Digital X-ray장비 구축 검진차량의 웹 기반 무선 네트워크 환경 구축 전과 후의 비교분석

류영환,권대철,구은회,동경래,최성현,장영일,Ryu, Young-Hwan,Kweon, Dae-Cheol,Goo, Eun-Hoe,Dong, Kyung-Rae,Choi, Sung-Hyun,Jang, Young-Ill 대한디지털의료영상학회 2010 대한디지털의료영상학회논문지 Vol.12 No.2

A total of 200 hospital employees participated in this study from January 2009 to June 2010. For the survey, each participant was given necessary items for external health exams. Cronbach's alpha was calculated for the survey regarding wireless networks. There was a need for educating data processing workers in the medical field regarding fundamental information prior to wireless network construction. The reason is high scores would be collected, which would reflect knowledge regarding data processing used at hospitals and the differences between paper charts and electronic charts. However, low scores were obtained which reflected knowledge regarding the differences between wired and wireless networks and Mini-PACS. Time for each patient was shortened to a maximum of three minutes and minimum of one minute for treatment and transmitting medical images when comparing pre and post wireless network construction(p < 0.01). Scores from the pre and post construction survey increase 1.98, 1.65, and 1.43 points for activity in the health screening area, usage of space in the health screening vehicle, and patient information storage respectively(p < 0.05). The number of patients receiving external health screenings twelve times was 3,655 prior to construction of a wireless network system. However, the number increased to 4,265 after construction. The increasing percentage was 17% in total. Prior to construction, X-ray images were taken 527 times, but after construction of a wireless network, this number growed to 1,194 and it was 116% increase. The loss of patient's medical treatment charts was reduced from 19.8% to 18.7% after construction. We believe that educating medical workers on Mini-PACS and Mini-OCS Systems will not only increase their efficiency but also make patients receiving better treatment.

Moyamoya 질환에서 1차 통과기법을 이용한 자기공명관류영상의 이해

류영환,구은회,정재은,동경래,최성현,이재승,Ryu, Young-Hwan,Goo, Eun-Hoe,Jung, Jae-Eun,Dong, Kyung-Rae,Choi, Sung-Hyun,Lee, Jae-Seung 대한디지털의료영상학회 2010 대한디지털의료영상학회논문지 Vol.12 No.1

The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.

국내 방사선사 인력 현황 분석

조재환 ( Jae Hwan Cho ),동경래 ( Kyung Rae Dong ),류영환 ( Young Hwan Ryu ),최성현 ( Sung Hyun Choi ),정재은 ( Jae Eun Jung ) 조선대학교 공학기술연구원 2012 공학기술논문지 Vol.5 No.1

The purpose of this study was to analyze the position of radiologist and understanding the demand of radiologist occupation. Data are collected in order to understand the demand of radiologist in the field of educational and medicine. As a result, radiation technician education program period can range from three to four years, including training facilities in the hospitals. The overall radiologist standard rate was 67.6%. The radiologist technician man power was increased, this number has increased by 1.71 % over the last 10 years. A survey was made for the manpower employment, Seoul occupied much with 23.83% and Kyonggi-do was 17.27%. The radiation technician occupies among the man power in the hospital was 3.7%. This manpower was less than Chinese medicine hospital that was 4.6%. The employment rate of radiologist was higher than the other graduate courses. Particularly, the radiologist was the highest in the hospital manpower population which indicates 0.8% radiologist among the total population of manpower in the hospital.

ALVIM Phantom을 이용한 화질관리

임득춘,동경래,박용순,김창복,류영환,Im, Deuk-Chun,Dong, Kyung-Rae,Park, Yong-Soon,Kim, Chang-Bok,Ryu, Young-Hwan 대한디지털의료영상학회 2009 대한디지털의료영상학회논문지 Vol.11 No.2

Among various physical or subjective assessments of the quality of X-ray images, physical assessments can be quantitative but they are eventually judged by the view of observers thus subjective assessments including the aspect of observers are required. The changes in the ability to detect lesions caused by changes in the thickness of acrylic plates were tested with the ROC interpretation method that has taken into consideration, all the features of physical assessments as well as observers' ability to observe and mental stages and even surrounding environments using an Alvim phantom and the result indicated that as the thickness of acrylic plates increased, the amount of noises occurred increased compared to signals and thus the ability to detect signals as well as the sensitivity that is an ability to signals accurately and the ability to distinguish noises from signals thus it is considered that more efforts of radiologic technologists will be required to detect small lesions of fat patients with diagnostic X-ray generating apparatus.

인터벤션에서 Calibration mode에 대한 오차율 비교

공창기(Chang gi Kong),류영환(Young hwan Ryu) 한국방사선학회 2020 한국방사선학회 논문지 Vol.14 No.5

이 연구의 목적은 경피적 혈관내 풍선 확장술이나 스텐트 삽입술에서 Balloon이나 Stent의 직경 및 길이를 예측 할 때 사용되는 정량적인 평가 도구인 Calibration Mode중 Catheter Calibration Mode, Auto Calibration Mode 그리고 Segment Calibration Mode에서의 오차율에 대해 알아보고자 하였다. Calibration의 정량적인 평가를 위해 정교하게 제작된 직경 × 길이(2 mm × 80 mm) Copper Wire와 5, 10, 15, 30, 40 mm의 Metal Ball을 이용하여 실험하였고, 아크릴 팬텀은 25 mm, 50 mm, 75mm, 100 mm, 125 mm, 150mm, 175 mm, 200 mm로 하여 각각의 높이에서 혈관조영 촬영장치로 Subtraction 영상을 획득하여 장비 회사에서 제공하는 소프트웨어인 Stenosis Analysis Tools을 이용하여 측정하였다. Catheter Calibration Mode에서의 오차율을 평가하기 위한 방법으로 Copper Wire를 각각의 아크릴 팬텀위에 올려놓고 촬영하였으며, Copper Wire 직경 2 mm를 Catheter의 직경으로 Setting하였고, 길이 8 mm Copper Wire의 길이를 Multi-segments로 측정하여 분석한 결과 1.13 ~ 5.63%의 오차율이 나타났다. Auto Calibration Mode에서의 오차율을 평가하기 위한 방법으로 각각의 아크릴 팬텀을 높이에서 아크릴 높이에 대한 수치를 입력하고, 8 mm Copper Wire의 길이를 Multi-segments 측정하여 분석한 결과 0 ~ 0.26%의 오차율이 나타났다. Segment Calibration Mode에서의 오차율을 평가하기 위한 방법으로 테이블 바닥에 있는 각각의 Metal Ball을 각각 Calibration하고, 각각의 아크릴 팬텀 위에 올려 있는 8 mm Copper Wire의 길이를 측정하여 아크릴 팬텀 높이 변화에 대한 8 mm Copper Wire 길이를 Mutli-segments 측정하여 분석한 결과 1.05 ~ 19.04%의 오차율이 나타났다. 그리고 Auto Calibration Mode에서 OID 변화에 대한 실험은 아크릴 팬텀의 높이는 100mm로 고정하고 OID만 450 mm ~ 600 mm로 변화를 하였을때 오차율은 0.13 ~ 0.38%로 나타났다. 결론적으로 소프트웨어에서 제공하는 정량적인 혈관의 치수평가를 하기 위한 이들 Calibration Mode 중 Auto Calibration Mode에서 높이 값을 입력하는 것이 오차율이 가장 적은 Calibration 방법임을 확인하였으며, Metal ball이나 기타 다른 물체를 이용하여 Calibration을 하기 위해서는 시술부위와 동등한 높이에 놓고 Calibration을 하는 방법이 오차율을 가장 줄일 수 있는 방법으로 사료된다. This study aimed to identify the error rates in Catheter Calibration Mode, Auto Calibration Mode, and Segment Calibration Mode among many calibration modes as a quantitative evaluation tool used for predicting the diameter and length of balloon or stent in percutaneous intravascular balloon dilatation or stent insertion. Our experiment was conducted with Copper Wire of 2 mm × 80 mm (diameter × length) manufactured elaborately for quantitative evaluation in calibration and Metal Ball of 5, 10, 15, 30, and 40 mm and Acryl Phantom of 25 mm, 50 mm, 75mm, 100 mm, 125 mm, 150mm, 175 mm, and 200 mm. At each height, subtraction images were acquired with a cineangiograph and Stenosis Analysis Tool as a software provided by the equipment company was used for measurement. To evaluate the error rates in Catheter Calibration Mode, Copper Wire was put on each acryl phantom before shooting. Copper Wire of 2 mm in diameter was set as a diameter for catheter, and Copper Wire of 8 mm in length was measured with Multi-segments. As a result, the error rates appeared at 1.13 ~ 5.63%. To evaluate the error rates in Auto Calibration Mode, the height of acryl was entered at each height of acryl phantom and the length of 8 mm Copper Wire was measured with Multi-segments and as a result, the error rates appeared at 0 ~ 0.26%. To evaluate the error rates in Segment Calibration Mode, each metal ball on the floor of table was calibrated and the length of 8 mm Copper Wire on each acryl phantom was measured and the length of 8 mm Copper Wire depending on the changes of acryl phantom height was measured with Mutli-segments and as a result, the error rates appeared at 1.05 ~ 19.04%. And in the experiment on OID changes in Auto Calibration Mode, the height of acryl phantom was fixed at 100mm and OID only changed within the range of 450 mm ~ 600 mm and as a result, the error rates appeared at 0.13 ~ 0.38%. In conclusion, it was found that entering the height values in Auto Calibration Mode, among these Calibration Modes for evaluating quantitative vascular dimensions provided by the software was the calibration method with the least error rates and it is thus considered that for calibration using a metal ball or other objects, putting them in the same height as that of treatment sites before calibrating is the method that can reduce the error rates the most.

진단용 엑스선 장치에 있어서 방사선 방어에 대한 일반 요구사항 -IEC 60601-1-3:2008에 근거한 KFDA DRS 1-1-3:2008-

강희두,동경래,권대철,최준구,정재호,정재은,류영환,Kang, Hee-Doo,Dong, Kyung-Rae,Kweon, Dae-Cheol,Choi, Jun-Gu,Jeong, Jae-Ho,Jung, Jae-Eun,Ryu, Young-Hwan 대한디지털의료영상학회 2009 대한디지털의료영상학회논문지 Vol.11 No.2

This study gives an account of the collateral standards in IEC 60601-1-3: 2008 specifying the general requirements for basic safety and essential performance of diagnostic X-ray equipment regarding radiation protection as it pertains to the production of X-rays. The collateral standards establish general requirements for safety regarding ionization radiation in diagnostic radiation systems and describe a verifiable evaluation method of suitable requirements regarding control over the lowest possible dose equivalent for patients, radiologic technologists, and others. The particular standards for each equipment can be determined by the general requirements in the collateral standard and the particular standard is followed in the risk management file. The guidelines for radiation safety of diagnostic radiation systems is written up in ISO 13485, ISO 14971, IEC 60601-1-3(2002)1st edition, medical electric equipment part 1-3, and the general requirements for safety-collateral standards: programmable electrical medical systems. Therefore the diagnostic radiation system protects citizens' health rights with the establishment and revisions of laws and standards for diagnostic radiation systems as a background for the general requirements of radiation safe guards applies, as an international trend, standards regarding the medical radiation safety management. The diagnostic radiation system will also assure competitive power through a conforming evaluation unifying the differing standards, technical specifications, and recognized processes.

뇌파검사실의 배경조명에 따른 광자극의 영향

허재석 ( Jae Seok Heo ),최완수 ( Wan Soo Choi ),배난영 ( Nan Yeong Bae ),류영환 ( Young Hwan Ryu ),동경래 ( Kyung Rae Dong ),여화연 ( Hwa Yeon Yeo ) 조선대학교 공학기술연구원 2014 공학기술논문지 Vol.7 No.2

뇌파검사는 오래전부터 뇌의 기능을 평가할 수 있는 검사로 널리 이용되고 있다. 광자극은 뇌파검사 중 간단하게 비정상적인 파형을 유발 할 수 있어 뇌파 검사에서 기본적으로 사용되는 유발법이다. 일반적으로 뇌파검사는 전기적 차폐, 소음, 조명등 조건이 잘 갖추어져 있는 검사실에서 진행되지만 왕진뇌파의 경우 중환자실, 응급실, 병동 등 조건이 충분하지 않은 곳에서 진행 되어지는 경우가 많다. 특히 광자극의 경우 검사실의 조명을 어둡게 하라고 권유하고 있지만 왕진뇌파는 이러한 조건을 충족 시킬 수 없는 경우가 많다. 따라서 본 저자는 뇌파검사 중 광자극에서 검사실 조명이 광자극 램프의 빛에 어떠한 영향이 있는지 실험을 하였다. 검사실의 조명을 밝게 한 상태와 완전히 소등한 상태에서의 조도계와 Spectrometer를 이용하여 광자극의 빛의 밝기, 강도, 파장, 색 온도, 색 좌표를 측정하여 비교하였다. 램프와 측정기의 거리는 유럽의 권고 기준에 따라 30 cm (nasion to lamp)로 하였으며, 광자극은 2, 5, 8, 10, 12, 15, 20, 25, 30 Hz를 선택하여 측정하였다. 검사실의 조명은 2쌍의 35W의 형광등이 총 5개가 설치가 되어있었다. 조도계를 이용하여 빛의 밝기를 측정해보니, 검사실 형광등의 조명밝기는 676 - 693 Lux으로 측정하면서 계속적으로 변화가 있었고, 암실의 상태에서는 0 Lux였다. 2 - 15 Hz까지는 두 조건에서는 결과의 차이가 있었으며, 25 Hz이상부터 그 차이는 거의 없었다. Spectrometer에서는 형광등에서의 빛의 강도는 암실에서 보다 더 높았으며, 빛의 파장을 측정한 결과 형광등의 파장의 간섭으로 인해 불규칙한 형태의 파장을 나타냈다. 또한 빛의 온도에는 형광등의 검사실이 더 높았으며, 빛의 색 좌표는 형광등이 암실보다 좌측에 위치한 것을 알 수 있었다. 이것은 암실에서의 빛이 형광등의 빛 보다 좀더 붉은색의 계열임을 알 수 있다. 암실조건의 광자극은 거의 같은 밝기가 측정되는 반면, 형광등 조건의 광자극은 그 밝기가 일정하지 않고 빛의 파장도 불규칙하다는 것을 조도계와 Spectrometer를 이용하여 확인을 할 수 있었으며 특히 빛의 밝기는 12 Hz에서 그 차이가 가장 많이 나타났다. 빛의 색 또한 암실이 더 빨간색에 가까워 형광등의 검사실 보다 더 유효하다는 것을 알 수 있었다. 이러한 결과를 볼 때, 뇌파검사 중 광자극은 검사실의 배경 밝기가 미세하지만 영향을 준다는 것을 알 수 있었으며, 검사자는 이것을 이해하여 검사 중 조명에 대해 더 신경을 써야 한다.

영상의학과 촬영실에서의 세균 오염도 측정에 관한 연구

동경래(Kyung Rae Dong),노상호(Sang Ho Ro),권대철(Dae Cheol Kweon),류영환(Young Hwan Ryu),동차분(Cha Bun Dong),유은영(Eun Yeong Yu),조영국(Young Kuk Cho) 한국실내환경학회 2009 한국실내환경학회지 Vol.6 No.4

Since equipment currently being used in the department of radiological technology in hospitals comes into contact with patients carrying diseases, there inevitably will be the existence of pathogenic bacteria. Therefore, in order to increase the importance of using disinfectant in hospital infection precaution and the recognition of hospital infection management, comparisons were made by measuring the bacterial contamination levels in radiology room within the department of radiological technology and comparing the measurements with post disinfection levels. Disinfecting the rooms from detected bacteria was conducted with water, tissue cleaner, or 70% alcohol. When measuring bacterial contamination levels in radiology rooms, a variety of bacteria was detected. When disinfecting the interior of radiology rooms the effectiveness of destroying bacteria and preventing hospital infection was greatest when using 70% alcohol compared to water, tissue cleaner and ventilation. Therefore, there needs to be a development of a better antiseptic for destroying bacteria because there is a possibility for hospital medical equipment to be constantly contaminated. Efforts need to be made to prevent hospital infections and patient secondary infection by disinfecting and sterilizing equipment.

골밀도 측정의 정확한 정도관리방법

김호성(Ho-Sung Kim),동경래(Kyung-Rae Dong),류영환(Young-Hwan Ryu) 대한방사선과학회(구 대한방사선기술학회) 2009 방사선기술과학 Vol.32 No.4

골밀도의 질 관리는 검사를 시행하는 방사선사들의 책임과 의무이다. 하지만 질 관리의 이해 부족과 방법의 무지로 인한 잘못된 결과는 환자에게 치명적인 오류를 범할 수 있다. 따라서 이 논문은 올바른 질 관리의 이해와 방법을 기술하여 검사자 및 환자, 의뢰의사에게 골밀도 검사의 신뢰성을 확보하는 것을 목적으로 한다. 이중 에너지 엑스선 골밀도 기기(dual energy X-ray absorptiometry, DXA)는 골밀도 측정은 정확도와 정밀도가 우수하여야 작은 골량의 변화에도 진정한 생물학적 변화를 알 수 있다. 따라서 정확도와 정밀도를 높이기 위한 수단으로 장비 및 검사자의 올바른 질 관리가 지속적으로 이루어져야 한다. 올바른 장비관리방법은 매일 아침 장비 보정 질 관리 후 제조사에서 권고하는 팬텀을 이용하여 10~25회 측정하여 평균값을 구하고 이를 기준 으로 허용 범위(±1.5%)를 지정한다. 팬텀의 측정은 검사가 있는 날에 매일 측정하거나 일주일에 3회 이상 측정하여 실제 골밀도의 값의 변화 유무를 확인하여야 한다. 또한 측정된 팬텀의 골밀도 수치를 기록 한 Shewart control chart를 Rule에 따라 평가한다. 이러한 관리는 장비의 설치 및 이동 시에 반드시 행해져야 한다. 검사자 관리방법은 정밀도 측정으로 평가하는데 정밀도는 재검사하였을 때에 실제 생물학적 변화 없이 수치상의 결과 값을 똑같이 재현될 수 있는지 알아보는 것이다. 측정 방법은 골밀도 검사를 진행하면서 환자를 두 번씩 30번 측정하는 방법과 세 번씩 15번 측정하는 방법이 있다. 측정에서 중요한 것은 한 번 검사 후 두 번째나 세 번째 검사에서도 반드시 검사 테이블에서 내려왔다 다시 올라가서 검사를 해야 한다. 측정된 골밀도수치로 정밀오차를 산출하고 95% 신뢰수준으로 정밀오차에 2.77을 곱하여 최소한의 생물학적 골밀도 변화를 산출한다. 산출된 값을 최소한의 의미있는 변화라고 표현하며 이 값을 넘어섰을 경우가 진정한 생물학적 변화구간이라고 할 수 있다. 검사자의 정도관리는 처음 검사를 시작하는 경우와 장비의 이동 및 교체 시에 반드시 행해져야하며 지속적으로 이루어져야 한다. 골밀도 검사를 시행하는 방사선사의 올바른 질 관리의 수행은 장비의 수명 연장과 정확한 결과의 산출로 이어져 검사의 신뢰성 확보와 환자 및 방사선사에게 부적절한 검사로 인한 방사능 노출의 최소화에 도움을 줄 것이다. The image quality management of bone mineral density is the responsibility and duty of radiologists who carry out examinations. However, inaccurate conclusions due to lack of understanding and ignorance regarding the methodology of image quality management can be a fatal error to the patient. Therefore, objective of this paper is to understand proper image quality management and enumerate methods for examiners and patients, thereby ensuring the reliability of bone mineral density exams. The accuracy and precision of bone mineral density measurements must be at the highest lever so that actual biological changes can be detected with even slight changes in bone mineral density. Accuracy and precision should be continuously preserved for image quality of machines. Those factors will contribute to ensure the reliability in bone mineral density exams. Proper equipment management or control methods are set with correcting equipment each morning and after image quality management, a phantom, recommended from the manufacturer, is used for ten to twenty-five measurements in search of a mean value with a permissible range of ±1.5% set as standard. There needs to be daily measurement inspections on the phantom or at least inspections three times a week in order to confirm the existence or nonexistence of changes in values in actual bone mineral density. in addition, bone mineral density measurements were evaluated and recorded following the rules of Shewhart control chart. This type of management has to be conducted for the installation and movement of equipment. For the management methods of inspectors, evaluation of the measurement precision was conducted by testing the reproducibility of the exact same figures without any real biological changes occurring during reinspection. Bone mineral density inspection was applied as the measurement method for patients either taking two measurements thirty times or three measurements fifteen times. An important point when taking measurements was after a measurement whether it was the second or third examination, it was required to descend from the table and then reascend. With a 95% confidence level, the precision error produced from the measurement bone mineral figures came to 2.77 times the minimum of the biological bone mineral density change. The value produced can be stated as the least significant change (LSC) and in the case the value is greater, it can be started as a section of genuine biological change. From the initial inspection to equipment moving and shifter, management must be carried out and continued in order to achieve the effects. The enforcement of proper quality control of radiologists performing bone mineral density inspections which brings about the durability extensions of equipment and accurate results of calculations will help the assurance of reliable inspections.