• Environmental Analysis Health and Toxicology
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• v.11 no.1_2
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• pp.1-10
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• 1996

A decrease in stratospheric ozone probably caused by chloroflurocarbons (CFCs) emissions, has been observed large parts of-the globe. It is generally accepted that if ozone levels in the stratosphere are depleted, greater amounts of shortwave ultraviolet radiationB (UVB) will reach the earth's surface, resulting in increased incidence of nonmelanoma skin cancer. In this study, we evaluated several mathematical models, such as a power and an exponential model, and a geometric model considering the surface area of a human body part and ages for the prediction of Skin cancer incidence caused by exposure to the UVB radiation. These models basically estimated the risk of skin cancer based on those measurements of the local ozone in stratosphere and UVB. Both were measured at a part of Seoul with a Dobson ozone spectrometer and Robertson-Berger UV Biometer for 1995. As a result, we calculated the point estimation applying a biological amplification factor (BAF), UVB radiation and other factors. We used a Monte-Carlo simulation technique with assumption on the distribution of each considered factor. The sensitivity analysis of model by there components conducted using Gaussian sensitivity method. The annual integral of UVB radiation was 2275 MED (minimal erythema dose)/yr. Also, an estimate of the annual amount of UVB reaching the earth's surface at a korea's latitude and altitude was 3328 MED/yr. The values of the radiation amplification factor (RAF) were ranged from 0.9 to 1.5 in Seoul. To give the effective factors required to model the prediction of skin cancer incidence caused by exposure to the UVB radiation in Korea, we studied the pros and cons of above mentioned models with the application of those parameters measured in Seoul, Korea.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.267-275
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• 1995

Radiotherapy and chemotherapy can effectively control cancer but can also cause new second cancers to develop as long-term complications especially in childhood cancer. We experienced two patients with second malignant solid neoplasm who had been treated with radiation and chemotherapy for childhood cancers One female patient with rhabdomyosarcoma of the right popliteal fossa was treated with radiotherapy at total dose of 54Gy Three years and seven months later, osteosarcoma developed in the field of radiation therapy The other male patient with non-Hodgkin's lymphoma of the small bowel was treated with radiotherapy and leiomyosarcoma developed in the field of radiotherapy 18 years later. We reviewed the literature of the second malignant neoplasm in children in respect of risk factors. The risk for a second primary cancer following radiotherapy or chemotherapy emphasizes the need for life long follow-up of patients receiving such treatments, particularly patients treated for childhood cancers.

• Journal of radiological science and technology
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• v.44 no.6
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• pp.615-621
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• 2021

In the medical field, radiation provides information for the diagnosis and treatment of diseases. As the use of radiation increases and the risk of exposure increases, interest in radiation protection is also rapidly increasing. Lead shielding material is mainly used, which has a risk of lead poisoning and absorption into the body. Tungsten mixed filament shielding sheets were fabricated with a size of 70 × 70 mm and a thickness of 1, 2, and 4 mm by using a 3D printer. In the general shooting experiment, the thickness of the shielding sheet is 1 ~ 5mm, the tube voltage is 60, 80, 100, 120 kVp and the tube current is 20, 40 mAs. In general photography, Tungsten showed better shielding rate compared to Brass, Copper, and Lead protective tools under all irradiation conditions, and in particular, Tungsten 5 mm showed 100% shielding rate. The 3D-printed tungsten mixed filament shielding is expected to be used as a new shield that can replace the existing lead protection tools as it shows a better shielding rate than the existing lead protection tools in Radiography.

• Journal of Radiation Protection and Research
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• v.41 no.1
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• pp.57-70
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• 2016

Background: Since the terminology 'radioactive consumer product' is not quite familiar to the public and is often considered as negative and detrimental things, the educational curriculum is essential for establishing reliability of nuclear energy related and for the development of better communication strategy of radiation risk with the public. To provide base data which is valuable for establishing efficient curriculum of education and training about radiation safety, it is necessary to apprehend the different level of awareness of radiation exposures classified by various consumer products. Materials and Methods: On November 2014, a question investigation about asking awareness level of radiation exposure from various consumer products was done for university students who are highly educated. The object students are studied at a four-year-course universities which is located at Daejeon City. Results and Discussion: Although the average awareness level is comparatively low, the awareness of senior students, who major in radiation, nuclear related departments and male students are relatively high. On the other hand, the awareness of freshman, sophomore, junior students, who do not major in radiation, nuclear related departments and female students are relatively low. It is necessary to provide various information to avoid unnecessary concerns and misconceptions about radiation exposure. Conclusion: This paper will be an instrument for efficient establishment of curriculum of education and training related with radiation safety.

• Journal of radiological science and technology
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• v.41 no.3
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• pp.255-260
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• 2018

Most patients and parents and guardians display frequent anxiety due to radiation exposure during outpatient, ward, and pediatric general radiographic examinations. This is a behavior that perceives only the harmfulness of radiation. For the recognition of medical radiation, we conduct surveys on outpatients, inpatients, and pediatric parents and guardians to identify their awareness, and then use the radiation dose promotional materials After providing accurate information on the use of radiation, the outpatient, inpatient, and pediatric parents and guardians were asked to explain the change in awareness. The questionnaire items were classified into five categories: repetitive radiation awareness for diagnosis, awareness of exposure dose, availability of exposure information, awareness of radiation risk, and awareness of health problems caused by radiation. There was a statistically significant difference in the items of recognition result of medical radiation, although there was a slight difference in the individual items in the pre and post-recognition results of providing information about the radiologists of the protector and the outpatient(p<0.05). Therefore, through the installation of these promotional materials, we will improve our awareness of medical radiation safety during general radiography surveillance in the Department of Radiology to provide better quality medical information and medical services, thereby contributing to strengthening the competitiveness of the hospital.

• 대한방사선방어학회:학술대회논문집
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• 2009.11a
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• pp.108-109
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• 2009

• Radiation Oncology Journal
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• v.19 no.4
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• pp.312-318
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• 2001

Purpose : To assess the locoregional recurrence rate, survival rate and prognostic factors after modified radical mastectomy and postoperative adjuvant radiation therapy with or with chemotherapy in high-risk breast cancer patients. Methods : Between $1984\~1995$, 48 patients underwent postoperative irradiation to the regional lymphatics and chest wall due to large tumor size $(\geq5\;cm)$ or small tumor size (<5 cm) with axillary lymph node involvement after modified radical mastectomy. The median age of the patients was 47 years (range, $31\~79\;years$). The clinical tumor size was <2 cm in 1 patient, $2\~5\;cm$ in 15 patients, and >5 cm in 32 patients. Thirty two patients had positive axillary lymph nodes. Forty two patients were irradiated to the chest wall and regional lymph node and 6 patients were irradiated in the chest wall only. Radiation dose to the chest wall and regional lymph node was 5040 cGy/28 fraction. The median follow-up time was 61 months. Results : Locoregional recurrence rate was $8\%$ and distant metastatic rate was $14\%$. The actuarial overall survival rate and disease-free survival rate was $53\%\;and\;62\%$ at 5 years, respectively. The median survival time was 57 months. Five-year overall survival rate by the stage is $70\%$ in IIB and $58\%$ in IIA. The significant prognostic factor for survival on multivariate analysis was the stage. Conclusion : Postoperative adjuvant radiation therapy in high-risk breast cancer can reduce the locoregional recurrence rate and increase the survival time by combined chemotherapy. The significant prognostic factor for survival rate was the stage.

• Journal of Preventive Medicine and Public Health
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• v.43 no.3
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• pp.213-221
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• 2010

Objectives: Plasma lipid profiles and Apolipoprotein E (ApoE) are established risk factors for cardiovascular disease (CVD). The knowledge of lipid profile may estimate the potential victims of cardiovascular disease before its initiation and progression and offers the opportunity for primary prevention. The most common ApoE polymorphism has been found to influence plasma lipid concentrations and its correlation with CVD has been extensively investigated in the last decade. Methods: The ApoE polymorphism and its influence on plasma lipid were investigated in healthy woman workers. The information on confounding factors was obtained through a self-administered questionnaire and ApoE polymorphism was investigated using PCR. Results: The relative frequencies of alleles E2, E3 and E4 for the study population (n = 305) were 0.127, 0.750 and 0.121, respectively. ApoE polymorphism was associated with variations in plasma HDL-cholesterol lipid profile. In order to estimate the independent effects of alleles E2 and E4, as compared with E3, on lipid profile, multiple regression was performed after adjustment for confounding variables such as age, BMI, blood pressure, education status, insulin, fasting glucose, HOMA-IR, menopause. ApoE2 had a negative association with HDL cholesterol and ApoE4 had a positive association with LDL cholesterol. Conclusions: This study identified that the ApoE and CVD risk factors contribute to the lipid profiles, similar to other studies. The analysis including dietary intake and other gene in further studies may help to identify clear effects on lipid profiles as risk factor for CVD.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.5-8
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• 2010

Opened a court in February 10, 2006, a rule of safety management of the diagnosis radiation system was promulgated for safety of the radiation worker, patients and patients' family members. The purpose of this rule is to minimize the risk of being exposed to radiation during the process of handling X-ray. For this reason, we manufactured shielding device of mobile X-ray unit collimator for diminution of skin dose. Shielding device is made to a thickness of Pb 0.375mm. For portable chest radiography, we measured skin dose 50cm from center ray to 200cm at intervals of 20cm by Unfors Xi detector. As a result, a rule of safety management of the diagnosis radiation system has been strengthened. But there are exceptions, such as ER, OR, ICU to this rule. So shielding device could contribute to protect unnecessary radiation exposure and improve nation's health.

• Journal of Radiation Protection and Research
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• v.46 no.4
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• pp.151-159
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• 2021

Background: Computed tomography (CT) is one of the crucial diagnostic tools in modern medicine. However, careful monitoring of radiation dose for CT patients is essential since the procedure involves ionizing radiation, a known carcinogen. Materials and Methods: The most desirable CT dose descriptor for risk analysis is the organ absorbed dose. A variety of CT organ dose calculators currently available were reviewed in this article. Results and Discussion: Key common elements included in CT dose calculators were discussed and compared, such as computational human phantoms, CT scanner models, organ dose database, effective dose calculation methods, tube current modulation modeling, and user interface platforms. Conclusion: It is envisioned that more research needs to be conducted to more accurately map CT coverage on computational human phantoms, to automatically segment organs and tissues for patient-specific dose calculations, and to accurately estimate radiation dose in the cone beam computed tomography process during image-guided radiation therapy.