휠체어에서 호흡수와 심박수 측정 및 이벤트 전송

한동균,김종명,홍주현,차은종,이태수,Han, Dong-Kyoon,Kim, Jong-Myoung,Hong, Joo-Hyun,Cha, Eun-Jong,Lee, Tae-Soo 대한의용생체공학회 2008 의공학회지 Vol.29 No.6

The purpose of this study is to measure both ECG and BCG(Ballistocariograph) signal of a subject on moving or resting wheelchair and detect the heart rate and respiratory rate and transmit an event message to remote server on emergent situation. To acquire ECG and BCG data, amplifier circuits were composed to be suitable for their characteristics. The output signals were converted to digital data and stored in bio-signal archiving media(SD card). CDMA module was used to transmit the event data on ECG electrode detachment and the received data was monitored by the developed C# application program. 5 volunteers participated in the experiment to evaluate the validity of the developed device. When the event occurs in each subject, 48 Kbyte data, stored for 32 seconds from that point, was transmitted to remote server through CDMA cellular phone network correctly. The received data of ECG, BCG, and 3-axial acceleration could be archived in server and the heart rate and respiratory rate could be measured and analyzed. The developed device in this study could acquire the ECG and BCG data of subjects on wheelchair simultaneously and measure their heart rate and respiratory rate. In addition, event data was verified to be transmitted to remote server without any errors.

CT장치의 성능평가에 관한 연구

한동균,김문찬,양한준,고신관,Han Dong Kyoon,Kim Moon Chan,Yang Han Joon,Ko Shin Kwan 대한방사선사협회 2001 대한방사선사협회지 Vol.27 No.2

In medical equipments as complex as a computed tomographic equipment, routine quality control procedures are essential to the detection of small pathologic change in soft tissue as well as and the maintenance of optimal image quality. This study was condu

재구성 알고리즘 변화에 따른 CT 영상의 화질 평가

한동균,박건진,고신관,Han, Dong-Kyoon,Park, Kun-Jin,Ko, Shin-Kwan 대한디지털의료영상학회 2010 대한디지털의료영상학회논문지 Vol.12 No.2

In this study, the correlation among the changes of Modulation Transfer Function(MTF) in the noise and high-contrast resolution and the change of Contrast to noise ratio(CNR) in the low-contrast resolution will be examined to investigate the estimation of image quality according to the type of algorithms. The image data obtained by scanning American Association of Physicists in Medicine(AAPM) phantom was applied to each algorithm and the exposure condition of 120 kVp, 250 mAs, and then the CT number and noise were measured. The MTF curved line of the high-contrast resolution was calculated with Point Spread Function(PSF) by using the analysis program by Philips, resulting in 0.5 MTF, 0.1 MTF and 0.02 MTF respectively. The low-contrast resolution was calculated with CNR and the uniformity was measured to each algorithm. Since the measurement value for the uniformity of the equipment was below ${\pm}$ 5 HU, which is the criterion figure, it was found to belong to the normal range. As the algorithm got closer from soft to edge, the standard deviation of CT number increased, which indicates that the noise increased as well. As for MTF, 0.5 MTF, 0.1 MTF and 0.02 MTF were all sharp algorithms, and as the algorithm got closer from soft to edge, it was possible to distinguish more clearly with the naked eye. On the other hand, CNR gradually decreased, because the difference between the contrast hole CT number and the acrylic CT number was the same while the noise of hole increased.

X-선 장치의 기술적 인자의 변화에 따른 선량 비교 평가

한동균,고신관,선종률,윤석환,정재은,Han, Dong-Kyoon,Ko, Shin-Gwan,Seon, Jong-Ryul,Yoon, Seok-Hwan,Jung, Jae-Eun 대한디지털의료영상학회 2009 대한디지털의료영상학회논문지 Vol.11 No.2

With the recent development of diagnosis using radiation and increasing demand of the medical treatment, we need to minimize radiation exposure dose. So, This is the method which reduce patient dose by measuring surface dose of radiographic change factor and by comparing theoretical and actual dose, when we take an X-ray which is generally used. By changing the factor of kV, mAs, FSD, whose range is 60 to 120 kV, 20 to 100 mAs, 80 to 180 cm, we compared theoretical surface dose with actual surface dose calculated by the simple calculation program, Bit system, and NDD-M method As a result, when kV and mAs were higher, theoretical surface dose and actual surface dose were more increased. but the higher FSD was, the more decreased surface dose was. According to this, the error were measured about 0.1 to 0.2 mGy in low dose part and about 0.7 to 1.5 mGy in high dose part. Therefore, this shows that theoretical surface dose calculation method is more correct in low dose part than in high dose part. In conclusion, we will have to make constant efforts which can reduce patient and radiographer's exposure dose, studying methods which can predict patient's radiation exposure dose more exactly.

MDCT에서 화질과 방사선량에 관한 연구

한동균(Dong-Kyoon Han),고신관(Shin-Gwan Ko),양한준(Han-Joon Yang),김문찬(Moon-Chan Kim) 대한방사선과학회(구 대한방사선기술학회) 2007 방사선기술과학 Vol.30 No.2

  본 연구는 MDCT장치에 있어 화질평가와 선량평가 방법을 통하여 장치의 항상성을 유지하며 양질의 의료영상을 제공하는 기초자료로 사용함과 더불어, MDCT의 각 장비에 따른 선량을 평가하고 제시하고자 서울소재 14대의 MDCT장치를 대상으로 시행하여 그 기준을 정량화 하였다.<BR>  MDCT를 이용한 화질측정 즉, CT number와 노이즈, 균일도, 공간분해능, 대조도 분해능과 선량 측정 즉, CTDI와 CTDI<SUB>W</SUB>, CTDI<SUB>W</SUB>/100㎃s의 결과는 다음과 같았다.<BR>  CT number는 평균 0.56±0.70HU, 노이즈는 평균 0.39±0.09HU, 균일도는 평균 1.08±0.52HU이었다. 그리고 공간분해능은 평균 0.48±0.05㎜, 대조도 분해능은 평균 3.65±1.16㎜이었다. CTDI는 head phantom을 이용한 경우 중앙부는 평균 43.2±15.4m㏉, 주변부는 45.6±17.5m㏉이었다, 그리고 body phantom에 있어 중앙부 평균은 13.5±4.5m㏉, 주변부는 29.2±10.2m㏉이었다. 주변부가 중앙부에 비해 2.16배 증가되어 나타났다. head phantom을 이용한 경우 CTDI<SUB>W</SUB><SUB></SUB>는 평균 44.8±16.8m㏉, CTDI<SUB>W</SUB>/100㎃s는 평균 18.8±5.3m㏉, body phantom을 이용한 경우 CTDI<SUB>W</SUB>는 평균 24.0±8.3m㏉이고, CTDI<SUB>W</SUB>/100㎃s는 평균 10.1±2.5m㏉이었다.<BR>  위에서 알 수 있듯 MDCT의 CT number와 노이즈, 균일도, 공간분해능, 대조도 분해능과 CTDI와 CTDI<SUB>W</SUB>, CTDI<SUB>W</SUB>/100㎃s는 전체 장치에서 모두 우수하게 나타났다.   The Purpose of this study is to suggest the basic data for making good quality image and maintaining equipment homeostasis by accepting image quality evaluation and radiation dose evaluation in Multi- detector CT. In this study we surveyed 14 CT equipments in Seoul. The results obtained were as follows; CT number was 0.56±0.70HU. Noise was 0.39±0.09HU.<BR>  Uniformity was 1.08±0.52HU. High contrast resolution was 0.48±0.05㎜ and low contrast resolution was 3.65±1.16㎜. For CTDI, the central part and the peripheral part of head phantom were 43.2±15.4m㏉ and 45.6±17.5m㏉, respectively. For body phantom, the central part and the peripheral part of head phantom were 13.5±4.5 and 29.2±10.2m㏉, respectively.<BR>  CTDI<SUB>W</SUB> was 44.8±16.8m㏉ and CTDI<SUB>W</SUB>/100㎃s was 18.8±5.3m㏉ using head phantom. CTDI<SUB>W</SUB> was 24.0±8.3m㏉ and CTDI<SUB>W</SUB>/100㎃s was 10.1±2.5m㏉ using body phantom.<BR>  The refore, CT number, noise, high contrast resolution, low contrast resolution, CTDI, CTDI<SUB>W</SUB> and CTDI<SUB>W</SUB>/100㎃s of MDCT were showed excellently in all equipments.

고정밀도의 단상전파정류형 X선 장치의 제작 및 평가

한동균(Han, Dong-Kyoon),정재은(Jung, Jae-Eun),최준구(Choi, Jun-Gu),성렬훈(Seoun, Youl-Hun),고신관(Ko, Shin-Gwan) 한국산학기술학회 2011 한국산학기술학회논문지 Vol.12 No.1

1950년대 진단용 X선 장치의 국산화가 이루어졌으며, 1960년 초부터 진단용 X선 장치의 수요가 급격히 증 가함에 따라 생산업체의 증가로 의료기기 시장의 많은 발전을 가져왔다. 진단용 X선 장치는 방사선에 대한 인체의 위험 요소인 피폭문제가 있기 때문에 보건복지가족부가 제조, 설치기준을 제정하고 있으며, 이를 기본으로 하여 KS A 4019, KS A 4021, KS A 4022 등에 의해 정밀한 제작이 이루어지고 있다. 진단용 X선 발생장치는 단상 전파 정 류형과 삼상 전파 정류형이 대부분이나, 1980년대 이후 인버터식 X선 발생장치로 대부분 전환되기 시작하였다. 인버 터식 X선 발생장치는 단상 전파정류형 X선 발생장치에 비해 1.5~1.8배의 높은 출력과 단시간 제어가 정확하지만, 가 격이 비싸기 때문에 개인병원에서는 단상전파정류형 X선 장치를 선호하고 있어 단상 전파정류형 X선 장치의 성능개 선이 요구된다. 이에 본 연구자들은 단상 전파정류형 X선 발생장치의 제어장치, 고전압 변압기, 필라멘트 가열변압 기, 정류회로, 고압케이블 등 기기의 구성요소를 제작하고 진단용 X선 발생장치의 성능평가를 시험하였으며, 그 결과 국내 규정인 진단용 방사선 발생장치의 안전관리 규칙에 적합한 기준을 얻을 수 있었다. Diagnosis X-ray equipment localized at 1950's but it is developed suddenly at 1960's with demand together. Manufacture of Diagnostic X-ray equipment is controled by the KS regulation and the Ministry of Health and Welfare because of hazardous element etc. exposure by radiation. Most of diagnostic X-ray equipment ware single phase and three phase full-wave rectification but from 1980's it transforms it was exchanged in inverter type X-ray equipment. Inverter type X-ray equipment produces approximately 50~80% more average photon intensity then single phase full-wave rectification and the accuracy is high. But from a clinic it dose not use because expensive therefor the efficiency improvement of single phase full-wave rectification is necessary. We produced single phase full-wave rectification X-ray equipment control unit, high tension transformer, filament heating transformer, rectification circuit, high tension cable and others and evaluated efficiency, in result which is excellent compare with Rule of Safety Management and KS regulation

소아 방사선 검사 시 안전 안내문이 보호자의 불안감 해소에 미치는 영향

홍기장(Ki-Jang Hong):한동균(Dong-Kyoon Han),김종진(Jong–,Jin Kim),이현국(Hyeon-Kook Lee) 대한영상의학기술학회 2017 대한영상의학기술학회 논문지 Vol.2017 No.1

Purpose:As the national income level increases, frequent diagnostic tests are conducted at the advanced medical level, and radiation exposure during diagnosis may gradually increase. The number of caregivers who are interested in raising children is increasing, and the number of pediatric upper extremity X-ray examinations is increasing every year. However, unfamiliar hospital environments and unclear radiation fears have a psychological negative impact on caregivers. As a health care provider, we should not be overlooked. This is also a stressful event for parents who care for children as well as children. Materials and Methods:From March 2016 to August 2016, 300 guardians of children who had upper- extremity X-ray test(left hand growth plate test) in the department of radiology of Eulji University hospital were included in this study. We directly explained to guardians by suing the pediatric radiation safety manual, made based on the author s previous article Measure and Reduce the exposure dose during examination of child s growth plate using left hand x - ray“ We evaluated efficacy of radiation exposure guidelines for children with upper-extremity X-ray examination (left hand growth plate test) Hospital in the Department of Radiology of Pediatric Radiology. Subject s gender, age, education level, number of children, and annual number of radiological examinations of children were included by general characteristics. The understanding, interest of radiation, and degree of anxiety was measured in the range of 1 to 10. Result:The mean level of understanding of radiation was 4.94 on the 10 point scale, The average degree of concern for radiation is 8.09. Compared to comprehension, interest was high. Of the four groups, the second group had the lowest level of understanding of radiation and the group with the highest level of interest. The pre - stress intensity was the highest at 6.91 and the post - stress intensity was the lowest at 1.22. The mean score of the psychological anxiety score in the pre - evaluation was 7.07 and the psychological anxiety score in the post - evaluation was 1.41. The psychological anxiety was largely resolved. Conclusion:When discussing using the Pediatric Radiation Safety Guidelines, anxiety scores were statistically significantly lower in health care services. This is the result of environmental improvements that are effective in reducing parental anxiety. The higher the satisfaction, the higher the loyalty and the more likely you will return to the hospital. Patient loyalty is therefore important to attract more patients to the hospital and this study is considered effective in increasing patient satisfaction. 목 적:본 연구는 대전의 일개 병원 영상의학과에서 선량의 측정치와 방사선에 대한 안내를 기재한 방사선 안내문을 자체 제작하여 소아방사선 촬영 시 보호자가 갖게 되는 불안감을 해소하고자 하였다. 의료 서비스로서 검사 전 소아 방사선 안전에 대해 면접 설명하고 이 활동의 유무에 따른 소아의 보호자의 방사선에 대한 막연한 두려움의 심리변화와 유용성을 설문 조사하여 보호자의 심리적 변화에 소아 방사선 안전 안내문 면접설명이 어떠한 영향을 주는가에 관한 서비스만족 지향의 효과를 검증하고자 한다. 대상 및 방법: 1) 평가대상 : 본 연구의 대상자는 대전광역시 서구에 위치한 E대학교 병원(이하 병원)의 영상의학과에 소아 성장 판검사(소아 상지 왼손 X-ray검사)를 위해 내원한 소아(만 5세∼13세)의 보호자 300명으로 의사소통이 가능하고 국문 해독이 가능한 보호자. 2) 평가기간 : 2016년 3월 1일부터 2016년 8월31일 까지 6개월. 3) 평가도구 : 방사선 안전 안내문과 설문지를 통한 만족도 조사. 4) 자료수집방법 : 설문지를 통한 스트레스 강도측정 및 안전 안내문의 면접설명을 통한 사전, 사후 만족도 조사. 5) 분석방법 : 설문 내용을 갖고 SPSS Vs18.0 (SPSS, Chicago, USA)을 사용하여 모집단 (소아의 보호자)의 일반적 특성과 소아 방사선에 대한 이해도와 관심도의 빈도분석과 면접설명 유무에 따른 스트레스 강도가 어느 정도 차이를 보이는지 교차 분석하여 비교하였다. 결 과:소아의 보호자인 모집단의 인구학적인 특성을 분석하였고 소아 방사선에 대한 이해도와 관심도를 빈도 분석하였다. 면접설명 유무에 따른 스트레스 강도가 어느 정도 차이를 보이는지 알 수 있었으며 그 효과에 대해 검증할 수 있었다. 결 론:보호자의 방사선에 대한 두려움과 보호자의 문의 및 민원을 해소할 수 있었고 영상의학과의 긍정적 이미지 고취 시킬 수 있었다. 차 후 안전 안내문의 형태적 측면으로 미디어 매체와 같이 시청각 자료를 통한 접근 또는 보호자의 인구학적 특성을 고려한 개발된 도구의 활용은 그 효과를 더욱 증폭시킬 수 있으리라 사료된다.

US elastography에서 Parameter변화에 따른 Custom elasticity phantom과 간 실질의 탄성도 및 진단적 가치 평가

송한현(Han-Hyeon Song),장하나(Ha-Na Jang),정해승(Hae-Seung Jung),조수빈(Soo-Bin Cho),허은정(Eun-Joeng Heo),김범준(Beom-Jun Kim),한동균(Dong-Kyoon Han) 대한초음파의료영상학회 2018 대한초음파의료영상학회 학술대회 초록집 Vol.3 No.1

소아 복부 CT 검사에서 체중에 기반한 조영제 주입 프로토콜 : 적용에 따른 조영증강의 최적화

김영균(Yung-Kyoon Kim),한동균(Dong-Kyoon Han) 한국방사선학회 2021 한국방사선학회 논문지 Vol.15 No.5

본 논문의 목적은 복부 CT 검사를 시행하는 소아환자에게 체중 기반 조영제 프로토콜을 적용함으로써 고정 투여법보다 조영제를 감소시키면서 최적의 문맥기 화질을 달성하는 것이다. Discovery 750HD(General Electric medical systems, Milwaukee, USA)를 이용하였으며, 만 18세 미만의 소아 남자 85명과 여자 82명, 총167명을 대상으로 연구하였다. 300 mgI/ml(Xenetix, Guerbet, France)의조영제를 몸무게 2배로 고정 주입한 그룹과 체중기반 프로토콜을 적용하면서 주입량을 10%씩 단계적으로 감소시키면서 생리식염수를 주입한 그룹을 구분하였으며, 스캔 지연 시간을 추가로 변화시키면서 복부 장기의 CT 감쇄계수와 SNR을 비교 평가하였다. 또한 조영 증강의 정도와 심장 주변의 빔 경화 인공물을 정성적으로 평가하였다. 체중기반 프로토콜을 적용하고 20%의 조영제를 감소한 그룹이 몸무게 2배로 고정 주입한 그룹과 조영 증강이 가장 유사하였으며, 그리고 20%의 지연시간을 가진 그룹이 가장 조영 증강 효과가 높았다. 조영제 주입 후 적절한 지연시간은 실질 장기의 조영 효과를 상승시켰으며, 생리식염수를 적용한 주입 프로토콜은 심장 주변의 인공물이 감소시켰다. 결론적으로 소아 복부 CT 검사 시, 체중 기반 프로토콜의 적용과 적절한 지연시간의 조절은 불필요한 조영제 사용을 억제하고 최적의 문맥기 영상의 특성화를 가능하게 한다. The aim of this study was to achieve optimal portal phase while reducing contrast medium by applying weight-based dose protocol compared to standard fixed dose protocol to performing of pediatric abdominal CT examination. Discovery 750HD (General Electric Medical Systems, Milwaukee, USA) was used, and a total of 167 children consisting of 85 men and 82 women under the age of 18 were studied. The group in which the 300 mgI/ml(Xenetix, Guerbet, France) contrast medium was fixedly injected at twice body weight and the group injected with physiological saline while gradually decreasing the injection amount by 10% while applying the weight-based protocol were distinguished. Also, the CT number and SNR of abdominal organs were compared and evaluated while changing the scan delay time. Subjective image quality of enhancement and beam-hardening artifacts of around the heart was assessed with five-point criterion. The group adapted weight-based protocol with 20% reduction in contrast medium was most similar in contrast enhancement in the group with fixed injection at twice body weight. Furthermore, the group with a delay time of 20% had the highest contrast enhancement effect, and the difference in CT attenuation coefficient from the group scanned immediately after injection of the contrast media. Therefore, the appropriate delay time after injection of the contrast agent increased the contrast enhancement of the parenchymal organ. In addition, the weight-based injection protocol with normal saline reduced artifacts around the heart, and the effect of contrast enhancement could be maintained. In conclusion, it is possible to reduce dosage of contrast media through the application of weight-based injection protocols and appropriate latency, and to characterize optimal portal phase imaging on pediatric abdominal CT.

자동노출제어장치를 이용한 비정질 실리콘 평판형 검출기에서 격자의 조건에 따른 환자선량 변화와 촬영 거리의 변화가 검출기 획득선량에 미치는 영향

윤석환,최준구,한동균,Yoon, Seok-Hwan,Choi, Jun-Gu,Han, Dong-Kyoon 대한디지털의료영상학회 2007 대한디지털의료영상학회논문지 Vol.9 No.2

This study attempts to propose an appropriate method of using digital medical imaging equipments, by studying the effects of automatic exposure control(AEC), grid ratio and the change of radiography distance on the patient dose and detertor acquisition dose during the procedure of acquiring image through a digital medical imaging detector. The change of dose following the change of grid ratio's exposure and radiography distance was measured, by using an abdominal phantom organized with tissue equivalent materials in an amorphous silicon thin film transistor detecter installed with AWC. The case to use grid ratio 12 : 1, focal distance 180cm to radiography distance 110cm in AEC, the patient dose increased rather when we used grid ration 10 : 1, focal distance 110cm. When AEC was not used,the dose necessary for image acquisition decreased as the grid ratio became higher and the distance became further. but detector acquisition dose was not reduced when in applied AEC. When purchasing digiral medical imaging equipments, optional items such as AEC and grid shall be accurately selected to satisfy the use of the equipments. Radiography error made by radiation technologist and unnenessary patient dose can be reduced by selecting equipments with a radiography distance marker equipment when it did not apply AEC. These equipments can also be helpful in maintaining high imaging quality, one of the merits of digital detectors.