• 대한디지털의료영상학회논문지
• /
• 제13권1호
• /
• pp.1-6
• /
• 2011

The purpose of our study was to determine the entrance surface dose and absorbed dose in ovary when using the metal speculum and plastic speculum in hysterosalpingography respectively. The examinations was performed in anthropomorphic phantom into which calibrated photoluminescence glass dosimeter were placed on symphysis pubis level surface and ovary area. We checked average fluoroscopy time and spot expose times during the hysterosalpingography. It was average fluoroscopy time 58 sec, spot expose 5 times. We divided the subjects into two different groups to used metal and plastic speculum. We measured 10 times of absorbed dose in the same condition of the anthropomorphic phantom. We compared two groups adsorbed dose on ovary with speculum material-related. The entrance surface dose on of plastic Speculum using group was average 17.23 mGy, absorbed dose on ovary was average 3.51 mGy. The entrance surface dose on ovary of metal Speculum using group was average 19.95 mGy, absorbed dose on ovary was average 4.14 mGy. Plastic speculum using group shows a decrease absorbed dose(17.9%) as compared with metal speculum using group. The method of plastic speculum using in hysterosalpingography. might provide us with lower radiation dose, especially in patients with childbearing stage.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.319-321
• /
• 2004

The average glandular dose (AGD) is determined by the breast entrance skin exposure, x-ray tube target material, beam quality (half-value layer), breast thickness, and breast composition. Almost breast cancer always arises in glandular breast tissue. As a result, the average radiation absorbed dose to glandular tissue is the preferred measure of the radiation risk associated with mammography. If the normalized average glandular dose is known, the average glandular dose can be computed from the product of the normalized average glandular dose and breast entrance skin exposure. In this study, AGD was calculated by the breast thickness and various x-ray energy (HVL) in 50% glandular 50% adipose breast by Mo.-Rh. assembly. AGD is 84 mrad in compressed 5 cm breast. These results show that as increasing the breast thickness, dose also increases. But as increasing the x-ray tube voltage, dose decreases because of high penetrating ratio through the object. But high tube voltage is reducing the subject contrast. From this result, we have to consider the trade-off between subject contrast of image and dose to the patient and choose proper x-ray energy range.

• 대한디지털의료영상학회논문지
• /
• 제15권2호
• /
• pp.19-23
• /
• 2013

Purpose : Automatic exposure system(AOP mode) in DR Mammography of the STD and DOSE apply to women of childbearing age, the average glandular dose(AGD) and image quality by comparing was to demonstrate the usefulness of DOSE. Materials and Methods : Of the under 40 age 108 patients who visit to our hospital and examined STD and DOSE mammography from January 2008 to July 2013. AGD was obtained by DICOM header information provided by GE Senographe DS. STD and DOSE images were evaluated with obtained patients, Image J program was compared by calculating the SNR. Results : The average AGD of DOSE mode was 0.99mGy, and which decreased by 19% comparing to that of STD mode which was 1.18mGy. The two the average AGDs indicated statistically significant difference(p< .01). The average SNR of STD was 40.26, DOSE displayed, and to 39.68 in, there was no statistical significance. Results : The average AGD using DOSE mode which is one of DR mammography AOP modes decreased by comparing to that of STD mode showing no difference in image quality. The use of DOSE is considered to be useful.

• 대한디지털의료영상학회논문지
• /
• 제14권1호
• /
• pp.1-6
• /
• 2012

This round of tests in patients with UGI and Esophagography data collected by national and international reference levels based on the original set of guidelines and fluoroscopy, through the provision of medical radiation exposure reduction and further optimization of Defense to realize that is intended. 359 names in our hospital underwent Esophagography 302 patients who underwent UGI average fluoroscopy time and number of images to calculate the average 21 cm Acryl phantom dose for 10 seconds and 20 seconds, average area dose and the area dose of 1 spot image, 5 spot consecutive images by measuring the patient dose and third quartile of the mean area dose was set seonryangin reference dose. Esophagography average patient dose was set to 30.05 $Gy{\cdot}cm^2$, DRL was set at a 25.37 $Gy{\cdot}cm^2$. Average dose of UGI patients were selected as 45.33 $Gy{\cdot}cm^2$, DRL was set at a 34 $Gy{\cdot}cm^2$. UGI patients with established average dose recommended in the 2008 national recommendation from the UGI examination with a dose of less than 49.7 $Gy{\cdot}cm^2$ seonryangin is evaluated. This Note examines the dose of self-aware through education recognizes the importance of dose reduction and examine if their efforts and further reduce patient dose could achieve optimization of the medical exposure is considered.

• 한국방사선학회논문지
• /
• 제14권5호
• /
• pp.613-618
• /
• 2020

간동맥화학색전술 중 사용되고 있는 Fast Low Dose C-arm CT의 평균선량을 DSA의 평균선량과 비교해 보고, 전체 누적선량에서 검사기법별 평균선량 분석을 통해 피폭선량을 분석해 보았다. 본원에서 환자 50명을 임의로 선정하여 Fast Low Dose C-arm CT와 DSA의 DAP 및 Air Kerma를 조사하여 비교하였으며, 4가지 검사기법(DSA, Fast Low Dose C-arm CT, Roadmap, Fluoroscopy)의 누적선량(DAP, Air Kerma)이 차지하는 비율을 분석하였다. 통계적인 비교 분석을 위해 통계프로그램 SPSS 20.0을 이용하여 대응표본 T검정, ANOVA 검증(post hoc test : Tukey)하였다. Fast Low Dose C-arm CT가 DSA에 비해 평균선량(DAP, Air Kerma)이 통계적으로 유의하게 낮았다.(p<.001) 간동맥화학색전술에서 항암제 주입 전후로 Fast Low Dose C-arm CT를 적극 활용하여 DSA의 검사 횟수를 줄인다면 환자의 의료방사선 피폭을 감소시킬 수 있다.

• 한국방사선학회논문지
• /
• 제11권5호
• /
• pp.321-328
• /
• 2017

D-Shuttle (Chiyoda Technol Corporation, Tokyo, Japan) 선량계를 이용하여 개인피폭관리 및 자연방사선량의 모니터링을 위한 기초자료를 제공하는데 연구의 목적이 있다. D-Shuttle을 이용하여 선량을 산출하였다. 선량보고서에서 400 일 노출되었을 때에 1.346 mSv 이었고, 연간선량 (annual dose per year)은 1.228 mSv/year, 평균시간선량 (average dose per hour)은 $0.014{\mu}Sv/hr$ 이었다. 국내의 개인 외부피폭선량 (1.295 mSv/year =Korea average natural individual external dose), 국내의 연간부가선량 (additional dose per year)은 -0.0663 mSv/year 이다. D-Shuttle은 방사선모니터링을 위한 개인선량계로 방사선의 검출성능 우수한 기능, 실시간 방사선 피폭관리, 방사선 작업의 경보 기능, 효율적이고 사용이 편리한 개인 방사선선량의 피폭관리로 ALARA에 매우 유용한 선량계로 사용할 수 있다. 방사선작업종사자와 지역주민의 방사선모니터링 측정기기로 병원, 산업, 의료현장, 원전사고 지역과 비파괴 분야의 위험한 지역에서 방사선모니터링으로 활용될 수 있다.

• Journal of Radiation Protection and Research
• /
• 제46권4호
• /
• pp.213-217
• /
• 2021

Background: Radiation exposure can occur as a result of occupational activities utilizing sources of radiation. The average level of occupational exposure is generally similar to the global average, but some workers receive more than this. In this study, the occupational exposure data for workers in Korea to check the recent trend of radiation exposure. Materials and Methods: The data collection and analysis are carried out by two separate periods based on the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) survey. One is the year 2003 to 2014 for a recent survey, and the other is 2015 to 2019. All available data were collected by annual reports from radiation dose registry organizations. Results and Discussion: The annual dose over the record level to the total workers did not change much compared with the total increasing number of workers in this period. The dose to the nuclear fuel cycle field has a tendency to decrease. It resulted from the efforts of radiation dose reduction with high technology introduced to this area. Also, it is important result that the radiation dose to the workers in radiography is remarkably reduced. Conclusion: The number of radiation workers and average doses were analyzed for occupational categories in Korea. It still needs cooperative efforts between the dose registry organizations for the efficient dose management of Korean radiation workers.

• 대한디지털의료영상학회논문지
• /
• 제14권2호
• /
• pp.47-56
• /
• 2012

Amount of radiation exposure by seeing through fluoroscopy examination while is many patient exposure administration and unprepared misgovernment be. In this study, abdominal fluoroscopy during the scan, the dose and image quality change according to the use of grid and added filter optimized by measuring the test condition is proposed. Uses seeing through fluoroscopy examination equipment of Image Intensifier of Easy Diagnost Eleva (Philips), under tube type and uses Human phantom and measures average area dose according to grid insertion existence and nonexistence and added filter kind change. Measure sum of 29 organ dose and effective dose through PCXMC imagination simulation program and image J program through noise, SNR, image distortion was measured. Resolution, sharpness, and analyzed using the MTF curves. Fluorography the grid to insert the filter thickness and thickening and increased the average area dose and organ doses and effective dose. In the case of spot examination, when inserted grid, average area dose and organ dose and effective dose increased. Filter thickens the average area dose decreased, but the organ doses and effective dose were increased when use 0.2mmCu+1mmAl filter, decreased slightly. Noise and SNR measurements without inserting the gird, if you do not use the added filter was the lowest and when measure the distortion, 0.1mmCu+1mmAl filter was no difference of image quality in case insert grid was judged that when did not use occasion added filter that do not use grid, difference of image quality does not exist. Did not show a big difference, according to the grid and uses of the added filter sharpness, and resolution. Patient dose increases with factors that reduce the quality of the image so reckless grid and the use of the added filter when abdominal fluoroscopy examination should be cautious in using.

• 한국방사선학회논문지
• /
• 제5권3호
• /
• pp.111-120
• /
• 2011

본 연구는 39개 1차 의료기관을 대상으로 유방촬영 장치의 정도관리 상태에서 실제 방사선 피폭선량을 측정하였다. 유방촬영 시 1차 의료기관의 방사선 피폭선량의 최적화와 진단참고준위값을 제시하고자 연구한 결과는 다음과 같다. 첫째, 영상의학과와 일반의원으로 구분하여 T-검정분석 결과 mAs는 영상의학과 80.16 mAs, 일반의원 77.22 mAs로 평균 78.58 mAs로 측정되었으며, 공기커마율은 영상의학과 8.94 mGy/mR, 일반의원 6.66mGy/mR로 평균 7.71 mGy/mR 측정되었다. 반가층은 영상의학과 0.40 mmAl, 일반의원 0.43 mmAl로 평균 반가층은 평균 0.42mmAl 측정되었고, 평균유선선량은 영상의학과 1.09 mGy 일반의원 1.19 mGy로 1.14 mGy로 측정되었다. 둘째, mAs, 반가층, 현상방법, SID를 두 그룹으로 구분하여 평균치를 T-검정 결과 SID에서 유의한 차이가 있는 것으로 나타났고(P<0.05), 영상의학과의 현상방법에서 현상기 사용 1.00 mGy, CR은 1.17 mGy로 mAs에서 유의한 차이가 있는 것으로 나타났다(P<0.05). 셋째, 항목별 상관분석에서는 평균유선선량에서 영상의학과는 mAs가 일반의원은 SID에서는 상관관계의 유의성이 있는 것으로 나타났다(P<0.05), 넷째, 항목별 회귀분석 결과 평균유선선량에서 mAs가 미치는 영향력은 22.7%, SID가 21.7%로 통계적으로 의미가 있었으며(P<0.05), 영상의학과의 평균유선선량에서 mAs가 미치는 영향력은 29.0%, 일반의원은 평균유선선량에서 SID가 미치는 영향력은 29.1%로 가장 많은 영향력이 있는 것으로 나타났다.

• 대한방사선기술학회지:방사선기술과학
• /
• 제37권2호
• /
• pp.101-107
• /
• 2014

이 연구는 디지털 유방확대촬영술에서 방사선 피폭을 감소시키며 영상의 질을 유지하기 위한 최적의 촬영조건을 알아보았다. 자동노출방식의 평균유선선량이 수동노출방식에 비해 높은 것으로 나타났다. 자동노출방식은 그리드(grid) 사용 여부에 따라 평균유선선량과 화질평가에 차이가 많았으나, 수동노출방식은 팬텀영상평가 점수에서만 차이가 있었다. 그러나 air gap technique을 사용할 경우 모든 노출방식에서 신호대잡음비의 증가가 뚜렷하게 나타났다. 따라서 유방확대촬영 시 air gap technique을 사용한다면 환자의 평균유선선량을 감소시키고 신호대잡음비를 높여 양질의 화질을 유지할 수 있을 것이다.