment, glass dosimeters were placed on the right eye, left eye, thyroid gland, thymus, right lung, and left lung to measure the exposure dose, respectively. In this study, the incidence of secondary cancer due to exposure to damaged organs during gamma knife radiosurgery in vestibular schwannoma disease with the largest tumor volume of 2.032 cm³ was measured with a glass dosimeter. This study studies the risk of secondary radiation exposure dose that can occur during stereotactic radiosurgery, and it is considered that it will be used as basic data in the field of radiation damage related to the stochastic effect of radiation in the future.

• Progress in Medical Physics
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• v.23 no.2
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• pp.123-126
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• 2012

For the purpose of quality assurance (QA) of the blood irradiator, QA programs for daily, monthly, and yearly were developed. For daily tests, simple items for basically operating the machine are recommended. For monthly and yearly tests, the measurement of dose to assure the dose delivery system are performed by a dosimetry devices (Glass dosimeter jig) developed in this study. The QA program is practical for clinical environment.

• Journal of Digital Convergence
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• v.10 no.2
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• pp.249-254
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• 2012

Assessing the exposure dose and the obtained image during the abdominal radiography with 128-slice MDCT scanner and 4-slice MDCT scanner which are recently being used in clinics using the body tissue-equivalent phantom and the glass dosimeter, the results were as follows. During the CT test for the abdomen, the absorbed dose was $35.8{\pm}0.46mGy$ in 4-MDCT, and $19.03{\pm}0.25mGy$ in 128-MDCT, which indicated that the radiation dose necessary to obtain the image meaningful to diagnosis was required less by 128-MDCT(P<0.05). As a result of analyzing the image obtained from the abdominal test using MDCT with a 5-point Likert scale, 4-MDCT showed the result of 3.52 points, and 128-MDCT showed the result of 4.01 points, that is, the image quality of 128-MDCT was evaluated high, and there was a statistically significant difference. In the results above, it is considered that 128 slice MDCT scanner will be much used later as it can reduce the radiation exposure, and make us obtain the high quality of image.

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.202-210
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• 2015

The low dose radiation is done for a long period, thus researchers have to know the exact dose distribution for the irradiated mouse. This research has been conducted in order to find out methods in transmitting an exact dose to mouse in a mouse irradiation experiment carried out using $^{137}Cs$ irradiation equipment installed in the DIRAMS (Dongnam Institution of Radiological & Medical Sciences) research center. We developed a single mouse housing cage and shelf with adjustable geometric factors such as distance and angle from collimator. The measurement of irradiated dose showed a maximal 42% difference of absorbed dose from the desired dose in the conventional irradiation system, whereas only 6% difference of the absorbed dose was measured in the self-developed mouse apartment system. In addition, multi mice housing showed much difference of the absorbed dose in between head and body, compared to single mouse housing in the conventional irradiation system. This research may allow further research about biological effect assessment for the low dose irradiation using the self-developed mouse apartment to provide more exact doses which it tries to transmit, and to have more reliability for the biological analysis results.

• 대한방사선방어학회:학술대회논문집
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• 2011.11a
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• pp.286-287
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• 2011

• Progress in Medical Physics
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• v.22 no.4
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• pp.198-205
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• 2011

Gamma irradiator is widely used for cell, animal experiment, irradiation for blood, dose measurement, and education. Biobeam8000 gamma irradiator (STS Steuerungstechnik &. Strahlenschutz GmbH, Braunschweig, Germany, Cs137, 81.4 TBq) that KIRAMS (Korea Institute of Radiological and Medical Science) has is a irradiation device that enables to be used in large-capacity of 7.5 L and extensive area. Cs-137 source moves range of 24 cm back-and-forth in a regular cycle in beaker for uniform irradiation and a beaker that puts a specimen like existing radiation irradiator such as Gammacell3000 rotates $360^{\circ}$ during irradiation. Precise dose information according to the location of radiation source would be needed because of the movement of radiation source, whereas radiation could be uniformly irradiated in comparison with existing gamma irradiator. In this study, dose distribution of the inside beaker located in Biomeam8000 gamma irradiator was measured using glass dosimeter, and dose evaluation and distribution regarding dose linearity and dose reproducibility were implemented based on measurement results. This aims to show guideline for efficient use of irradiator based on measurement result when doing experiment or radiation exposure.

• 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.

• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.469-476
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• 2016

In this study, evaluated absorbed dose of moving target using PLD according to prescribed dose and therapeutic technique. First, result of MCNPX when target was deviated from exposure field was reduced dose in proportion to distance. According to prescribed dose, absorbed dose of 3D CRT was better than IMRT in low dose and IMRT was more better in high dose. Absorbed dose of 3D CRT was highest according to therapeutic technique. Therefore, 3D CRT was technique of irradiated highest dose to moving target. But, considered protective effect of normal tissue and patient condition that therapeutic technique was selected to maximized treatment efficiency.