림프관 조영술 시 리피오돌의 가온에 관한 고찰

강래욱(Rae-Wook Kang),김재석(Jae-Seok Kim) 한국방사선학회 2020 한국방사선학회 논문지 Vol.14 No.5

림프관 조영술에 사용하는 리피오돌의 온도에 따른 이동 속도 차이를 분석하여 검사의 효율성을 높이고 환자 및 시술자의 피폭선량을 감소하는 방안을 연구하였다. 0.014 inch Support Catheter에 Balloon Inflator를 이용하여, 일정한 압력으로 리피오돌을 주입하는 장치를 자체 제작한 후 Connecting Tube에 리피오돌을 충전하고 전열 기구를 이용 26 ℃, 36 ℃, 46 ℃의 온도로 주입과 동시에 Fluoroscopy를 촬영하였다. 리피오돌이 Support Catheter에서 20 cm 이동하는 시간을 측정하여 분석하였고, 통계적 유의성 확인 후 리피오돌을 적정 온도로 유지하는 방법을 고안하였다. 46 ℃ 환경에서 이동시간 평균은 11초, 36 ℃에서는 평균 13초, 26 ℃에서는 평균 17초 소요되었다. 리피오돌은 온도 상승에 따라 이동시간이 유의한 차이를 보였으며(p < .001), 온도가 높을수록 이동 속도가 빨라지는 것을 확인하였다. 림프관 조영술 시 상온에 노출된 리피오돌을 바로 주입하는 것보다 일정 온도로 가열하여 사용할 경우 주입속도를 높일 수 있는 동시에 림프관 안에서의 이동 속도를 향상할 수 있다. The study was conducted to improve the efficiency of the test and to reduce the exposure dose of patients and operators by analyzing the difference in the moving speed of Lipiodol according to the temperature during lymphography. The device for injecting Lipiodol at a constant pressure was self-made, and after inserting Lipiodol into the Connecting Tube, the moving speed of the contrast agent was photographed at temperatures of 26℃, 36℃, and 46℃ using a heat transfer device. Lipiodol movement time from the Support Catheter to 20cm was measured and analyzed, and statistical significance was confirmed. In the 46°C environment, the average moving time was 11 seconds, at 36°C the average was 13 seconds, and at 26°C the average was 17 seconds. Lipiodol showed a significant difference in moving time with increasing temperature (p<.001), and it was confirmed that the higher the temperature, the faster the moving speed. In the case of lymphangiography, when heated to a certain temperature (46 degrees) rather than injecting Lipiodol at room temperature, the injection speed can be increased and the speed of movement in the lymphatic vessel can be improved.

Usefulness Evaluation of Lower Extremity CT Angiography Examination using Heart Rate

김성식(Sung-Sik Kim),강래욱(Rae-Wook Kang),이임범(Im-Beom Lee),김재호(Jae-Ho Kim),박호성(Ho-Sung Park) 대한CT영상기술학회 2023 대한CT영상기술학회지 Vol.25 No.1

Lower Extremity CT Angiography 검사 시 환자의 심박동수에 따라 하지 혈관의 조영증강 차이를 비교 분석하여 최적화된 영상기법을 찾고 유용성을 평가하고자 한다. 2022년 1월부터 22년 8월까지 아주대병원을 내원하여 Lower Extremity CT Angiography검사를 진행한 외래환자 139명을 대상으로 하였으며, 심박동수에 따라 A(HR≤65), B(65<HR<80), C(80≤HR), 추가로 심박동수 65 이하의 환자들 중 Heart Rate를 고려하여 6초의 지연시간을 두고 스캔한 D 그룹으로 나누어 조영제 도달시간과 조영증강평균값을 비교 분석하였다. 결과는 SPSS 26 ver. 을 사용하여 분석하였다. 정량적 평가결과 Heart Rate가 65회 이상인 B, C그룹은 A 그룹에 비해 슬와 동맥의 HU 값이 우수하였으며, D 그룹은 A 그룹에 비하여 HU의 개선 효과를 보였다.(p<0.001) 심박동수의 차이는 하지 혈관 조영증강 강도에 영향을 주었다. 따라서 Lower Extremity CT Angiography 검사 시 심박동수를 활용하여 환자마다 적절한 검사 타이밍을 적용하는 것이 효과적이라 하겠다. The purpose of this study was to find an optimized imaging technique and evaluate its usefulness by comparing and analyzing the difference in contrast enhancement of lower extremity blood vessels according to the patient's heart rate during lower extremity angio CT examination. From January 2022 to August 22nd, 139 outpatients who visited Ajou University Hospital and underwent lower extremity angio CT examination were targeted. According to the heart rate, the groups were divided into four groups: A(HR≤65), B(65<HR<80), C(80≤HR). In addition, among patients with a heart rate of 65 or less, the heart rate was considered, and the scan was divided into group D with a delay time of 6 seconds. The time of arrival of contrast medium and the average value of contrast enhancement were compared and analyzed. The results were analyzed using SPSS 26 ver. As a result of quantitative evaluation, B and C groups with a heart rate of more than 65 times had better HU values in the popliteal artery than A group (HR≤65), and D group showed better HU improvement effects compared to A group (p<0.001). The difference in heart rate affected the angiographic intensity of the lower extremities artery. Therefore, it is effective to apply the appropriate test timing for each patient by using the heart rate during the lower extremity angio CT Scan.

선량감소효과를 위한 저관전압 복부CT의 추적검사에의 적용

안수현(Su Hyeon Ahn),조인완(In Wan Cho),강성진(Seong Jin Kang),강래욱(Rae Wook Kang),유병헌(Byeong Heon Yoo),김승식(Seung Sik Kim) 대한CT영상기술학회 2006 대한CT영상기술학회지 Vol.8 No.1

Purpose To study the analyse radiation dose, CT number, contrast scale, image quality of the patient who needs periodic follow-up examination by applying abdominal CT using low tube voltage. Materials & Methods To evaluate the image quality of abdomen, radiation dose, CT number and contrast scale follows in change of tube voltage, subjects are divided into two groups. One group is the patients able to be applied in the clinical analysis and the other group vvere used phantom. Somatom Sensation 16(Siemens, Erlangen, Germany) was used. Twenty patient were selected at random in the group which was applied periodic follow-up examination by CT. In this clinical study, tube current was fixed in 150mA, tube voltage was adjusted according to appropriate value of each examinations and then we measured CTDI values. The measurement of CT number of each organs was performed by setting up a lcm diameter ROI at abdominal organs in the same height of first lumbar vertebra by using images of arterial phase. Quality of the abdominal images were graded into the 3 degrees by two radiologists in consensus. Abdominal shaped acrylic phantom was used in phantom study. Ion chamber was inserted into the holes located on the center and periphery of the phantom, and around there, then scaned, and radiation dose were automatically displayed by the reader which were 80kVp, 100kVp, 120kVp, 140kVp of tube voltage were applied to the phantom(diluted contrast medium with water 1:10 ratio), then the phantom was scanned and a 1cm diameter ROI in the center of the image was measured CT number. Results CTDI value was m decreased in 100kVp by 36%(11.70mGy vs 7.50mGy) in comparison with 120kVp. According to radiologist’ evaluation, there were 17 equivalent, 3 acceptable, 0 unacceptable in the group of 20 subjects. Radiation dose in the phantom study showed decreasing as tube voltage was lowered from 80kVp to 140kVp. Peripheral dose decreased by 38%, and central dose decreased by 41%. CT number showed 1365.9±4.4HU in 80kVp, 1046.1±3.7 in 100kVp, 862.8±3.2HU in 120kVp, 737.5±3.0 in 140kVp. Conclusion By applying the low tube voltage using abdominal CT to the patients who need periodical follow-up examination, the quality of the image is relatively high contrast scale without a lowering of image quality and we can decrease the effect of radiation dose.

Ag-paste를 이용한 printed OTFT 제작 및 AMOLED 적용 연구

류기성(Gi-Seong Ryu),김현우(Hyun-Woo Kim),강래욱(Rae-Wook Kang),김영배(Young-Bae Kim),송정근(Chung-Kun Song) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.7

We fabricated OTFT by using Ag-paste for source and drains electrode of OTFTs on substrate. The OTFTs were fabricated by solution processes such as spin-coating for PVP gate dielectric and screen printingfor S/D electrodes with Ag-paste, except pentacene active layer which was deposited by evaporation. The mobility was 0.343±0.018 ㎠/V.sec and off state current ~10?¹¹ A and on/off current ratio ~10?. And than, we designed 16 × 16 pixels that each pixel was consisted of 2 OTFTs, 1Capacitor and 1 OLED.

완전 용액 공정으로 제작된 OTFT

안석근(Seok-Keun Ahn),김현우(Hyun-Woo Kim),강래욱(Rae-Wook Kang),송정근(Chung-Kun Song) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.7

The purpose of this paper is to report development of all-solution processed OTFTs using inkjet printing technique. The silver ink is used for gate, source and drain electrodes. We used poly-4 vinylphenol (PVP) for gate insulator and active layer is defined by using Bis (triisopropylsilylethynyl) pentacene (TIPS pentacene). The field effect mobility is 0.43㎠/Vs, on-off ratio is 7.1×10?.