방사성 동위원소를 이용한 핵의학과 검사에서 병동 간호사의 방사선 피폭선량 평가

정재훈,이충운,유연욱,서영덕,최호용,김윤철,김용근,원우재,Jeong, Jae Hoon,Lee, Chung Wun,You, Yeon Wook,Seo, Yeong Deok,Choi, Ho Yong,Kim, Yun Cheol,Kim, Yong Geun,Won, Woo Jae 대한핵의학기술학회 2017 핵의학 기술 Vol.21 No.1

Purpose Radiation exposure management has been strictly regulated for the radiation workers, but there are only a few studies on potential risk of radiation exposure to non-radiation workers, especially nurses in a general ward. The present study aimed to estimate the exact total exposure of the nurse in a general ward by close contact with the patient undergoing nuclear medicine examinations. Materials and Methods Radiation exposure rate was determined by using thermoluminescent dosimeter (TLD) and optical simulated luminescence (OSL) in 14 nurses in a general ward from October 2015 to June 2016. External radiation rate was measured immediately after injection and examination at skin surface, and 50 cm and 1 m distance from 50 patients (PET/CT 20 pts; Bone scan 20 pts; Myocardial SPECT 10 pts). After measurement, effective half-life, and total radiation exposure expected in nurses were calculated. Then, expected total exposure was compared with total exposures actually measured in nurses by TLD and OSL. Results Mean and maximum amount of radiation exposure of 14 nurses in a general ward were 0.01 and 0.02 mSv, respectively in each measuring period. External radiation rate after injection at skin surface, 0.5 m and 1 m distance from patients was as following; $376.0{\pm}25.2$, $88.1{\pm}8.2$ and $29.0{\pm}5.8{\mu}Sv/hr$, respectively in PET/CT; $206.7{\pm}56.6$, $23.1{\pm}4.4$ and $10.1{\pm}1.4{\mu}Sv/hr$, respectively in bone scan; $22.5{\pm}2.6$, $2.4{\pm}0.7$ and $0.9{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. After examination, external radiation rate at skin surface, 0.5 m and 1 m distance from patients was decreased as following; $165.3{\pm}22.1$, $38.7{\pm}5.9$ and $12.4{\pm}2.5{\mu}Sv/hr$, respectively in PET/CT; $32.1{\pm}8.7$, $6.2{\pm}1.1$, $2.8{\pm}0.6$, respectively in bone scan; $14.0{\pm}1.2$, $2.1{\pm}0.3$, $0.8{\pm}0.2{\mu}Sv/hr$, respectively in myocardial SPECT. Based upon the results, an effective half-life was calculated, and at 30 minutes after examination the time to reach normal dose limit in 'Nuclear Safety Act' was calculated conservatively without considering a half-life. In oder of distance (at skin surface, 0.5 m and 1 m distance from patients), it was 7.9, 34.1 and 106.8 hr, respectively in PET/CT; 40.4, 199.5 and 451.1 hr, respectively in bone scan, 62.5, 519.3 and 1313.6 hr, respectively in myocardial SPECT. Conclusion Radiation exposure rate may differ slightly depending on the work process and the environment in a general ward. Exposure rate was measured at step in the general examination procedure and it made our results more reliable. Our results clearly showed that total amount of radiation exposure caused by residual radioactive isotope in the patient body was neglectable, even comparing with the natural radiation exposure. In conclusion, nurses in a general ward were much less exposed than the normal dose limit, and the effects of exposure by contacting patients undergoing nuclear medicine examination was ignorable. 목적: 핵의학 검사를 시행한 병동 환자의 시간과 거리에 따른 방사선량률을 측정하여 방사성동위원소 투여를 받은 환자가 병동 간호사에게 미치는 피폭을 예측하고 실제 총 피폭량과 비교하여 보고자 한다. 대상 및 방법: 병동에서 근무하고 있는 간호사 14명을 대상으로 열형광 선량계와 광자극 선량계를 이용하여 방사선 피폭선량을 측정하였고 핵의학 검사를 시행한 환자 50명(PET/CT 20명, Bone scan 20명, Myocardial SPECT 10명)을 대상으로 방사성동위원소 투여 직후와 검사시행 직후에 표면, 50cm, 1m에서 외부 방사선량률을 측정하였다. 측정 결과를 바탕으로 유효반감기를 도출한 후 병동 간호사가 받을 수 있는 피폭량을 예측하였다. 그리고 열형광선량계와 광자극선량계로 측정된 병동 간호사의 실제 총 피폭량과 비교 하였다. 결과: 병동 간호사 14명을 대상으로 한 피폭선량 측정결과 평균값과 최대값은 각각 분기당 0.01 mSv, 0.02 mSv 이었고 핵의학 검사를 시행 받은 환자의 선량률은 표면, 50cm, 1m 거리 순으로 PET/CT는 $376.0{\pm}25.2{\mu}Sv/hr$, $88.1{\pm}8.2{\mu}Sv/hr$, $29.0{\pm}5.8{\mu}Sv/hr$ 이고 Bone scan은 $206.7{\pm}56.6{\mu}Sv/hr$, $23.1{\pm}4.4{\mu}Sv/hr$, $10.1{\pm}1.4{\mu}Sv/hr$이고 Myocardial SPECT는 $22.5{\pm}2.6{\mu}Sv/hr$, $2.4{\pm}0.7{\mu}Sv/hr$, $0.9{\pm}0.2{\mu}Sv/hr$이다. 또한 검사를 시행한 후 측정한 선량률은 표면, 50cm, 1m 거리 순으로 PET/CT는 $165.3{\pm}22.1{\mu}Sv/hr$, $38.7{\pm}5.9{\mu}Sv/hr$, $12.4{\pm}2.5{\mu}Sv/hr$ 이고 Bone scan은 $32.1{\pm}8.7{\mu}Sv/hr$, $6.2{\pm}1.1{\mu}Sv/hr$, $2.8{\pm}0.6{\mu}Sv/hr$이고 Myocardial SPECT는 $14.0{\pm}1.2{\mu}Sv/hr$, $2.1{\pm}0.3{\mu}Sv/hr$, $0.8{\pm}0.2{\mu}Sv/hr$이다. 위의 결과를 바탕으로 유효반감기를 도출한 후 검사종료 30분 후 원자력안전법에서 규정하는 일반인 선량한도까지 도달하는데 걸리는 시간을 반감기를 고려치 않고 보수적으로 계산하면 PET/CT는 표면, 50cm, 1m 거리 순으로 7.9시간, 34.1시간, 106.8시간이며 Bone scan은 40.4시간, 199.5시간, 451.1시간이고 Myocardial SPECT는 62.5시간, 519.3시간, 1313.6시간이다. 결론: 본 연구 결과에 의하면 병동 간호사는 일반인 선량한도 보다 훨씬 적은 피폭량을 받는 것으로 나타나, 실질적으로 판단할 때 핵의학 검사를 시행한 환자로 인하여 받는 피폭의 영향은 미미한 것으로 판단된다.

류마토이드 관절염에서 슬관절의 관절경적 활액막 절제술

정재훈,박일성,양동현,Chung, Jae-Hoon,Park, Il-Sung,Yang, Dong-Hyun 대한관절경학회 1997 대한관절경학회지 Vol.1 No.1

There has been a controversy about the effectiveness of the synovectomy of the knee in the rheumatoid arthritis. So we studied to determine if the arthroscopic synovectomy of the knee was of benefit in the rheumatoid arthritis. We ana lysed 25 knees of 15 patients who underwent the arthroscopic synovectomy of the knee joint for their rheumatoid arthritis from Jun. 1995 to Oct. 1996. The average follow-up period was 20.1 months($12\~28$ months). The results were as follows; 1. Satisfactory results were obtained in 20 knees $(80\%)$ for the pain and the effusion each, 23 $(92\%)$ for the range of motion and 19 $(76\%)$ for the functional capacity. 2. In the overall results for the pain. effusion. range of motion and the functional capacity. we obtained excellent results in 14 knees $(56\%)$ and satisfactory results in 9 knees $(32\%)$. 3. In the patient's self assessment, 11 patients $(44\%)$ were delighted and 10 patients $(40\%)$ were satisfactory. 4. In the overall results according to the articular cartilage damage, satisfactory results were obtained in 15 $(93\%)$ out of 16 knees in Grade I and II, and 6 $(75\%)$ out of 8 knees in Grade III and IV. In conclusion, arthroscopic synovectomy could be one of very useful treatments for the rheumatoid knee. But further study is needed to get the long-term results of the synovectomy because there's many reports saying gradual decrease of good results with increasing time. And continuous and proper medical treatment including DMARDs, is needed to effectively control the rheumatoid arthritis even after the synovectomy.

THEODOLITE로 측정한 14 m 전파망원경의 주경면 모양

정재훈,김현구,김태성,정현수,박용선,Jung, Jae-Hoon,Kim, Hyun-Goo,Kim, Tai-Seong,Chung, Hyun-Soo,Park, Yong-Sun 한국천문학회 1997 天文學論叢 Vol.12 No.1

In order to reduce the small scale fluctuation resulting from shearing holograpy(Park et. al. 1997), differential panel adjustments were performed for 14 m radio telescope of Taeduk Radio Astronomy Observatory with T2 theodolite It appears that this method improves the surface accuracy by about $50\;{\mu}m$. The measured surface accuracy is, at best, $170\;{\mu}m$. The beam efficiency at 86.2 GHz is estimated to be 44% We also found that the elevation at which Park et. al. performed holography was too low.

정신과의사가 알아야 할 갑상선질환의 A부터 Z까지

정재훈,Chung, Jae-Hoon 한국정신신체의학회 2006 정신신체의학 Vol.14 No.2

갑상선질환은 비교적 흔한 질환으로 임상의사들이 쉽게 접할 수 있다. 그러나 갑상선질환 환자들은 전형적인 증상을 호소하는 경우부터 흔치 않는 임상상으로 병원을 찾는 경우까지 매우 다양하다. 간혹 정신과의사들이 심한 갑상선기능항진증을 조증 또는 가벼운 정신분열증으로 또는 심한 갑상선기능저하증을 우울증으로 자칫 오진하기 쉽다. 또한 갑상선 종양은 촉지되지 않는 경우까지 포함하여 전인구의 30% 이상에서 발견되고, 이중 최소 5% 이상은 악성종양이므로 갑상선 종양 환자의 접근 및 치료에 대해서도 개괄적인 이해가 필요하다. Thyroid disease is highly Prevalent, and many Physicians encounter the Patients with thyroid disease on many occasions. However, many doctors may make an erroneous diagnosis because of its variable clinical manifestation. Thyroid tumor is the most common disease which is detected in more than 30% of general population. Recently, the incidence of thyroid cancer is increasing to be a leading position in female cancer. Therefore, clinical physicians should be familiar with thyroid disease due to its high prevalence and heterogeneous clinical features.

가상현실 시스템(Virtual Reality System)을 이용한 훈련이 척수손상환자의 앉기 균형 및 일상생활동작에 미치는 영향

정재훈,Chung, Jae-Hoon 대한물리치료학회 2009 대한물리치료학회지 Vol.21 No.2

Purpose: This study was examined the effect of training using a Virtual Reality System on the sitting balance and Activities of Daily Living for patients with a spinal cord injury. Methods: The subjects were divided into an experimental (6 persons) and control group (5 persons). The experimental group trained the 5 programs, three times per week for 6 weeks using the Virtual Reality System and five days for week using conventional physical therapy. The control group trained five days for a week using conventional physical therapy. Results: The difference in the mean Spinal Cord Independence Measurement (SCIM) score in the experimental and control groups was increased to 8.33 and 6.60 (p=0.79), respectively. The difference in the mean functional reaching test in experimental and control group increased to 4.21 and 1.09 (p=0.25), respectively. The difference in the mean sitting time in experimental and control group increased to 41.05 and 10.33 (p=0.66), respectively. There was a difference in the mean of all variances but these differences were not statistically significant. Conclusion: These results suggest that training using the Virtual Reality System increased the SCIM, functional reaching test and sitting time in people with a spinal cord injury.

30㎒~300㎒ 대역의 자동차 방출 전계강도 측정 및 인체안전에 관한 연구

정재훈(Jae-Hoon Chung),공성훈(Sung-Hoon Kong) 한국생활환경학회 1999 한국생활환경학회지 Vol.6 No.1

콘크리트 균열깊이 측정용 소형초음파탐사기 개발을 위한 최적 탐촉자 연구

정재훈 ( Chung Jae-hoon ),이덕주 ( Lee Duck-ju ),이상범 ( Lee Sang-bum ),박윤제 ( Park Yoon-je ),이래철 ( Lee Rae-chul ) 한국구조물진단유지관리공학회 2008 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.12 No.1

In Concrete facility, Crack happen by various factor and the assessment of facility is carried by the evaluation of crack. The characteristics of crack are divided into the type of crack, the width of crack, the depth of crack, the number of crack. The type of crack, the width of crack, the number of crack are checked sufficiently by the naked eye, but because the depth of crack are occured under the inside of concrete, it is difficult to check and it has insufficient accuracy. Nowadays the Ultrasonic system are applied to various cases because of the aspect of economy and simplicity, non-destruction. In this paper, we studied the sensor that is the important element of ultrasonic system and carried out research about the position of ultrasonic generation and quality by the shape variation of sensor.

소규모 산업 폐열회수용 열전발전시스템의 출력 특성에 관한 실험적 연구

정재훈(Jae-Hoon Chung),김우철(Woochul Kim),이진호(Jinho Lee),유태우(Taeu Yu) 대한기계학회 2010 大韓機械學會論文集B Vol.34 No.4

본 연구에서는 폐열 회수를 위한 열전 발전 시스템을 구성하였다. 열전 모듈은 스테인레스 스틸덕트 내부에 부착되고, 뜨거운 공기를 불어넣는 장치가 덕트의 입구에 마주한 형태를 취하였다. 이 때 고온부의 온도가 균일한 상태에서 낼 수 있는 최대 파워를 구해내었다. 결과적으로 모듈에 가해지는 최적화된 압력이 있었다. 또한 열전 발전의 성능을 열전 모듈의 저온부의 열 싱크에 의하여 결정되었다. 자연대류 형식의 열 싱크에서 낼 수 있는 파워가 5배 가량 차이가 났다. In this study, a thermoelectric power generation system was constructed for a waste-heat recovery. Thermoelectric modules were attached to a stainless steel duct, and a hot air blower was set such that it faced the duct inlet. We found that to achieve the maximum power out of the system, the temperature in the hot side of the thermoelectric module should be uniform. The optimum compressive pressure exerted on the module was observed. Further, the thermoelectric power performance was evaluated using the heat sink attached to the cold side of the thermoelectric module. In particular, when using a natural-convection heat sink, the power output difference is approximately five times.

설계VE시 브레인스토밍을 효과적으로 수행하기 위한 아이디어 창출기법

정재훈(Jae-Hoon Chung),김영선(Young-Sun Kim) 대한토목학회 2005 대한토목학회지 Vol.53 No.12

콘크리트 균열깊이 측정용 소형 초음파 탐사기 개발을 위한 초음파 특성연구

정재훈 ( Chung Jae-hoon ),이상범 ( Lee Sang-bum ),박윤제 ( Park Yoon-je ),이래철 ( Lee Rae-chul ),신은우 ( Shin Eun-woo ) 한국구조물진단유지관리공학회 2007 한국구조물진단유지관리공학회 학술발표대회 논문집 Vol.11 No.2

Generally Ultrasonic instruments have many error in measuring concrete crack depth, and use many formulas for calculating concrete crack depth. For improving the reliability of results, there must be needed both uniform method and accurate instrument. If there are accurate measurement, adequate remedy and reinforcement in time, we can maximize life cycle of concrete structures by the improvement of concrete curability. If we estimate the damages of structure through accurate crack depth measurement and prevent the collapse of facilities by maximizing the safety of structure, people can use safely facilities and structures. In this study, we study the characteristics of ultra sonic wave for developing Small Ultra Sonic System for measuring Concrete Crack Depth.