전산화단층영상을 이용한 복부 지방 계측법에서 호흡운동이 비만도 측정에 미치는 영향

성열훈,Seoung, Youl-Hun 대한의용생체공학회 2012 의공학회지 Vol.33 No.1

The purpose of this study was to evaluate how much effect to accuracy when measuring abdominal fat by Computed Tomography (CT) under different respiration movements. The study volunteer composed of 66 normal adults ($50.4{\pm}11.2$ years, 33 males, 33 females). We measured their obesity by using Broca index, body mass index (BMI) and CT and have investigated the correlation. The CT scanning for the obesity measurement have done in two ways, one was done in stopping breath after exhaling and the other was holding a breath after inhaling. The results showed no statistically significant difference among the three measuring techniques. And, the error in two ways of inhaling and exhaling was showed 24.2% of volunteers. The two ways of respiration movements made different result in visceral fat area (P = 0.044), subcutaneous fat area (P = 0.636) and abdominal obesity value (P = 0.012). This study demonstrates that the two ways of respiration movements when scanning CT makes change in accuracy in visceral fat area, and in abdominal obesity quantitative measure. Therefore, our study suggests that CT should take twice in two ways while a patient stops breath after exhaling and holds a breath after inhaling when measuring abdominal obesity using CT equipments.

3차원 의료영상진단기기를 이용한 가상 전립선 용적 측정

성열훈,주용현,최보영,Seoung, Youl-Hun,Joo, Yong-Hyun,Choe, Bo-Young 대한의용생체공학회 2010 의공학회지 Vol.31 No.4

Recently, advance on various modalities of diagnosing, prostate volume estimation became possible not only by the existing two-dimension medical images data but also by the three-dimensional medical images data. In this study, magnetic resonance image (MRI), computer tomography (CT) and ultrasound (US) were employed to evaluate prostate phantom volume measurements for estimation, comparison and analysis. For the prostate phantoms aimed at estimating the volume, total of 17 models were developed by using devils-tongue jelly and changing each of the 5ml of capacity from 20ml to 100ml. For the volume estimation through 2D US, the calculation of the diameter with C9-5Mhz transducer was conducted by ellipsoid formula. For the volume estimation through 3D US, the Qlab software (Philips Medical) was used to calculate the volume data estimated by 3D9-3Mhz transducer. Moreover, the images by 16 channels CT and 1.5 Tesla MRI were added by the method of continuous cross-section addition and each of imaginary prostate model's volume was yielded. In the statistical analysis for comparing the availability of volume estimation, the correlation coefficient (r) was more than 0.9 for all indicating that there were highly correlated, and there were not statistically significant difference between each of the correlation coefficient (p=0.001). Therefore, the estimation of prostate phantom volume using three-dimensional modalities of diagnosing was quite closed to the actual estimation.

64 다중 검출기 전산화단층촬영에서 관전류 자동노출조절 기법을 이용한 두개부 방사선량 감소 정도 평가

성열훈,김영옥,최보영,Seoung, Youl-Hun,Kim, Yong-Ok,Choe, Bo-Young 한국의학물리학회 2010 의학물리 Vol.21 No.2

64 multi-detector computed tomography (MDCT)에서 두개부의 과도한 선량이 문제가 되어 고정관류기법과 관전류 자동노출조절(automatic exposure control, AEC) 기법을 이용하여 선량 감소 정도를 비교 평가하고자 한다. 연구에 사용한 장비는 Siemens사의 SOMATOM Definition 64 multi-detector CT를 이용했으며, Whole body phantom (KUPBU-50, Kyoto Kagaku CO. Ltd)의 두개부를 사용했다. 실험 protocol은 helical scan 방식을 적용하여 120 kVp, rotation time은 1 sec, slice thickness와 increment는 각각 5 mm, FOV는 250 mm, matrix size는 $512{\times}512$, collimation은 $64{\times}0.625\;mm$, pitch는 1로 조사하였다. 선량감소효과의 측정방법은 관전류를 350 mAs로 고정한 방법과 AEC 기법을 적용한 방법으로 나누어 평가하였으며, 영상품질은 CT number의 표준편차를 이용하여 영상의 잡음을 측정하였다. 이 때 두개부(craniofacial bone)는 머리덮개뼈(calvaria) 끝부분에서 눈썹활(superciliary ridge)까지를 1구역, 논썹활 아래부터 코가시점(acanthion)까지를 2구역, 그리고 코가시점 아래부터 턱(mentum)끝까지를 3구역으로 정의하여 측정하였다. 고정관류기법에서 구역별로 CTDIvol은 57.7 mGy였으며, DLP는 $640.2\;mGy{\cdot}cm$로 동일하였다. AEC 기법을 적용한 1구역은 CTDIvol: 30.7 mGy, DLP: $340.7\;mGy{\cdot}cm$, 2구역은 CTDIvol: 46.5 mGy, DLP: $515.0\;mGy{\cdot}cm$, 그리고 3구역은 CTDIvol: 30.3 mGy, DLP: $337.0\;mGy{\cdot}cm$으로 나타났다. 영상품질을 나타내는 CT number의 표준편차는 1구역에서 고정 관류기법은 2.6, AEC 기법은 3.0, 2구역에서 고정 관류기법은 3.1, AEC 기법은 3.4, 3구역에서 고정 관류기법은 2.7, AEC 기법은 3.2으로 측정되었다. 64 MDCT에서의 AEC 기법은 기존의 고정관류법에 비해 안구, 이하선 그리고 갑상선 부위에 대해 큰 선량 감소효과가 나타났으며, 두개부의 방사선량을 감소시키는데 매우 유용한 기법으로 사료된다. The purpose of this study was to evaluate the usefulness of reducing of craniofacial radiation dose using automatic exposure control (AEC) technique in the 64 multi-detector computed tomography (MDCT). We used SOMATOM Definition 64 multi-detector CT, and head of whole body phantom (KUPBU-50, Kyoto Kagaku CO. Ltd). The protocol were helical scan method with 120 kVp, 1 sec of rotation time, 5 mm of slice thickness and increment, 250 mm of FOV, $512{\times}512$ of matrix size, $64{\times}0.625\;mm$ of collimation, and 1 of pitch. The evaluation of dose reducing effect was compared the fixed tube current of 350 with AEC technique. The image quality was measured the noise using standard deviation of CT number. The range of craniofacial bone was to mentum end from calvaria apex, which devided three regions: calvaria~superciliary ridge (1 segment), superciliary ridge~acanthion (2 segment), and acanthion~mentum (3 segment). In the fixed tube current technique, CTDIvol was 57.7 mGy, DLP was $640.2\;mGy{\cdot}cm$ in the all regions. The AEC technique was showed that 1 segment were 30.7 mGy of CTDIvol, 340.7 $mGy{\cdot}cm$ of DLP, 2 segment were 46.5 mGy of CTDIvol, $515.0\;mGy{\cdot}cm$ of DLP, and 3 segment were 30.3 mGy of CTDIvol, $337.0\;mGy{\cdot}cm$ of DLP. The standard deviation of CT number was 2.622 with the fixed tube current technique and 3.023 with the AEC technique in the 1 segment, was 3.118 with the fixed tube current technique and 3.379 with the AEC technique in the 2 segment, was 2.670 with the fixed tube current technique and 3.186 with the AEC technique in the 3 segment. The craniofacial radiation dose using AEC Technique in the 64 MDCT was evaluated the usefulness of reducing for the eye, the parotid and thyroid with high radiation sensitivity particularly.

3차원 볼륨 렌더링을 이용한 가상 돌출형 전립선 부피 평가

성열훈,주용현,임재동,최보영,Seoung, Youl-Hun,Joo, Yong-Hyun,Rhim, Jae-Dong,Choe, Bo-Young 한국의학물리학회 2009 의학물리 Vol.20 No.4

2차원의 영상을 이용한 돌출형 전립선 비대증의 부피 평가방법에서 돌출부위를 포함시킬 경우와 포함시키지 않을 경우의 부피변화를 3차원 볼륨 렌더링(volume rendering, VR)을 이용하여 비교 평가하고자 한다. 돌출형 전립선 부피측정을 위한 가상 전립선 모델은 곤약을 이용해 임의로 평균 1 cm 정도로 돌출되도록 하여 10 ml에서 각각 10 ml씩 부피를 변화시켜 100 ml까지 총 10 개의 모델을 제작하였다. 이 때 제작된 모델의 부피측정은 64 channel 전산화단층촬영(computed tomography, CT)과 3.0 Tesla 자기공명영상(magnetic resonance image, MRI)을 이용하여 획득된 3차원 볼륨 영상자료로 계측하였다. 산출한 CT와 MRI영상들의 3차원 볼륨데이터 근접성 평가를 위해 wilcoxon 부호순위(signed rank) 검정을 하였다. 또한 획득한 영상자료는 3차원 영상처리를 통하여 볼륨 렌더링으로 재구성한 후 타원체부피공식법을 이용하여 돌출부위를 포함시킬 때와 포함하지 않을 때의 부피를 구하였다. 이 때 돌출 유무에 따라 각각 측정된 부피와 3차원 볼륨 렌더링의 부피를 wilcoxon 부호순위(signed rank) 검정을 사용하여 유의성을 평가했으며 상관계수(pearson's correlation coefficient, r)를 사용하여 상관관계를 분석하였다. 계측된 가상 전립선 모델의 돌출부위길이는 CT에서 $0.90{\pm}0.18\;mm$, MRI에서 $0.75{\pm}0.11\;mm$이었으며, CT와 MRI에서 계측된 3차원 영상 부피의 p-value는 0.414로 유의한 차이는 없었다. 그러나 MRI에서 측정된 3차원 영상 부피와 2차원 영상에서 돌출부위를 포함시킬 때의 p-value는 0.005인 반면 포함하지 않을 때의 p-value는 0.139로 나타났으며, CT에서도 측정된 3차원 영상 부피와 2차원 영상에서 돌출부위를 포함시킬 때의 p-value는 0.005인 반면 포함하지 않을 때의 p-value는 0.057로 나타났다. 돌출형 전립선의 부피측정은 돌출부위를 제외하고 상하길이를 측정하는 것이 3차원 볼륨 렌더링에 의한 부피 값과 더 가까운 부피 값을 얻을 수 있었다. This study is to compare the accuracy of evaluation regarding the volume of the prostate, which three-dimensional volume rendering was produced the shape of protrusion, by measuring two kinds of craniocaudal length from the top of the protrusion and from the exclusion of the protrusion as the starting points. For the imaginary protrusion prostate models, total of 10 models were roughly made by using devils-tongue jelly and changing each of the 10 ml of capacity from 10 ml to 100 ml. For the protrusion prostate models aimed at estimating the real volume, through 64 cannel computed tomography (CT) and 3.0 tesla magnetic resonance image (MRI) were conducted by planimetry technique from three-dimensional volume rendering. And then we performed to evaluate on significance of these volumes by wilcoxon signed rank test. Also the obtained volumes data by ellipsoid volume formula were measured the volume of protrusion prostate models two times with each method using the two kinds of craniocaudal length from top of the protrusion and from exclusion of the protrusion as the starting points. Finally, the significance of differences using wilcoxon signed rank test was evaluated between the real volume by planimetry technique and the measured volume by ellipsoid volume formula from three-dimensional volume rendering. The average of the protrusion length on the models was $0.90{\pm}0.18\;mm$ in CT and was $0.75{\pm}0.11\;mm$ in MRI. There were not statistically significant difference between MRI and CT from the volume of protrusion prostate models (p=0.414). In MRI (p=0.139) and CT (p=0.057), there were not statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from exclusion of the protrusion as the starting points. While, there were statistically significant difference between the real volume by planimetry technique and the measured volume by ellipsoid volume from top of the protrusion as the starting points in MRI (p=0.005) and CT (p=0.005). For the accurate measurement of the protrusion prostate models, the craniocaudal length of the prostate should be measured from the exclusion of the protrusion as the starting points.

보건계열 대학생의 취업역량강화 프로그램이 대학생활 적응과 학업성취도에 미치는 구조적 관계

성열훈,김성수,Seoung, Youl-Hun,Kim, Sung-Soo 한국디지털정책학회 2013 디지털융복합연구 Vol.11 No.2

본 연구는 보건계열 대학생을 대상으로 취업역량강화 프로그램 수행 후 만족도가 대학생활 적응과 학업성취도에 어떠한 영향이 있는지를 실증분석하기 위해 수행하였다. 충북 소재 1개 대학교의 보건계열 전공자를 대상으로 취업역량강화 프로그램 수행 후 만족도 및 대학생활 적응과 학업성취도를 자기기입식 설문조사를 통하여 수집하였다. 분석결과 취업역량강화 프로그램 만족도가 높을수록 대학생활 적응이 좋은 것으로 나타났으며, 높아진 대학생활 적응은 학업성취도에 영향을 미치게 됨을 알 수 있었다. 비록 취업역량강화 프로그램 만족도가 학업성취도에는 직접적인 영향관계가 없었으나 대학생활 적응을 통해 학업성취도가 높아져 향후 취업에도 긍정적인 영향이 있음을 시사한다. 대학 적응을 높이고 취업 활성화를 위한 환경 마련을 위해 학과 특성에 맞는 취업관련 프로그램을 활성화하는 적극적인 노력이 필요하다. The study conducted an employment capability reinforcement program targeting health-related college students, and then carried out positive analysis to find out how satisfaction affects adjustment to college life and academic achievement. An employment capability reinforcement program was conducted which targeted health related majors at a university located in Cheongbuk, and information on satisfaction, adjustment to college life, and academic achievement was collected through a self-administered questionnaire. The analysis results revealed that the higher the satisfaction for the employment capability reinforcement program, the better the adjustment to college life, while increased adjustment to college life affected academic achievement. Although the employment capability reinforcement program had no direct relationship of influence to academic achievement, the study shows that it does lead to increased academic achievement by way of adjustment to college life, which ends up as a positive affect for future employment. Therefore, active efforts are necessary to revitalize employment related programs that suit the characteristics of each department in order to establish an environment for revitalizing employment and increasing adjustment to college life.

미국 방사선사 면허제도와 기본 교육과정에 대한 고찰 : 텍사스주 일개 대학 사례를 중심으로

성열훈,Seoung, Youl-Hun 대한방사선과학회 2020 방사선기술과학 Vol. No.

The purpose of this study was to study on radiologic technologist's license system and primary pathway education curriculum in the United States American (USA), focused on one case of college in Texas. We were collected and analyzed through class participation at a community college in Tarrant, interviews with professors of radiologic science and clinical radiographers, field trips, an internet search, and literature reviews. As a result, first, the American radiologic technologists license system is composed of fifteen chapters, and the professional education courses for each field are being carried out through three courses of a primary pathway, a post primary pathway and a physician extender. Second, the primary pathway courses consisted the radiography, the radiation therapy, the nuclear medicine, the magnetic resonance imaging, the sonography. Third, the USA had about 30 times more clinical practice time than Korea. In clinical practice, students had done actually examination through X-ray exposure on patients. Last radiographers in the USA was able to perform intravenous injection of radiopharmaceutical agents on patient, so that he could perform rapid examination and efficient manpower operation. This study could be used as basic data for the globalization of radiologic technologists license system in Korea.

시뮬레이션 교육을 통한 일반 X선 검사의 오류 분석

성열훈 ( Youl-hun Seoung ) 한국방사선학회 2018 한국방사선학회 논문지 Vol.12 No.7

본 연구에서는 일반 X선 검사를 대상으로 시뮬레이션 교육 모델을 제시하고 실습 시 발생하는 오류를 분석하고자 하였다. 2012년부터 2018년까지 총 183명 (남자 77명, 여자 106명)의 학생이 참가하였다. 시뮬레이션 X선 시스템은 컴퓨터방사선영상(computed radiography, CR) 시스템을 이용하였다. 환자 보호, X선 검사의 정확성, 영상의 안정성 등의 검사 프로세스에 발생하는 오류 빈도수를 분석하였다. 그 결과 환자 자세 설정 오류, X선 중심선의 정확성 오류, 영상검출판의 크기 및 위치 설정 오류, 그리드 사용의 오류, 마킹의 오류, X선 조사조건 설정 오류, 조사야 설정의 오류, X선 입사각도의 오류, X선 조사거리의 오류 순으로 분석되었다. 이러한 오류를 중심으로 개선된 방사선사 실습 교육이 필요할 것이며 그로 인하여 정밀한 검사와 고품질의 의료서비스를 제공하여 국민들의 보건의료에 조금이나마 기여할 수 있기를 기대한다. The purpose of this study was to present simulation training model for general X-ray examinations and to analyze the errors that occur during the simulation training. From 2012 to 2018, a total of 183 students (77 men and 106 women) participated. The simulated X-ray system used computed radiography (CR) system. The contents of simulation training were patient’s care, X-ray examinations accuracy, images stability, etc. As a result, it were found that the patient's position setting error, the accuracy error of the X-ray beam central ray, the image receptor’s size and setting error, the error of the grid use, the marking error, and the error of X-ray exposure technical factors. It is expected that improved practical general X-ray examinations training of radiographer will be needed, focusing on these errors, so that we could contribute to the health care of the people by providing precise examinations and high quality medical service.

전산화단층영상을 이용한 그물형 손목 부목의 3D 프린팅

성열훈(Youl-Hun Seoung) 한국콘텐츠학회 2015 한국콘텐츠학회논문지 Vol.15 No.1

본 연구는 3D 프린터를 이용하여 통풍이 원활하고 위생적이며 선명한 방사선영상을 구할 수 있는 그물형 손목 부목을 제작하고자 하였다. 스캐너는 의료용 다중단층영상장치(MDCT)를 이용했으며, 3D 프린터 기기는 용융 적층 조형술(fused deposition modeling, FDM)의 프린팅 방식을 이용했다. 소재는 분해성 플라스틱 (poly lactic acid, PLA)을 사용하였다. 손목의 3 차원 볼륨렌더링은 MDCT에서 획득된 단층영상으로 구현하였다. 구현된 손목 3 차원 영상을 바탕으로 가상의 그물형 부목 모형을 디자인하고 출력하였다. 그 결과 3D 프린터로 출력된 부목이 기존 부목보다도 우수한 방사선 손목영상을 획득할 수 있었으며 가려움증 및 비위생적인 단점을 개선하고 부목 해체 작업이 용이하였다. 결론적으로 본 연구에서 모델링된 3D 부목 모형은 향후 3D 프린팅 부목 제작에 기초자료로 활용할 수 있으며 환자들의 실생활에 도움을 줄 것으로 기대한다. The purpose of this study, using 3D printer, was tried to fabricate the short arm cast of mesh types that can be hygienic and adequate ventilation with a good radiography. We used the multi channel computed tomography (MDCT) with three dimension printer device of the fused deposition modeling (FDM) techniques. The material is used a degradable plastic (poly lactic acid, PLA). Three-dimensional images of the short arm were obtained in the MDCT and then make the three-dimensional volume rendering. Three dimension volume rendering of the short arm is implemented as a tomography obtained in MDCT. Virtual mesh type cast model was output as three-dimensional images is designed based on the three-dimensional images of the short arm. As a results, the cast output by 3D printers were able to obtain excellent radiograph images than the conventional cast, and then it can decreased itching with unsanitary, and can break down easily to the cast. In conclusion, the proposed virtual mesh type cast output by 3D printers could be used as a basis for future three-dimensional printing cast productions and offered help to patients in the real life.

미국 방사선사 면허제도와 기본 교육과정에 대한 고찰 : 텍사스주 일개 대학 사례를 중심으로

성열훈(Seoung Youl-Hun) 대한방사선과학회(구 대한방사선기술학회) 2020 방사선기술과학 Vol. No.

The purpose of this study was to study on radiologic technologist‘s license system and primary pathway education curriculum in the United States American (USA), focused on one case of college in Texas. We were collected and analyzed through class participation at a community college in Tarrant, interviews with professors of radiologic science and clinical radiographers, field trips, an internet search, and literature reviews. As a result, first, the American radiologic technologists license system is composed of fifteen chapters, and the professional education courses for each field are being carried out through three courses of a primary pathway, a post primary pathway and a physician extender. Second, the primary pathway courses consisted the radiography, the radiation therapy, the nuclear medicine, the magnetic resonance imaging, the sonography. Third, the USA had about 30 times more clinical practice time than Korea. In clinical practice, students had done actually examination through X-ray exposure on patients. Last radiographers in the USA was able to perform intravenous injection of radiopharmaceutical agents on patient, so that he could perform rapid examination and efficient manpower operation. This study could be used as basic data for the globalization of radiologic technologists license system in Korea.

ABS 수지의 용융적층조형방식에 의한 자가 맞춤형 부목의 3차원 출력 사례 연구

성열훈(Seoung, Youl-Hun) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.9

본 연구에서는 소량생산 및 개인 맞춤형 제작으로 매우 유용한 3D 프린팅 기술을 이용하여 자가 맞춤형 부목을 제작하고자 하였다. 방법으로는 3D 프린터를 이용하여 용융적층조형방식(fused deposition modeling)으로 부목을 제작하였으 며, 재료는 열가소성 플라스틱 계열인 ABS(acrylonitrile butadiene styrene) 수지를 이용하였다. 부목의 모델링은 실제 인체의 손 부위 3차원 전산화단층영상을 이용하였으며 통풍이 가능하도록 설계하였다. 그 결과 실제 인체 손 모양과 일치하는 자기 맞춤형 부목이 성공적으로 출력되었다. 또한 기존 부목보다도 우수한 방사선영상을 획득할 수 있었다. 결론적으로 본 연구에 서 제시한 3D 프린팅 사례는 ABS 수지를 이용한 용융적층조형방식의 유사한 구조물을 출력할 때 기초자료로 사용할 것으로 판단된다. In this study, we have tried to use 3D-printing technology, which is very useful for small amount production and individual personalization manufacturing to produce a cast customized by individual. To do this, we have made casts by the 3D printer in the method of fused deposition modeling technique using ABS(acrylonitrile butadiene styrene) resin which is thermoplastic plastics. The computed tomography of human hand part was used as the modeling of the cast and it was designed to circulate air well. As a result, an individual personalized cast that fitted well with the model part was produced. In addition, we could get more excellent radiography from the cast than the existing cast. In conclusion, this study of 3D-printing could be used as basic data when a similar designed structure in fused deposition modeling technique by ABS resin is printed out.