• Title/Summary/Keyword: effective dose equivalent

Search Result 106, Processing Time 0.028 seconds

Two-Day Fraction Gamma Knife Radiosurgery for Large Brain Metastasis

  • Joo-Hwan Lee;In-Young Kim;Shin Jung;Tae-Young Jung;Kyung-Sub Moon;Yeong-Jin Kim;Sue-Jee Park;Sa-Hoe Lim
    • Journal of Korean Neurosurgical Society
    • /
    • v.67 no.5
    • /
    • pp.560-567
    • /
    • 2024
  • Objective : We investigated how treating large brain metastasis (LBM) using 2-day fraction Gamma Knife radiosurgery (GKRS) affects tumor control and patient survival. A prescription dose of 10.3 Gy was applied for 2 consecutive days, with a biologically effective dose equivalent to a tumor single-fraction dose of 16.05 Gy and a brain single-fraction dose of 15.12 Gy. Methods : Between November 2017 and December 2021, 42 patients (mean age, 68.3 years; range, 50-84 years; male, 29 [69.1%]; female, 13 [30.9%]) with 44 tumors underwent 2-day fraction GKRS to treat large volume brain metastasis. The main cancer types were non-small cell lung cancer (n=16), small cell lung cancer (n=7), colorectal cancer (n=7), breast cancer (n=3), gastric cancer (n=2), and other cancers (n=7). Twenty-one patients (50.0%) had a single LBM, 19 (46.3%) had a single LBM and other metastases, and two had two (4.7%) large brain metastases. At the time of the 2-day fraction GKRS, the tumors had a mean volume of 23.1 mL (range, 12.5-67.4). On each day, radiation was administered at a dose of 10.3 Gy, mainly using a 50% isodose-line. Results : We obtained clinical and magnetic resonance imaging follow-up data for 34 patients (81%) with 35 tumors, who had undergone 2-day fraction GKRS. These patients did not experience acute or late radiation-induced complications during follow-up. The median and mean progression-free survival (PFS) periods were 188 and 194 days, respectively. The local control rates at 6, 9, and 12 months were 77%, 40%, and 34%, respectively. The prognostic factors related to PFS were prior radiotherapy (p=0.019) and lung cancer origin (p=0.041). Other factors such as tumor volumes, each isodose volumes, and peri-GKRS systemic treatment were not significantly related to PFS. The overall survival period of the 44 patients following repeat stereotactic radiosurgery (SRS) ranged from 15-878 days (median, 263±38 days; mean, 174±43 days) after the 2-day fraction GKRS. Eight patients (18.2%) were still alive. Conclusion : Considering the unsatisfactory tumor control, a higher prescription dose should be needed in this procedure as a salvage management. Moreover, in the treatment for LBM with fractionated SRS, using different isodoses and prescription doses at the treatment planning for LBMs should be important. However, this report might be a basic reference with the same fraction number and prescription dose in the treatment for LBMs with frame-based SRS.

Evaluation of an Education Program for Patients with Asthma who use Inhalers (천식 환자를 위한 흡입기 교육 프로그램의 효과)

  • Lee, Jong-Kyung;Yang, Young-Hee
    • Journal of Korean Academy of Nursing
    • /
    • v.40 no.2
    • /
    • pp.202-212
    • /
    • 2010
  • Purpose: This study was done to evaluate the effectiveness of an education program for patients with asthma who use inhalers. Methods: The research design for this study was a non-equivalent control group quasi-experimental study. Participants in this study were 36 patients for the control group, and 43 patients for the experimental group. The experimental group participated in the education program. The control group received the usual care. Data were collected before and 1 month and 2 months after the program finished and were analyzed using the SPSS 12.0 program. Results: The experimental group had significantly higher scores of knowledge of inhalers, and inhalation technique compared to the control group. However, no significant differences were found between two groups for PEFR, asthma instability, and satisfaction with inhalers. Conclusion: According to the results, the education program was effective in improving knowledge of inhalers, and inhalation technique. Therefore, it is recommended that this education program be used in clinical practice as an effective nursing intervention for patients with asthma on inhalers.

BRCA1 and TP53 Gene-Mutations: Family Predisposition and Radioecological Risk of Developing Breast Cancer

  • Apsalikov, Bakytbek;Manambaeva, Zukhra;Ospanov, Erlan;Massabayeva, Meruyert;Zhabagin, Kuantkan;Zhagiparova, Zhanar;Maximov, Vladymir;Voropaeva, Elena;Apsalikov, Kazbek;Belikhina, Tatiana;Abdrahmanov, Ramil;Cherepkova, Elena;Tanatarov, Sayat;Massadykov, Adilzhan;Urazalina, Naylia
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.8
    • /
    • pp.4059-4062
    • /
    • 2016
  • Frequencies of polymorphisms of genes BRCA1 and ТР53 in breast cancer (BC) patients with a BC family history and radiation history were assessed and compared in the Semey region of Kazakhstan. The study included 60 women directly irradiated by the activities of the Semipalatinsk test site with a calculated effective equivalent dose of 500 mSv and their first generation descendants (group BC+Her+Exp); 65 women with family BC and absence of radiological history - the effective equivalent dose due to anthropogenic sources not exceeding 50 mSv (group BC+Her-Exp). The comparison group consisted of 65 women patients with breast cancer without family and radiological history (BC-Her-Exp). The control group comprised 60 women without breast cancer and without family and radiological history (nonBC). We carried out the genotyping of the polymorphisms c.2311T>C, c.4308T>C and 5382insC of the BRCA1 gene and rs1042522 of the ТР53 gene. The frequency of the polymorphism c.2311T>C was significantly higher in patients of the group BC+Her+Exp than in healthy women, and of the polymorphism 5382insC in BC+Her+Exp compared to all other groups. The frequency of the rs1042522 polymorphism of ТР53 was significantly higher in all groups of patients with breast cancer compared with the control group. Differences between groups of women with breast cancer were significant only in BC+Her+Exp vs. BC+Her-Exp. Combinations of polymorphisms of the genes BRCA1 and TP53 predominated in women with a family and radiological history.

Multivariate statistical study on naturally occurring radioactive materials and radiation hazards in lakes around a Chinese petroleum industrial area

  • Yan Shi;Junfeng Zhao;Baiyao Ding;Yue Zhang;Zhigang Li;Mohsen M.M.Ali;Tuya Siqin;Hongtao Zhao;Yongjun Liu;Weiguo Jiang;Peng Wu
    • Nuclear Engineering and Technology
    • /
    • v.56 no.6
    • /
    • pp.2182-2189
    • /
    • 2024
  • The high-purity germanium gamma-ray spectrometer was used to measure the radioisotope in surface water of lakes in a Chinee petroleum industrial area. 92 samples were collected from surface water of three lakes. Activity concentrations of 232Th, 226Ra and 40K in three lakes were measured, distributed in the range of 101.8-209.4, 192.1-224.9 and 335.0-548.9 mBq/L, respectively. Results were all within the limits of WHO and China. Potential environmental and health risks were assessed by calculating some radiation hazard indicators, radium equivalent index, annual effective dose, excess lifetime cancer risk, absorbed dose rate, external hazard index, internal hazard index, annual gonadal dose equivalent, activity utilization index and representative gamma index, which ranged 0.38-0.54 Bq/L, 0.06-0.08 mSv/y, 0.23 × 10-3-0.31 × 10-3, 0.17-0.24 nGy/h, 1.01 × 10-3-1.46 × 10-3, 1.55 × 10-3-2.02 × 10-3, 1.16-1.66 μSv/y, 3.13 × 10-3-4.45 × 10-3 and 2.60 × 10-3-3.77 × 10-3. The results were all at acceptable levels, meaning no impact on human health. The relationship between the electrical conductivity of surface water and the activity concentration of 232Th, 226Ra and 40K was evaluated. The electrical conductivity value was 0.241-0.369 mS/cm, showing a significant correlation coefficient between 226Ra and 40K and electrical conductivity. Multivariate statistical methods were used to determine the relationship between the activity concentrations of 232Th, 226Ra, and 40K, radiation hazard indicators and electrical conductivity.

Internal Dose Assessment of Worker by Radioactive Aerosol Generated During Mechanical Cutting of Radioactive Concrete (원전 방사성 콘크리트 기계적 절단의 방사성 에어로졸에 대한 작업자 내부피폭선량 평가)

  • Park, Jihye;Yang, Wonseok;Chae, Nakkyu;Lee, Minho;Choi, Sungyeol
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.18 no.2
    • /
    • pp.157-167
    • /
    • 2020
  • Removing radioactive concrete is crucial in the decommissioning of nuclear power plants. However, this process generates radioactive aerosols, exposing workers to radiation. Although large amounts of radioactive concrete are generated during decommissioning, studies on the internal exposure of workers to radioactive aerosols generated from the cutting of radioactive concrete are very limited. In this study, therefore, we calculate the internal radiation doses of workers exposed to radioactive aerosols during activities such as drilling and cutting of radioactive concrete, using previous research data. The electrical-mobility-equivalent diameter measured in a previous study was converted to aerodynamic diameter using the Newton-Raphson method. Furthermore, the specific activity of each nuclide in radioactive concrete 10 years after nuclear power plants are shut down was calculated using the ORIGEN code. Eventually, we calculated the committed effective dose for each nuclide using the IMBA software. The maximum effective dose of 152Eu constituted 83.09% of the total dose; moreover, the five highest-ranked elements (152Eu, 154Eu, 60Co, 239Pu, 55Fe) constituted 99.63%. Therefore, we postulate that these major elements could be measured first for rapid radiation exposure management of workers involved in decommissioning of nuclear power plants, even if all radioactive elements in concrete are not considered.

Intravenous PCA for Pain Management in Terminal Cancer Patients during the Last Days of Life (정맥내 통증 자가조절법을 이용한 말기 암환자의 통증조절)

  • Song, Sun-Ok;Yeo, Jung-Eun;Kim, Heung-Dae;Park, Dae-Pal;Koo, Bon-Up;Lee, Byung-Yong;Hur, Nam-Seog;Lee, Kyung-Sook
    • The Korean Journal of Pain
    • /
    • v.9 no.1
    • /
    • pp.75-82
    • /
    • 1996
  • Background: Nerve blocks, including epidural analgesia, can be risky for terminal cancer pain patients in generally poor conditions. We performed this study to evaluate the efficacy of intravenous patient-controlled analgesia(PCA) to treat severe pain of terminally ill cancer patients during the last days of life. Methods: We explained the patient's poor general condition to relatives and received a written consent to administer PCA. The starting dose of opioid for PCA in cancer pain management was based on previous 24-hour dose. Previous 24-hour opioid dose was converted to intramuscular morphine equivalent. The concentration of opioid mixed into Basal Bolus $Infusor^{(R)}$ was controlled to allow for one half of the previous 24-hour equianalgesic dose to infuse continuously. Patients controlled their pain by pushing the PCA module themselves. Patients were observed by pain service team. Some discharged patients were treated at home until death. Results: Forty eight patients received PCA for last two years. The most common reason receiving a PCA was the patient's poor general condition(52.0%). The mean starting dose of PCA was $20.6{\pm}16.2$ mg of morphine. Over eighty percents of the patients were in good or tolerable state of analgesia. Half of the patients expired within one week. The mean duration of PCA was $8.7{\pm}7.0$ days. The problems during PCA were: difficulty in maintaining intravenous routes, early loss of mentality after starting PCA, hypotension and nausea. Conclusion: We concluded that PCA, if correctly, is an effective, relatively safe and readily controllable method of pain management in terminally ill cancer patients during the last days of life. For future considerations, terminal patients may expire at the comfort of their own homes after the resolution of legal problems regarding using opioid in home care.

  • PDF

Verification of the Protective Effect of Functional Shielding Cream for the Prevention of X-ray Low-dose Exposure (X-ray 저선량 피폭방지를 위한 기능성 차폐크림의 방어 효과 검증)

  • Seon-Chil Kim
    • Journal of the Korean Society of Radiology
    • /
    • v.17 no.4
    • /
    • pp.497-506
    • /
    • 2023
  • In the case of radiation workers in medical institutions, radiation exposure is made for patient protection and accurate procedures, so they have a problem of low dose exposure. Low-dose radiation exposure occurs mainly in parts of the body other than the Apron area, and the most frequent place is the skin of the back of the hand. In particular, since the medical personnel's hands require senses and fine movements during the procedure, they are defenseless in the radiation exposure area and are at risk of exposure. It can solve the problem of shielding such as lead gloves, and it is difficult to use by suggesting the activity of the hand during the procedure. To solve this problem, a shielding cream capable of obtaining a functional radiation protection effect was developed and its shielding performance was compared with lead equivalent of 0.1 mmPb. In the process of manufacturing shielding cream, the shielding performance was improved by adding a defoaming process to reduce air holes to increase the density of the cream. Therefore, the shielding cream using barium sulfate as the main material has a lower shielding rate than the lead plate, and in the realm of effective energy, it is 59%, At high effective energy, a difference of about 37% was shown, indicating that there is a functional radiation protection effect. The advantage is that it can be used directly on the skin, and it is considered that it can be used before wearing surgical gloves and has a permanent protective effect.

Enhancing Gamma-Neutron Shielding Effectiveness of Polyvinylidene Fluoride for Potent Applications in Nuclear Industries: A Study on the Impact of Tungsten Carbide, Trioxide, and Disulfide Using EpiXS, Phy-X/PSD, and MCNP5 Code

  • Ayman Abu Ghazal;Rawand Alakash;Zainab Aljumaili;Ahmed El-Sayed;Hamza Abdel-Rahman
    • Journal of Radiation Protection and Research
    • /
    • v.48 no.4
    • /
    • pp.184-196
    • /
    • 2023
  • Background: Radiation protection is crucial in various fields due to the harmful effects of radiation. Shielding is used to reduce radiation exposure, but gamma radiation poses challenges due to its high energy and penetration capabilities. Materials and Methods: This work investigates the radiation shielding properties of polyvinylidene fluoride (PVDF) samples containing different weight fraction of tungsten carbide (WC), tungsten trioxide (WO3), and tungsten disulfide (WS2). Parameters such as the mass attenuation coefficient (MAC), half-value layer (HVL), mean free path (MFP), effective atomic number (Zeff), and macroscopic effective removal cross-section for fast neutrons (ΣR) were calculated using the Phy-X/PSD software. EpiXS simulations were conducted for MAC validation. Results and Discussion: Increasing the weight fraction of the additives resulted in higher MAC values, indicating improved radiation shielding. PVDF-xWC showed the highest percentage increase in MAC values. MFP results indicated that PVDF-0.20WC has the lowest values, suggesting superior shielding properties compared to PVDF-0.20WO3 and PVDF-0.20WS2. PVDF-0.20WC also exhibited the highest Zeff values, while PVDF-0.20WS2 showed a slightly higher increase in Zeff at energies of 0.662 and 1.333 MeV. PVDF-0.20WC has demonstrated the highest ΣR value, indicating effective shielding against fast neutrons, while PVDF-0.20WS2 had the lowest ΣR value. The Monte Carlo N-Particle Transport version 5 (MCNP5) simulations showed that PVDF-xWC attenuates gamma radiation more than pure PVDF, significantly decreasing the dose equivalent rate. Conclusion: Overall, this research provides insights into the radiation shielding properties of PVDF mixtures, with PVDF-xWC showing the most promising results.

Antioxidant Activities of Perilla frutescens Britton Seed Extract and Its Inhibitory Effects against Major Characteristics of Cancer Cells (들깨 추출물의 항산화 활성과 암세포 기본 특성에 대한 억제 효과)

  • Kim, Sinae;Song, Boram;Ju, Jihyeung
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.44 no.2
    • /
    • pp.208-215
    • /
    • 2015
  • The aim of the study was to investigate the antioxidant activities of ethanol extract of perilla seed (PSE) and its inhibitory effects against major characteristics of cancer cells, such as unrestricted growth and activated metastasis in vitro. The total polyphenol and flavonoid levels of PSE were 222.6 mg gallic acid equivalent/100 g and 285.7 mg quercetin equivalent/100 g, respectively. The radical scavenging activity and ferric reducing antioxidant power of PSE at concentration of 87.5 to $350{\mu}g/mL$ were 24~45% and 28~62%, respectively. Treatment of HCT116 colorectal carcinoma cells and H1299 non-small cell lung carcinoma cells with PSE dose-dependently inhibited growth by 18~94% (at concentration range of 87.5 to $350{\mu}g/mL$) and completely abolished colony formation (at concentration of $175{\mu}g/mL$). PSE was also effective in inhibiting migration of H1299 cells (by 30~37% at concentration range of 87.5 to $350{\mu}g/mL$) and adhesion of both HCT116 and H1299 cells (by 14~16% at concentration of $350{\mu}g/mL$). These results indicate that PSE exerts antioxidant and anti-cancer activities in vitro. It needs to be determined whether or not similar effects can be reproduced in vivo.

Comparative Analyses of the Internal Radiation Exposures due to Food Chain Pathway Using FOOD III Code (FOOD III 코드를 이용한 섭식경로 내부피폭 비교해석)

  • Choi, Yong-Ho;Chung, Kyu-Hoi;Kim, Jin-Kyu;Lee, Jeong-Ho
    • Journal of Radiation Protection and Research
    • /
    • v.13 no.2
    • /
    • pp.41-51
    • /
    • 1988
  • In order to develop a food-chain computer code suitable to the environmental conditions of Korea, the FOOD III code was partially modified. The excution results for Korean male-adult were compared to those from the Canadian version of FOOD III to deduce a more realistic approach in dose assessment. The amounts of Mn-54, Co-58, Co-60, I-131 and I-132 released from Kori unit 1 in1984 were used as the source terms for the sample calculation. The maximum atmospheric dispersion factor(X/Q) value on the site boundary was applied. Through the code modification, organ doses decreased by about $20{\sim}70%$ and the effective committed dose equivalent by about 40% to be $7.935{\times}10^{-6}Sv/y$ which is 0.16% of the ICRP limit, $5{\times}10^{-3}Sv/y$.

  • PDF