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개의 심근경색 모델을 이용한 Flow Independent Dark Blood Delayed Enhancement 자기공명영상의 특성 평가
Full text link학위논문 (석사)-- 서울대학교 대학원 : 의학과, 2012. 8. 박재형.서론: 개의 심근경색 모델에서 새로운 지연기 조영증강 자기공명영상 기법인 Flow Independent Dark Blood Delayed Enhancement (FIDDLE)이 체외 고해상도 자기공명영상과 2,3,5-triphenyltetrazolium chloride (TTC)로 염색한 병리검체에서 확인된 심근경색 부위를 잘 보여줄 수 있는지 알아보고자 한다. 또한 기존의 고식적 지연기 조영증강 자기공명영상과 비교하였을 때 신호강도의 특성을 비교 분석하고자 한다.
방법: 혈관내 접착성 영구색전물질 (N-butyl-2-cyanoacrylate)을 이용하여 7마리 개의 좌측 관상동맥의 분지를 폐쇄하였다. 일 주일이 경과한 후 3-T 자기공명영상촬영기를 이용하여 모든 동물에서 고식적 지연기 조영증강 자기공명영상과 FIDDLE 자기공명영상을 조영제 주입 후 10분, 20분, 30분, 40분 후에 각각 촬영하였다. 2 마리의 개에서는 추가적으로 사후 체외 고해상도 자기공명영상과 TTC 염색을 시행하였다. 경색 심근, 정상 심근, 좌심실 내 혈액의 신호강도와 영상의 잡음(noise)를 두 기법 모두에서 각각 측정하였다. 이를 이용하여 경색 심근과 정상 심근, 경색 심근과 좌심실내 혈액 사이의 대조도대잡음비(contrast to noise ratio)를 각각 계산하고 서로 비교하였다. 또한 정성적으로 영상을 평가하여 병변 경계의 명확성, 심내막하 경색 부위가 눈에 띄는 정도(conspicuity), 그리고 정상 심근 신호강도의 균일성에 대해 점수를 부여하고 비교하였다.
결과: 두 기법 모두 7마리 실험동물 전부에서 심근경색 부위의 지연기 조영증강을 보여주었고 2마리에서는 자기공명영상에서 나타난 병변이 체외 자기공명영상과 TTC 염색 병리검체에서의 심근경색 병변과 일치함을 확인하였다. 경색 심근과 정상 심근 사이의 대조도대잡음비는 고식적 지연기 조영증강 자기공명영상이 FIDDLE보다 1.99배 높았으며 통계적으로 유의했으나(P=.018, 모두), 경색 심근과 좌심실내 혈액 사이의 대조도대잡음비는 FIDDLE이 2.12배 높았다. 그러나 통계적 유의성은 10분 지연기에서만 보였다(P=.028). 정성적 영상평가에서는 눈에 띄는 정도에서 FIDDLE이 우수하였으나 병변 경계의 명확성과 정상 심근의 균일도는 열등하였다.
결론: 체외 고해상도 자기공명영상과 TTC염색 병리소견을 이용하여 새로운 FIDDLE 기법이 위양성 조영증강 없이 경색 심근을 정확하게 보여주고 있음을 확인하였다. FIDDLE 기법은 심실 내 혈액의 신호강도를 효과적으로 억제함으로써 경색 심근과 좌심실 내 혈액 사이의 신호강도의 대조도를 높임으로써 심내막하 심근경색을 보다 민감하게 검출할 수 있을 것으로 기대된다.Purpose: To validate new magnetic resonance imaging (MRI) technique of Flow Independent Dark Blood Delayed Enhancement (FIDDLE) technique using ex-vivo imaging and 2,3,5-triphenyltetrazolium chloride (TTC) pathologic specimen and to compare signal intensities of infarcted myocardium over both blood cavity and remote normal myocardium in comparison with the conventional delayed enhancement cardiac MRI in a canine model of myocardial infarction.
Materials and Methods: Branches of left coronary arteries in seven dogs were occluded by endovascular glue (N-butyl-2-cyanoacrylate) injection. Contrast-enhanced MRI in a single short-axis slice was obtained at 3-T MRI scanner in all animals at 10, 20, 30, and 40 minutes after gadolinium administration using two different sequences of conventional delayed enhancement and FIDDLE a week after the modeling procedure. Ex-vivo MRI and TTC staining of the postmortem heart were performed in two animals. The signal intensities of the infarcted myocardium, normal myocardium and blood pool in left ventricular cavity and image noise was measured in two image datasets. Contrast-to-noise ratio (CNR) of the infarction to normal myocardium (CNRItoN) and that of infarction to blood pool (CNRItoB) for both image datasets were calculated and compared. Sharpness of infarction margin, conspicuity of subendocardial portion of the lesion, and homogeneity of normal myocardium were assessed qualitatively.
Results: Delayed enhancement of infarcted myocardium presented in both image datasets of all seven animals and was confirmed by ex-vivo MRI and TTC stained gross pathology in two animals. The mean values of CNRItoN were 1.99 times higher in conventional delayed enhancement images than in FIDDLE images with statistical significance (all, p=.018). On the other hand, mean values of CNRItoB were 2.12 times higher in FIDDLE than in conventional delayed enhancement images but statistical significance was seen only at 10 minutes after contrast injection (P=.028). In the qualitative study, FIDDLE images were superior for subendocardial lesion conspicuity but inferior for margin sharpness and homogeneity of normal myocardium.
Conclusions: Ex-vivo MRI and TTC staining confirmed that FIDDLE technique well depicted infarcted myocardium without false positive hyperenhancement. FIDDLE technique is expected to enable better detection of subendocardial infarction for its higher CNR of infarcted myocardium over blood cavity by nulling blood cavity signal effectively.Contents iii
Introduction 1
Materials and Methods 3
Results 8
Discussion 11
References 15
Abstract in Korean 17Maste
Novel Interventional Radiology for the Treatment of Various Lymphatic Leakages: Lymphatic Intervention and Embolization
No full textLittle progress has been made in modern lymphatic medicine since Dr. Kinmonth first described pedal lymphangiography in the 1950s. The clinical need for an effective treatment modality for managing lymphatic leakage greatly increased only after intranodal lymphangiography, which enabled the depiction of the exact location of the leakage. This review introduces five hypotheses that have been proposed while addressing various clinical scenarios involving lymphatic leakage: (1) various embolization techniques can be used to prevent lymphatic leakage; (2) lymph node embolization can treat postoperative pelvic lymphoceles that are refractory to sclerotherapy; (3) the technical success rate of thoracic duct cannulation can be improved by using retrograde thoracic duct access as a bail-out method; (4) non-traumatic chylothorax can be managed by understanding the underlying pathophysiology; and (5) chylous ascites can be managed by understanding the underlying pathophysiology. Five retrospective observational studies, one randomized prospective clinical trial, and two case reports (letters to the editor) were published after the hypotheses were validated. We provide a new systematic approach to lymphatic intervention by describing the process of the current comprehensive research
DEBvscTACE_supplement_20190516_clean – Supplemental material for Effectiveness of drug-eluting bead transarterial chemoembolization versus conventional transarterial chemoembolization for small hepatocellular carcinoma in Child-Pugh class A patients
No full textSupplemental material, DEBvscTACE_supplement_20190516_clean for Effectiveness of drug-eluting bead transarterial chemoembolization versus conventional transarterial chemoembolization for small hepatocellular carcinoma in Child-Pugh class A patients by In Joon Lee, Jeong-Hoon Lee, Yun Bin Lee, Yoon Jun Kim, Jung-Hwan Yoon, Yong Hu Yin, Myungsu Lee, Saebeom Hur, Hyo-Cheol Kim, Hwan Jun Jae and Jin Wook Chung in Therapeutic Advances in Medical Oncology</p
림프계 인터벤션과 색전술
Full text link학위논문(박사) -- 서울대학교대학원 : 의과대학 의학과, 2023. 8. 정진욱.1950년대 초반 Dr. Kinmonth가 발등 림프조영술을 도입한 이래 2000년 흉관색전술이 도입될 때까지 림프계에 대한 검사 및 시술법의 발전은 매우 더디었다. 2010년 대에 들어 림프절 경유 림프조영술을 통해 조영제를 효과적으로 주입하게 되면서, 영상검사를 통해서 각종 림프액 유출을 쉽게 관찰할 수 있게 되었다. 정확한 진단이 가능해지자, 비로소 효과적인 치료에 대한 임상적 요구가 생겨났다.
본 연구에서는 다양한 림프액 유출증에 대한 치료와 관련하여 다음의 6가지 가설을 세웠다.
① 액체 색전물질을 이용한 다양한 색전술 기법으로 손상된 림프관 또는 림프절로부터의 림프액 유출을 막을 수 있다.
② 림프절 색전술을 이용하여 경화술에 반응하지 않는 수술 후 골반 림프낭종을 치료할 수 있다.
③ 역방향 흉관 접근술의 보조를 받아 흉관색전술의 기술적 성공률을 향상할 수 있다.
④ 비외상 암죽가슴증의 병리기전을 이해하고 체계적으로 접근함으로써 치료할 수 있다.
⑤ 암죽 복수의 병리기전을 이해하고 체계적으로 접근함으로써 치료할 수 있다.
⑥ 일차 암죽 역류 질환의 병리기전을 이해하고 체계적으로 접근함으로써 치료할 수 있다.
6건의 후향 관찰연구 (5건 출판, 1건 구연 발표), 1건의 무작위배정 전향 임상시험 (출판), 2건의 증례보고(letter to the editor)를 종합적으로 기술함으로써, 림프계 인터벤션의 새로운 체계적 방법론을 제시하고자 한다.There had been little progress in the field of modern lymphatic medicine since Dr. Kinmonth described the first pedal lymphangiography in 1950s. Clinical needs of the effective treatment modality for the management of lymphatic leakages greatly increased only after the introduction of intranodal lymphangiography, which enabled to depict the exact location of the leakages. In this study, six different hypotheses were made to address various clinical scenarios involving lymphatic problems as follows.
① Various embolization techniques can stop lymphatic leakages
② Lymph node embolization can treat post-operative pelvic lymphoceles that are refractory to sclerotherapy
③ Technical success rate of thoracic duct cannulation can be improved by using retrograde thoracic duct access as a bail-out method
④ Non-traumatic chylothorax can be managed by understanding the underlying pathophysiology and being approached systematically
⑤ Chylous ascites can be managed by understanding the underlying pathophysiology and being approached systematically
⑥ Primary chylous reflux disease can be managed by understanding the underlying pathophysiology and being approached systematically
Six retrospective observation studies (5 of them were published in SCI journals and one was presented in Radiology Society of North America 2022), one randomized prospective clinical trial (published in 2023), and two case reports (letter to the editor) were performed during the validation of these hypothesis. We would like to provide a new systematic approach of lymphatic intervention by describing the process of the current comprehensive research.제 1 장 서 론 1
제 2 장 본 론 3
제 1 절 림프액 유출증에 대한 초기 색전술 시도 3
제 2 절 수술 후 골반 림프낭종에 대한 림프절 색전술 8
제 3 절 흉관색전술의 기술적 성공률 향상 14
제 4 절 비외상 암죽가슴증의 진단과 치료 19
제 5 절 암죽 복수의 진단과 치료 24
제 6 절 일차 암죽 역류 질환의 진단과 치료 33
제 3 장 결 론 39
참고문헌 40
Abstract 43
감사의 글 45
표 목차
[표 1] 12
[표 2] 17
[표 3] 36
그림 목차
[그림 1] 5
[그림 2] 6
[그림 3] 10
[그림 4] 15
[그림 5] 21
[그림 6] 22
[그림 7] 26
[그림 8] 27
[그림 9] 29
[그림 10] 35박
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
One-Year Outcomes of the Paclitaxel-Eluting Stent for TASC C and D Femoropopliteal Lesions in Real World
No full textDispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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