감마선을 이용한 Metronidazole이 함유된 Poly(vinyl alcohol) 하이드로겔 제조 및 특성

백재,박종석,정진오,정성인,권희정,안성준,임윤묵 (사)한국방사선산업학회 2016 방사선산업학회지 Vol.10 No.1

Periodontitis is disease of damaged gum tissue that is not removed the plaque ontoteeth. In case that the symptoms of disease get pain worse, it will have to extract tooth because oftumefy or bleeding at gums so treatment of drug was required to periodontitis. In this study, thehydrogel was prepared by including superior viscous, excellent elastic, and biocompatibility ofPoly(vinyl alcohol, PVA) and antimicrobial drug of Metronidazole (MD). The 15 wt% PVA wasdissolved in deionized water and then prepared PVA solution was irradiated using gamma-ray at25 kGy (10 kGy hr-1). In addition, PVA hydrogel was immersed in each 0.1, 0.25 and 0.5 wt% MDsolution using stirrer for 24 hr. The result of the gelation, 0.5 wt% MD loaded PVA hydrogel (76%)was lower than PVA hydrogel (88.2%). The swelling ration of 0.5 wt% MD loaded PVA hydrogel(294.8%) was higher than PVA hydrogel (105.2%). The compressive strength and thermal propertiesof MD loaded PVA hydrogel was gradually lower. The drug release test of 0.5 wt% MD loadedPVA hydrogel (61%) was higher than 0.1 wt% MD loaded PVA hydrogel (12%). Therefore, MDloaded PVA hygrogel may be a promising tool for periodontitis medicine by gamma-ray.

앱타머 활용 해체원전 액체 방사성폐기물 처리 방사선작업종사자피폭량 예측 및 저감 방안 도출

이민혜,차길용,김종현,김동기,김순영 (사)한국방사선산업학회 2022 방사선산업학회지 Vol.16 No.4

National R&D is being conducted to apply aptamer, which is an eco-friendly bio-material thatcan be combined with specific ionic elements, to the treatment of liquid radioactive waste generated fromdecommissioning of nuclear power plant. In this paper, we evaluated the exposure dose rate of a radiationworker and proposed reduction methods of radiation exposure in post-treatment of aptamer saturatedwith ionic elements after treatment of liquid radioactive waste generated from RVI’s underwatercutting. The evaluation used MCNP code and considered two cases of treating liquid radioactive wasteby embedding all element-specific aptamers developed for a particular element in a single columnand treating liquid radioactive waste by separately embedding the aptamers developed for a particularelement in an element-specific column. It was evaluated that if Co, which accounts for more than 99% of aworker’s exposure, is treated separately from other elements during liquid radioactive waste treatment,it can be advantageous in terms of exposure to a worker by reducing the waste’s volume and treatmenttime and that wearing of lead apron can reduce the dose rate by 12%.

방사성 금속폐기물 오염도 측정 및 분류 시스템 구축을 위한 검출기 성능평가

노성진,한기택,임영기 (사)한국방사선산업학회 2021 방사선산업학회지 Vol.15 No.4

The purpose of this study is to evaluate detector characteristics like evaluation ofthe dependence on linearity, accuracy, and directionality by utilizing a gamma-ray standardbenchmark irradiation system which was built to test the radial performance of the LBC(Lanthanum BromoChloride) detector among the main components of the radioactive metalwaste contamination level measurement and classification system that is to be developed in thisstudy. The detector characteristics were evaluated through benchmark irradiation by using 60Co,137Cs, 241Am mounted on a gamma-ray standard irradiation equipment. For linearity, evaluatinglinearity from the 3,000 mm or greater interval was verified to be better than evaluating linearityfor the entire section and R-square value for each source was verified to be 60-Co: 0.999 904,137-Cs: 0.999 923, 241-Am: 0.999 700. For the reproducibility, the average coefficient value foreach source was verified to be 60Co: 943 282.1, 137Cs: 416 943.8, 241Am: 856 398.1, and the relativestandard deviation value for each was verified to be 60Co: 0.10, 137Cs: 0.14, 241Am: 0.09. Finally,for the response of angle, a change in relative responsiveness from 1.057~1.205 in the horizontaldirection was verified. While it was satisfied within a 20% range for most directions, there was a0.5% difference in the - 75° area. Through this result, we aim to contribute to the improvementof safety reliability for nuclear decommissioning by securing a lower bound for detection that issufficiently low by enhancing the measurement efficiency by building a measurement system thatutilizes multiple scintillators for rapid measurement and classification of large volume of metalwaste in the future and by securing easiness of self-disposal by solving the representative sampleproblem through radioactivity homogeneity evaluation.

이중시간 PET/CT 검사에서 갑상선암 감별을 위한 최대표준섭취계수의 경계값 분석

장보석 (사)한국방사선산업학회 2020 방사선산업학회지 Vol.14 No.2

In this study, a statistical prediction model was proposed by adopting the hypothesis of converting the distribution of SUVm of 80 people with normal thyroid, thyroiditis, and thyroid cancer to a probability density function. The mathematical prediction model corresponding to each patient group was set at the 95% confidence interval considering the statistical significance level, and the clinical guidelines for the normal thyroid, thyroiditis, and thyroid cancer patient groups were presented. The SUVm distribution of the normal thyroid shows the narrowest variance (1.48~1.92) around the median SUVm 1.7. Under SUVm 1.48, a normal thyroid can be confirmed. The SUVm distribution of thyroid inflammation is a section (2.16~3.52) centered on the median 2.84, so there is a section overlapped with the area of thyroid cancer, so a delay scan is required. The SUVm distribution of thyroid cancer shows the widest variance from (1.82 to 4.34) in the 95% confidence interval around the median 3.28. Below SUVm 1.82, the probability of being diagnosed with thyroid cancer is less than 5%, and if it exceeds SUVm 3.52, it can be confirmed as thyroid cancer. In the SUVm mixed section, which is difficult to distinguish between false positives and positives, an optimal cut-off value of SUVm 1.82 was suggested to visually discriminate between normal and thyroid cancer patients. Statistically significant when the delay test was determined based on the proposed cut-off value of 1.82 (p<0.05). Therefore, the cutoff values proposed in the dual time point PET/CT exam can help to obtain accurate imaging information about thyroid cancer.

재활치료 환자에서 DXA를 이용한 요추부와 대퇴경부 골밀도 검사의 상관관계

정묘영,지연상,김창복,동경래,류재광,최지원 (사)한국방사선산업학회 2018 방사선산업학회지 Vol.12 No.4

Average life expectancy is getting longer due to medical developments and improvements in living standards. So much so that the elderly have an increased risk of developing osteoporosis. Therefore, it is important to prevent, diagnose, and treat the senile disease at an early stage through a bone density test. Bone density is measured by dual energy X-ray absorption (DXA). In this study, while using DXA, in cases when the measurements for both the lumbar and the femur could not be taken simultaneously, the correlation between both measurements were known, and the measurement of one area was used to make a clinical inference for the value of the other. Measurements were taken using Lunar Prodigy Advance (GE) for 43 participant with clinically significant fractures. Statistical calculations were produced and analysed regarding bone density. In case of T-score, lumbar spine produced a statistical result of -2.112±1.836 and femur neck was -1.716±1.565. In case of Z-score lumbar spine produced a statistical result of -0.151±1.513, and femur neck -0.026±1.283. It is indicated that the pearson correlation coefficient of T-score between lumbar spine and femur neck is high at 0.699, and the pearson correlation coefficient of Z-score is considered relatively high at 0.503. The correlation of bone density between lumbar spine and femur neck is shown to be statistically meaningful in T-score’s p-value at 0.000 and Z-score’s p-value at 0.001. In conclusion, it seems to have clinical usefulness that we can infer the result of one measurement through that of the other part tested, based on the knowledge of the correlation coefficients between lumbar spine and femur neck.

고에너지 엑스선의 선속평탄여과판이 조사야의 축이탈비 선량 변화에 미치는 영향

지연상,동경래,김성길,정묘영,곽종길,김미현 (사)한국방사선산업학회 2019 방사선산업학회지 Vol.13 No.3

In order to evaluate the usefulness of whether or not to use of high energy x-rayFlattening Filter, we analyzed dose by comparing the change of irradiation surface and the off-axissize at the center. From the results of FF (Flattening filter) and FFF (Flattening filter free) of 6 MVenergy, the dose decreased as the distance of FFF from the center plane. FFF also showed low doseto protect normal tissue around the tumor. FFF was higher near the skin surface than FF, and thedose was higher when the irradiation surface was smaller. FFF can be used to treat radiation thatcan focus on optimizing tumor dose and minimizing peripheral dose when irradiated.

고 에너지 선형가속기 Couch의 Gantry 회전조사 방향에 따른선량 변화 연구

지연상,김성길,정묘영,이정훈 (사)한국방사선산업학회 2019 방사선산업학회지 Vol.13 No.4

Couch consisting of carbon and acrylic material was irradiated with Gantry and thedose to the tumor was compared with Min, Max and Mean values. Novails Tx dedicated treatmenttable was irradiated with 6 MV and 10 MV, and the attenuation coefficient of the does accordingto the angle (0°, 140°, 180°) were compared and analyzed when transmitting the table. As a resultof comparing the dose values obtained in this paper, it was confirmed that the dose distribution tothe normal tissues in the carbon material table is narrower than the acrylic material. When theexperiment was conducted with 6 MV and 10 MV on the Novils TX, it was confirmed that the losswas the largest at 140° due to the density of the table. It is considered that the treatment effect willbe better with the correction because the treatment is performed without the correction accordingto the angle when the usual radiation treatment is performed.

특발성 척추측만증 재활환자의 정형물리치료 전후 Cobb’s 각도의 엑스선 영상평가 고찰

정묘영,동경래,지연상,성경정,최성현 (사)한국방사선산업학회 2020 방사선산업학회지 Vol.14 No.1

In this study, healing was performed using the orthopedic therapy and confirmed thecure by using the cure prognosis. This allows us to examine the clinical use of radiation imagingtechniques for scoliosis. The subject of study is greater than 10° with adult males and females. Patient age is 14 to 40 years old. Also, there are 4 men and 6 women. As a result of the analysis ofthe data, it can be seen that the mean is decreased from 5.6° to 14° (43.5%) to Min 3° (12.0%) andthe reduction rate is 26%. In conclusion, diagnostic imaging allows doctors to determine the overallstate of the patient's health by providing objective data to the hospital where clinical imaging cannot be determined solely by the objective of the clinical condition. Therefore, medical rehabilitationis helpful to patients who develop medical treating patients and therapies, and helps patients treatpatients with medical treatment, thereby contributing to the rehabilitation of patients.

Dual Energy CT에서 Monoenergetic 영상을 이용한 금속성 인공음영 (Metal Artifact) 감소기법에 대한 연구

문일봉,동경래,최성관,곽종길,김호성,정운관 (사)한국방사선산업학회 2018 방사선산업학회지 Vol.12 No.2

It is to find optimize quantity of ray that can decrease metal artifact caused by artificial hip joint, etc. when deciphering an image by monochromatic X-ray. To compare change of CT number value and noise value of metal artifact in animal tested image, 4 areas were selected and changed keV to measure CT number and noise value at each keV then CNR (Contrast to Noise Ratio) value is calculated. From computer analysis result, 62 keV is the point where can get the metal artifact minimized image, but this paper figured out that it is possible to get the metal artifact minimized image from 90 keV. Therefore, it is possible to get diagnosable image that minimized metal artifact by reconstruction in condition of 90 keV when having CT scan for patients who had artificial metal substance enthesis such as pedicle screw enthesis and artificial coxaenthesis.

방사능재난 시 작업자 선량평가에 신속 활용 가능한 AI 기반 내부피폭선량평가체계 개발

이장희,유재룡,박민석,김송현 (사)한국방사선산업학회 2021 방사선산업학회지 Vol.15 No.4

An increase of frequencies occurring the internal exposure situations of radiationworkers is concerned due to the environmental change, which are the enlargement of usingradiation sources and the introduction of decommissioning of nuclear power reactor, of nuclearindustries in Korea. This paper aims at developing a system, which can be impossible for thepresent commercial codes, for internal dosimetry based on artificial intelligence capable forrapidly estimating and processing much measurement information into a bundle under theradiological emergency situations. For defining the assesment model using artificial intelligence,an automatic system for generating database for intake scenarios and input values applicable tothe artificial neural network learning has been constructed by applying with the recommendationof ICRP, OIR and IDEAS. The artificial neural networks have been classified with two model, thatis, the case of knowing intake time and unknowing it. And, architectures for these models havebeen constructed for assessing the committed effective dose, and committed effective dose andintake time, respectively. Loss functions for two models have converged and their over-fitting hasnot occurred, and a validity of the system for internal dosimery based on artificial intelligence hasbeen achieved. And, the validity of the program for internal dosimetry has been also performedby using learning results of the artificial neural network. The accuracy of R2 score is to be about0.998 and this system based on artificial intelligency can be then reliable for internal dosimetry.