대퇴동맥지혈 기구(compression device)의 유용성에 대한 연구

조인완,조재환,이의현,구상진,김영수,유병헌,김승식 대한인터벤션영상기술학회 2003 대한인터벤션영상기술학회지 Vol.6 No.2

Project Management -Management of Mushroom factory construction-

조인완,김진우,한재용,노동호 한국산업경영시스템학회 2011 한국산업경영시스템학회 학술대회 Vol.2011 No.춘계

위암의 병변부위의 입체적 정보제공을 위한 Ray-sum 기법의 활용

조인완(In Wan CHO),강성진(Sung Jin KANG),안수현(Soo Hyun AHN),유병헌(Byung Hun YOO),김승식(Seung Sik KIM) 대한CT영상기술학회 2005 대한CT영상기술학회지 Vol.7 No.1

Purpose To Provide the three dimensional image of gastric cancer for pre operation planning of extent of resection margin by Ray-sum technique. Material & Method 34 cases(male 27, female 7) of pathologically proven stomach cancer are included in this examination during Oct. 2004~Jan. 2005. All patients were fasting state during 8 hours, and N injected buscopan 20min, before examination. On the table, they ingested 2 packs of gas forming agent and took the images on the supine position. Imaging examinations were performed with Somatom Sensation 16(Siemens, Erlangen, Germany) CT scanner with 0.75mm collimation, 5mm thickness, 9mm/sec table feed and the images were reconstructed with 1mm thickness and 0.7mm increments. Then we made Ray-sum images by using Wizard (Siemens, Erlangen, Germany) with -400~-1024 threshold, 30% of penetration and 85% brightness. Finally images were analysed by radiologist without knowledge about patients as 4grades(Excellent, Good, Fair, Poor). Result Among 34 cases, early gastric cancer is 17, advanced gastric cancer is 12 and others are 5 cases. 8cases of early gastric cancer and 11 cases of advanced gastric cancer are detected on the Ray-sum images and graded Excellent is 1, Good is 2, Fair is 4 and Poor is 1 case in early gastric cancer and Excellent is 7, Good is 3, Fair is 1 and Poor is 0 case in advanced gastric cancer. As result, the sensitivity of Ray-sum images is 47% of early gastric cancer and 91.6% of advanced gastric cancer. Conclusion CT Ray-sum technique is useful tool for surgical operation plan of gastric cancer patients. And this technique maybe replaced with U.G.I

Comparative Analysis and Usefulness by Quantitative Evaluation of Deep Learning Image Reconstruction and Adaptive Statistical Iterative Reconstruction-V in Aortic Vessels CT

고창수(Chang-Su Ko),조인완(In-Wan Cho),강지원(Ji-Won Kang),정우준(Woo-Jun Jeong),송훈(Hoon Song) 대한CT영상기술학회 2021 대한CT영상기술학회지 Vol.23 No.2

기존의 ASIR-V 기법과 DLIR 기법을 이용하여 영상을 재구성한 후, 정량적 비교평가를 통한 DLIR 기법의 유용성에 대하여 확인해 보고자 한다. Phantom을 이용하여 구조적 유사지수(SSIM), 신호 대 잡음비(SNR)와 대조도 대 잡음비(CNR)을 비교분석하였다. 또한 대동맥 혈관 CT(AVCT) 검사를 진행한 환자들의 영상을 바탕으로 Phantom과 동일한 방법으로 SNR과 CNR을 비교분석 하였다. 측정된 SSIM 값은 두 기법간의 영상을 서로 비교한 평균 값에서 TF와 SSIM 값이 높게 측정 되었다. Phantom을 이용한 SNR 측정값을 토대로 한 두 기법 간의 통계적 유의성 검증 결과 모든 플러그에서 통계적으로 유의한 결과를 보였다.(p<0.05) CNR 측정값을 토대로 한 통계적 유의성 검증 결과에서는 TF-H와 ASIR-90%의 Brain 플러그에서는 통계적으로 유의한 수준을 나타내지 않았으며,(p>0.05) 그 외 다른 플러그에서는 통계적으로 유의한 결과를 보였다.(p<0.05) AVCT를 검사를 진행한 환자들의 조영 전과 조영 후 영상에서의 SNR값은 통계적으로 유의한 결과를 보였다.(p<0.05) CNR값의 통계적 유의성은 조영 전 영상에서는 하행 대동맥 측정영역에서만 통계적으로 유의한 결과를 보이지 않았으며,(p>0.05) 나머지 부위에서는 통계적으로 유의한 수준을 나타냈다.(p<0.05) 조영 후 영상에서는 모든 관심 부위에서 통계적으로 유의한 결과를 보였다.(p<0.05) DLIR 기법은 영상의학과 판독의와 임상의에게 정확한 진단을 결정하는데 많은 도움을 줄 수 있으며 AVCT검사에서 기존의 영상 재구성 기법에 비해 보다 나은 최적의 영상을 획득할 수 있는 재구성 기법으로 충분한 가치가 있다고 사료된다. We studied that how the Deep Learning Image Reconstruction(DLIR) technique was useful through comparative evaluation after reconstructing the images by conventional ASIR-V technique and DLIR technique. We measured SSIM with PBU-60 Phantom and compared SNR and CNR by the each tissue equivalent material, using Tomotherapy Cheese Phantom. Also SNR and CNR were compared in the same way with phantoms, using the patients’ aortic vessels CT images. As a result of comparing average of SSIM from the images reconstructed by ASIR-V technique and True-Fidelity(TF) images which were reconstructed by DLIR, the average of SSIM from TF was higher than the average of SSIM from ASIR-V. In the using Phantom the result that based on SNR between two techniques had statistical significance.(p<0.05) The result that based on CNR was significant statistically in all the plugs except for the case of CNR from TF-H and ASIR 90% at the plug of brain. SNR result, there was statistical significance between the two techniques(p<0.05) in both cases of pre and post enhanced AVCT images from the patients. At the pre-enhanced images, CNR from every part had significant result statistically except for the part of descending aorta from TF-H and ASIR-90%. However, there was statistical significance in the post-enhanced images of every ROI.(p<0.05) DLIR technique help the radiologist and the clinicians diagnose the diseases accurately. Compared to the conventional technique reconstructing the images in AVCT, it would be good enough to get much more high-quality images.

고밀도 물질에 기인한 CT영상 화질저하 개선을 위한 Iterative MAR 알고리즘 적용의 유용성에 관한 연구

강지원(Ji Won Kang),조인완(In Hwan Jo),김현주(Hyeun Joo Kim),정우준(Woo Joon Jeong),고병근(Byeung Geun Go),이정탁(Jeong Tak Lee),유회성(Hoi Seong Yoo),유병헌(Byeong Heon Yoo) 대한CT영상기술학회 2016 대한CT영상기술학회지 Vol.18 No.2

Purpose: In this research we tried to know the limitation and how much IMAR algorithm useful is in the clinical field by the evaluation of image and ana lysis using image data from phatom research and clinical research which used the Iterative MAR(Metal Artifact Reduction) algorithm from Inc. C that chose the way to get the data through its own HU of the kinds of metal in the human body(Titanium:4.5g/cm³ Around 6500HU, Stainless steel:7.8g/cm³ Around 50000HU, Gold:19.3g/cm³ Over 100000HU). Materials and Methods : We made the phantom with the dense material used in the replacement arthroplasty(L-spine : Titanium, Hip joint : Stainless steel), made of platinum for aneurysm in cerebral vessels and gold for dental filling. Also we used these machines, Somatom Derinition Flash from Inc. 5 and 64-MDCT Discovery 750 HD from Inc. G. we had studied from 1st May to 31st Oct. in 2015 using the image data from the patients to visit the hospital for f/u test. We used Advantage workstation program for alnalysis. We chose the ROI sized 2mm at the same part of Black Streak artifact and White streak artifact to record the average of the CT value after measuring it 20 times. Calculating the attenuation number, using the CT value measured, we calculate the attenuation number for each machines as the percentage to know how much the attenuation decrease, then compared and analyzed that. We got the image data after scan and set the same WW/WL of image data through Advantage Workstation program for research about clinical image. After then two groups, one consists of 2 radiologists and another one consists of 3 radiology technicians, evaluate how much the artifact reduce and the factors deciding the image quality such as resoultion and contrast. Result : As a result of converting attenuation coefficient into a percentage in the phantom research, Black streak artifact and White streak artifact of GDC coil image with MAR algorithm were 94% and 51% but both of them of GDC coil image with IMAR algorithm were 1% and 37%. Both of them decreased by 93% and 14% each. In Titanium, Black streak artifact decreased by 6%, from 17% to 11% and White streak artifact decreased by 19%, from 21% to 2% after using IMAR algorithm instead of MAR. In stainless steel Black streak artifact decreased by 5%, from 7% to 2% and White streak artifact decreased by 27%, from 34% to 7%. According to this phantom research, GDC coil, titanitum, and stainless steel are evaluated ‘adequate’ which had 3points in most of categories. Gold is the only one evaluated ‘good’ which had 4points in most of categories. This is the result of using IMAR algorithm instead of WFBP in the clinical image research, after converting attenuation coefficient into a percentage. Black streak artifact decreased by 17%, from 24% to 7%, and White streak artifact decreased by 7%, from 9% to 2% in plantium(GDC coil). In gold for dental filling, Black streak artifact decreased by 23%, from 33% to 10%, and White streak artifact decreased by 25%, from 30% to 5%. Also in stainless steel, Black streak artifact decreased by 48%, from 52% to4%, and White streak artifact decreased by 45%, from 46% to 1%. According to the evlauation for clinical images, GDC coil, titanium, and Stainless got 4points which meant ‘good’ in most of categories. Gold evaluated ‘adequate’, 3points in most of categories. Condusion : IMAR algorithm is more useful to reduce metal artifact caused by dense material rather than MAR algorithm. Using IMAR algorithm can provide information of various kinds to tissue with less artifact around metal foreign body, so it will be much more helpful for accurate diagnois. 목적 : 본 연구에서 인체에 삽입된 금속의 물질별(Titanium :4.5g/cm³ Around 6500HU, Stainless steel:7.8g/cm³ Around 5000HU, Gold:19.3g/cm³ Over 100000HU)로 고유의 HU(Hounsfield Unit)값을 적용하여 Data를 얻는 방식인 S사의 Iterative MAR(Metal Artifact Reduction) 알고리즘을 팬텀 연구와 임상 연구를 시행하여 획득된 영상데이터를 이용하여 정량적 분석과 임상 영상평가를 통하여 IMAR 알고리즘 유용성과 더불어 제한점을 알아보고자 하였다. 대상 및 방법 : 임상에서 치료목적으로 사용하는 재료 중 정형 외과적 치환술 시 이용하는 고밀도(L-spine: Titanium), (Hip joint: Stainless steel)물질과 머리 혈관 동맥류의 시술을 위해 사용하는 Platinum성분의 고밀도 물질인 GDC coil, 치아 충전재로 사용하는 Gold(Dental filling)를 이용하여 자체 제작한 팬텀과 이를 토대로 적용한 임상연구의 순으로 진행하였다. 연구를 위해 이용한 장비는 S사의 Somatom Definition Flash와 G사의 64-MDCT Discovery 750 HD를 사용하였다. 임상연구는 2015년 5월 1일부터 10월31일까지 5개월간 추적검사를 위해 내원한 환자의 영상데이터를 이용하였다. 정량적 분석은 Advantage workstation 프로그램에서 Black streak artifact와 White streak artifact의 동일한 부위에 직경 2mm의 ROI를 그려 CT value값을 20회 씩 측정 후 평균 CT value값을 기록 하였다. 측정 CT value 값을 이용하여 감약계수로 환산 후 각 장비별 인공물 감소 정도를 백분율로 계산 후 비교 분석 하였다. 임상영상 연구는 스캔 후 획득한 영상 Data를 Advantage Workstation 프로그램을 이용하여 WW/WL을 동일하게 설정 한 후 영상의학과 전문의 2명, 방사선사 3명 등 총 5명의 관찰자가 5점 척도로 인공물의 감소 정도 및 영상의 화질 좌우인자인 해상도 및 대조도 등의 항목을 적용하여 평가하였다, 결과 : 팬텀연구에서 감약계수를 백분율로 환산한 결과 GDC Coil에서 Black streak artifact와 White streak artifact순으로 MAR는 94%, 51%, IMAR는 1%, 37%로 93%, 14% 감소되었다. Gold에서 MAR는 30%, 22%, IMAR는 24%, 16%로 둘 모두 6% 감소되었다. Titanium에서 MAR는 17%, 21%, IMAR는 11%, 2%로 6%, 19% 감소되었다. Stainless steel에서 MAR는 7%, 34%, IMAR는 2%, 7%로 5%, 27% 감소되었다. 팬텀 영상 평가는 GDC coil, Titanium, Stainless steel 모두 Adquate(3점)이 가장 많았고, Gold는 Good(4점)이 가장 많았다. 임상 영상 연구에서는 감쇠계수를 백분율로 환산한 결과 Platinum(GDC Coil)에서 WFBP는 24%, 9%, IMAR는 7%, 2%로 17%, 7% 감소되었다. Gold(Dental filing)는 WFBP 33%, 30%, IMAR 10%, 5%로 23%, 25% 감소되었다. Titanium은 WFBP 93%, 61%, IMAR 35%, 15%로 58%, 46% 감소되었다. Stainless steel은 WFBP 52%, 46%, IMAR 4%, 1%로 48%, 45% 감소되었다. 임상 영상 평가는 GDC Coil, Titanium, Stainless steel 모두 Good(4점), Gold는 Adquate(3점)이 가장 많았다. 결론 : 고밀도 물질에 의한 Metal Artifact를 기존의 MAR Algorithm 보다 IMAR Algorithm을 적용시켰을 때 보다 유용하게 감소시킬 수 있으며. IMAR는 Artifact가 감소된 금속구조물주변의 다양한 조직들의 정보를 제공할 수 있어 영상의학과 판독의와 임상의에게 정확한 진단을 결정하는데 많은 도움을 줄 수 있을 것으로 사료된다.

요추 금속물 함유 환자의 조영증강 자기공명영상에서 감산(subtraction)기법의 유용성

강충환,주명식,서석근,조인완,김영수,김승식 대한자기공명기술학회 2004 대한자기공명기술학회지 Vol.14 No.-

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.

저관전압 흉부 CT검사 시 CT value의 변화에 따른 영상평가

김현주(Hyun Joo Kim),송훈(Hoon Song),조인완(In Wan Cho),안수현(Su Hyeon Ahn),신훈(Hoon Shin),유병헌(Byeong Heon Yoo),김승식(Seung Sik Kim) 대한CT영상기술학회 2007 대한CT영상기술학회지 Vol.9 No.1

Purpose Experiments carried out on the patients who visited this department for pulmonary disease and need CT scans for Follow-up to observe change of CT value, evaluation of image quality and decrease of radiation dose as change of tube voltage Materials and Methods Subjects were the patients of 20 persons visited this department for pulmonary disease and Somatom Sensation 16(Siemens, Erlangen, Germany) was used. Measurement of CT value as change cf tube voltage was done by setting up ROI diameter of 1cm at the height of thyroid, aortic arch, right pulmonary artery in arterial phase image using 100OkVp, measuring 3 times, and recorded the average. CT value of phantom was measured by scanning phantoms which means contrast media diluted by normal saline by various ratio with tube voltage of 80kVp, 100kVp, 120kVp, 140kVp and recorded the average of 3 CT values of center of phantom image. In analysing radiation dose, CTDIvol. values of the latest arterial phase image of 120kVp and as this research set that of 100kVp were analyzed comparatively. 2 observers graded quality of chest images by 5 degrees (UnaccepTable, Suboptimal, Adequate, Good, Excellent diagnostic quality). Results CT value of chest image increased at 100kVp by 14.06%~27.26% in each ROI than 120kVp. CT value of phantom increased as tube voltage lowered at various concentration of contrast media. CTDIbol. decreased at 100kVp(5.00mGy) by 36% than 120kVp(7.80mGy) in radiation dose analysis. here were 0 UnaccepTable, 1 Suboptimal, 3 Adequate, 10 Good, 6 Excellent diagnostic quality in totally 20 persons. Conclusion Chest CT scanning with low kilo-voltage for patients who need CT scan repeatedly can bring images valuable for diagnose, and decrease radiation dose against patients.

차별화된 예약 관리를 통한 방사선 검사 미 예약률 감소 방안

이종세,유병헌,유희옥,이근옥,강성진,조인완,이기협,유은정,홍정우 한국의료QA학회 2006 가을학술대회 Vol.2005 No.2

조영제 사용 환자에 대한 효율적 관리 방안

이은혜,장수한,백선화,강지원,오용운,송훈,박수인,조인완,박태현,김영수 한국의료QA학회 2009 가을학술대회 Vol.2009 No.2