• Title/Summary/Keyword: First-Year Dose

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Individual Doses to the Public after the Fukushima Nuclear Accident

  • Ishikawa, Tetsuo
    • Journal of Radiation Protection and Research
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    • v.45 no.2
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    • pp.53-68
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    • 2020
  • Background: International organizations such as the World Health Organization (WHO) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) reported public exposure doses due to radionuclides released in the Fukushima nuclear accident a few years after the event. However, the reported doses were generally overestimated due to conservative assumptions such as a longer stay in deliberate areas designated for evacuation than the actual stay. After these reports had been published, more realistic dose values were reported by Japanese scientists. Materials and Methods: The present paper reviews those reports, including the most recently published articles; and summarizes estimated effective doses (external and internal) and issues related to their estimation. Results and Discussion: External dose estimation can be categorized as taking two approaches-estimation from ambient dose rate and peoples' behavior patterns-and measurements using personal dosimeters. The former approach was useful for estimating external doses in an early stage after the accident. The first 4-month doses were less than 2 mSv for most (94%) study subjects. Later on, individual doses came to be monitored by personal dosimeter measurements. On the basis of these measurements, the estimated median annual external dose was reported to be < 1 mSv in 2011 for 22 municipalities of Fukushima Prefecture. Internal dose estimation also can be categorized as taking two approaches: estimation from whole-body counting and estimation from monitoring of environmental samples such as radioactivity concentrations in food and drinking water. According to results by the former approach, committed effective dose due to 134Cs and 137Cs could be less than 0.1 mSv for most residents including those from evacuated areas. Conclusion: Realistic doses estimated by Japanese scientists indicated that the doses reported by WHO and UNSCEAR were generally overestimated. Average values for the first-year effective doses for residents in two affected areas (Namie Town and Iitate Village) were not likely to reach 10 mSv, the lower end of the doses estimated by WHO.

Pelvic insufficiency fracture after radiotherapy in patients with cervical cancer in the era of PET/CT

  • Park, Shin-Hyung;Kim, Jae-Chul;Lee, Jeong-Eun;Park, In-Kyu
    • Radiation Oncology Journal
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    • v.29 no.4
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    • pp.269-276
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    • 2011
  • Purpose: To determine the incidence, risk factors, and clinical characteristics of pelvic insufficiency fracture (PIF) in patients with cervical cancer. Materials and Methods: Between July 2004 and August 2009, 235 patients with non-metastatic cervical cancer were treated with definitive chemoradiation or postoperative radiotherapy. Among 235 patients, 117 (49.8%) underwent the first positron emission tomography/computed tomography (PET/CT) within 1 year after radiotherapy. The median radiation dose was 55 Gy (range, 45 to 60 Gy). Medical charts and imaging studies, including PET/CT, magnetic resonance imaging (MRI), CT. bone scintigraphy were reviewed to evaluate the patients with PIF. Results: Among 235 patients, 16 developed PIF. The 5-year detection rate of PIF was 9.5%. The 5-year detection rate of PIF in patients who underwent the first PET/CT within a year was 15.6%. The median time to development of PIF was 12.5 months (range, 5 to 30 months). The sites of fracture included 12 sacroiliac joints, 3 pubic rami, 3 iliac bones, and 1 femoral neck. Eleven of 16 patients having PIF complained of hip pain requiring medications. One patient required hospitalization for pain control. The significant risk factors of PIF were old age, body mass index less than 23, bone mineral density less than -3.5 SD, and the first PET/CT within a year after radiotherapy. Radiation dose and concurrent chemotherapy had no impact on PIF rate. Conclusion: PIFs were not rare after pelvic radiotherapy in cervical cancer patients in the era of PET/CT. Timely diagnosis and management of PIF can improve quality of life in patients with cervical cancer, in addition to reducing unnecessary medical expenses.

Radiation Exposure from Nuclear Power Plants in Korea: 2011-2015

  • Lim, Young Khi
    • Journal of Radiation Protection and Research
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    • v.42 no.4
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    • pp.222-228
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    • 2017
  • Background: On June 18, 2017, Korea's first commercial nuclear reactor, the Kori Nuclear Power Plant No. 1, was permanently suspended, and the capacity of nuclear power generation facilities will be adjusted according to the governments denuclearization policy. In these circumstances, it is necessary to assess the quality of radiation safety management in nuclear power plants in Korea by evaluating the radiation dose associated with them. Materials and Methods: The average annual radiation dose per unit, the annual radiation dose per person, and the annual dose distribution were analyzed using the radiation dose database of nuclear reactors for the last 5 years. The results of our analysis were compared to the specifications of the Nuclear Safety Act and Medical Law in Korea. Results and Discussion: The annual average per unit radiation dose of global major nuclear power generation was 720 man-mSv, while that of Korea's nuclear power plants was 374 manmSv. No workers exceeded 50 mSv per year or 100 mSv in 5 years. The individual radiation dose according to occupational exposure was 0.59 mSv for nuclear workers, 1.77 mSv for non-destructive workers, and 0.8 mSv for diagnostic radiologists. Conclusion: The radiation safety management of nuclear power plants in Korea has achieved the best outcomes worldwide, which is considered to be the result of the as-low-as-reasonably-achievable (ALARA) approach and strict radiation safety management. Moreover, the occupational exposures were also very low.

Radiation Exposure According to Radiation Technologist' Working Departments (방사선 종사자 근무 분야별 피폭에 관한 검토)

  • Yoon, Chul-Ho;Yoon, Seok-Hwan;Choi, Jun-Gu
    • Journal of radiological science and technology
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    • v.31 no.3
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    • pp.217-222
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    • 2008
  • Radiation dose to radiologists working at three hospitals in Seoul was investigated from Jan 1, 2006 to Dec. 31, 2006. The results are as follows. First, radiation dose to radiologists at a cardiac angiography room was measured as 1.41mSv, the highest while radiation dose to radiologists at a department of radiation oncology was measured as 0.64 mSv, the lowest. Second, radiation dose proves to be in direct proportion to the number of X-ray treatment. Third, as for the radiation dose in X-ray treatments, radiologists in cardiac angiography room are exposed to the largest amount of radiation while radiologists in diagnostic radiology department are exposed to the smallest amount of radiation. Last, radiation dose at a cardiac angiography room is the largest and is followed by nuclear medicine, diagnostic radiology, and radiation oncology departments in order. According to ICRP, exposure less than 20mSv per year is highly recommended while radiation dose is allowed as long as it is ranged less than 50mSv per year or 100mSv within a 5-year period. Taking into account the results, radiation exposure does not do any harm to radiologists at any related departments in Korean hospitals because the dose per year is less than 1.60mSv.

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Efficacy Analysis of Simplified Intensity-modulated Radiotherapy with High or Conventional Dose and Concurrent Chemotherapy for Patients with Neck and Upper Thoracic Esophageal Carcinoma

  • Zhu, Wei-Guo;Zhou, Ke;Yu, Chang-Hua;Han, Ji-Hua;Li, Tao;Chen, Xiao-Fei
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.3
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    • pp.803-807
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    • 2012
  • For patients with neck and upper thoracic esophageal carcinoma, it is difficult to control lymph node metastases with conventional dose therapy. In this study, we assessed the feasibility of simplified intensity-modulated radiotherapy (sIMRT) and concurrent chemotherapy for 44 patients and boosted high-dose to metastatic lymph nodes. Three radiation treatment volumes were defined: PGTVnd, with which 68.1Gy was delivered in high dose group (hsIMRT group), and 60Gy in the conventional dose group (csIMRT group); PTV1, featuring 63.9Gy in the hsIMRT group and 60Gy in the csIMRT group; PTV2, with 54Gy given to both groups. The sIMRT plan included 5 equi-angular coplanar beams. All patients received the cisplatin and 5-FU regimen concurrently with radiotherapy. The treatment was completed within six weeks and one case with grade three acute bronchitis was observed in hsIMRT group. For esophageal lesions, 80% complete response (CR) and 20% partial response (PR) rates were found in the hsIMRT group, and 79.2% CR, with 20.8% PR, in the csIMRT group; for lymph node lesions, 75% CR and 25% PR rates were observed in the hsIMRT group, with 45.8% and 37.5% respectively in the csIMRT group (P<0.05). The differences in 1-, 2- and 3-year relapse-free survival rates were all statistically significant (P<0.05). The major toxicity observed in both groups was Grade I~II leucopenia. sIMRT can generate a desirable dose distribution in treatment of neck and upper thoracic esophageal carcinoma with a better short-term efficacy. Boosted high dosing to metastatic lymph nodes can increase the relapse-free survival rate.

Two-Week Combination Chemotherapy with Gemcitabine, High-Dose Folinic Acid and 5 Fluorouracil (GEMFUFOL) as First-Line Treatment of Metastatic Biliary Tract Cancers

  • Unal, Olcun Umit;Oztop, Ilhan;Unek, Ilkay Tugba;Yilmaz, Ahmet Ugur
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.9
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    • pp.5263-5267
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    • 2013
  • Background: The aim of this study was to evaluate the efficacy and tolerability of a gemcitabine, 5-fluorouracil and leucovorin (GEMFUFOL) chemotherapy regimen as first line treatment of metastatic biliary tract cancer. Materials and Methods: All patients received folinic acid $400mg/m^2$ on day 1, 5-fluorouracil bolus $400mg/m^2$ on day 1, IV infusion of 5-fluorouracil $2400mg/m^2$ over 46 hours, and gemcitabine $1250mg/m^2$ on day 1. Results: A total of 29 patients with metastatic biliary tract cancer received GEMFUFOL regimen as the firstline treatment. The mean follow-up was 22.1 months (95%CI, 12.5-31.8). One patient (3.4%) achieved complete response, 5 (17.2%) had partial response, and 4 (13.8%) had stable disease. The median progression-free survival was 3.3 months (95%CI, 2.9-3.7), and the median overall survival was 8.8 months (95%CI, 3.5-14). The 1-year and 2-year survival rates were 58.6% and 30%, respectively. Grade 3 and 4 toxicity included neutropenia in 4 patients (13.7%), thrombocytopenia in 2 (6.8%), anemia2 (6.8%), and alopecia in 1 (3.4%). Two patients (6.8%) developed febrile neutropenia. A dose reduction was achieved in 8 patients (27.6%) while 5 patients had extended-interval dosage (17.2%) for toxicity. Conclusions: The GEMFUFOL chemotherapy regimen was generally efficacious and tolerable as a first-line treatment of metastatic biliary tract cancer.

Risk Factors for Cognitive Impairment in Patient with Parkinson's Disease Treated with Levodopa (레보도파 요법 중인 파킨슨병 환자의 인지장애 위험 인자 연구)

  • Kim, Kyung Sook;Lee, Kyung Eun;Lee, Myung Koo
    • Korean Journal of Clinical Pharmacy
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    • v.28 no.4
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    • pp.285-292
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    • 2018
  • Background: Long-term levodopa therapy relieves the motor dysfunction associated with Parkinson's disease (PD), but has various effects on non-motor symptoms, including cognitive dysfunction, hallucinations, and affective disorders, and can exacerbate certain aspects of dementia-like cognitive dysfunction. Here, we investigated the relationship between levodopa treatment and development of dementia in patients with PD. Methods: This retrospective study analyzed 76 consecutive patients with PD who had taken levodopa between 2011 and 2015. The participants were initially free of dementia and had initial daily levodopa doses of below 600 mg. Patients who did and did not develop comorbid dementia were compared in terms of potential predictor variables, including PD onset age, sex, levodopa doses, and non-dementia comorbidities. Results: Of the 76 patients, 21 (27.6%) developed dementia, which was followed by hallucinations and insomnia. The independent predictors of incident dementia were PD onset age and second-year and third-year average levodopa doses that were higher than the first-year average levodopa dose. Patients who developed dementia had significantly higher average daily levodopa doses and levodopa dose increases over the 6-year treatment period than those who did not develop dementia. In addition, patients with higher levodopa doses were more likely to experience hallucinations. Conclusion: These results suggest that increases in levodopa doses may be associated with a greater risk of cognitive impairment in patients with PD. Therefore, motor and cognitive functions and levodopa dose increases should be evaluated regularly during long-term levodopa therapy in patients with PD.

Seroprevalence of Measles Antibody and its Attributable Factors in Elementary Students of Routine 2-dose Schedule Era with Vaccination Record (예방접종력이 있는 초등학생의 홍역 항체 양성률 및 기여 요인)

  • Lim, Hyun-Sul;Goh, Un-Yeong;Yang, Byung-Guk;Kim, Young-Taek;Lee, Jong-Koo;Bae, Geun-Ryang
    • Journal of Preventive Medicine and Public Health
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    • v.38 no.4
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    • pp.431-436
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    • 2005
  • Objectives : We investigated the seroprevalence of the measles antibody and its at tributable factors for the students who underwent routine 2-dose Schedule Era. Methods : The subjects were 996 students of the national measles seroepidemiologic study in December 2000 who had vaccination records. We conducted a questionnaire survey and we performed serologic testing for the measlesspecific IgG by using an enzyme linked immunosorbent assay. Results : The coverage for the first dose of the MMR vaccination at 12-15 months of age was 95.1% and the coverage for the second dose of MMR at 4-6 years of age was 35.0%. The proportion of subjects undergoing 2-dosesof MMR dec reased as the age of the subjects increased. The seropositive rate of the measles antibody was significantly high in the second dose vaccinees (93.5% in the second dose group, 84.7% in the non-second dose group, p<0.001) and it was 72.0% in the 0-dose group, 85.4% in the 1-dose group and 93.7% in the 2-dose group (p<0.001). Two point eight percent of the subjects had a past history of measles infection. On the multiple logistic regression analysis, the first and second dose (odds ratio, 8.54; 95% CI.=3.05-23.91), the first dose (odds ratio, 3.06; 95% CI.=1.20-7.81) and the outbreak in the year 2000 (odds ratio, 1.89; 95% CI.=1.24-2.88) were the significant factors for the seropositivity. Conclusions : Maintaining high coverage with a 2-dose vaccination program would be the decisive factor to prevent an outbreak of measles and to eliminate measles in Korea.

Hypersensitive Reaction to Praziquantel in a Clonorchiasis Patient

  • Lee, Jung-Min;Lim, Hyun-Sul;Hong, Sung-Tae
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.273-275
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    • 2011
  • Praziquantel is the drug of choice for clonorchiasis. Since clonorchiasis is endemic in most river basins, praziquantel has been widely used for 30 years in Korea. A 54-year-old Korean woman suffered from hypersensitive reactions, such as nausea, dyspnea, rash, and urticaria after taking the first dose of praziquantel to treat clonorchiasis. She ingested one dose again and the same symptoms appeared, and she was treated at a clinic with anti-histamines. She tried one more dose with anti-histamines but found the same symptoms. Later, she was found to pass eggs of Clonorchis sinensis and medicated with flubendazole. The hypersensitive reaction to praziquantel is rare but occurs. This is the 5th case report in the world.

Analysis of Cholangitis Rates with Extended Perioperative Antibiotics and Adjuvant Corticosteroids in Biliary Atresia

  • Goh, Lynette;Phua, Kong Boo;Low, Yee;Chiang, Li Wei;Yong, Chen;Chiou, Fang Kuan
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • v.24 no.4
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    • pp.366-376
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    • 2021
  • Purpose: There is no consensus regarding adjuvant therapies following Kasai portoenterostomy (KP) for biliary atresia (BA). This study aimed to analyze the effect of extended perioperative intravenous antibiotics (PI-Abx) and adjuvant corticosteroid on cholangitis and jaundice clearance rates in the 3 years post-KP in children with BA. Methods: Data of patients who underwent KP between 1999-2018 at a single center were retrospectively analyzed. Group A (1999-2010) received PI-Abx for 5 days, Group B (2010-2012) received PI-Abx for 5 days plus low-dose prednisolone (2 mg/kg), and Group C (2012-2017) received PI-Abx for 14 days plus high-dose prednisolone (5 mg/kg). Results: Fifty-four patients were included with groups A, B, and C comprising 25, 9, and 20 patients, respectively. The number of episodes of cholangitis was 1.0, 1.6, and 1.3 per patient (p=NS) within the first year and 1.8, 2.3, and 1.7 (p=NS) over 3 years in Groups A, B, and C, respectively. The jaundice clearance rate at 6 months was 52%, 78%, and 50% (p=NS), and the 3-year native liver survival (NLS) rate was 76%, 100%, and 80% (p=NS) in Groups A, B, and C, respectively. A near-significant association was observed between the incidence of cholangitis within the first year and decompensated liver cirrhosis/death at 3 years post KP (p=0.09). Persistence of jaundice at 6 months was significantly associated with decompensated cirrhosis/death at 3 years (p<0.001). Conclusion: The extended duration of PI-Abx and adjuvant corticosteroids was not associated with improved rates of cholangitis, jaundice clearance, or NLS in patients with BA.