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Forced suction thrombectomy in patients with acute ischemic stroke using the SOFIA Plus device
Roh Hyun Ki,Ju Min-Wook,Byoun Hyoung Soo,Park Bumsoo,Park Kwang Hyon,Jeongwook Lim 대한뇌혈관외과학회 2022 Journal of Cerebrovascular and Endovascular Neuros Vol.24 No.3
Objective: Stent retrieval thrombectomy has recently been the standard treatment for acute ischemic stroke with large artery occlusion. However, the development of catheters for suction thrombectomy has recently led to results comparable to that of stent retrieval thrombectomy (SRT). This study aimed to analyze the safety and efficacy of forced suction thrombectomy (FST) using the SOFIA Plus (MicroVention Terumo, Tustin, CA, USA) device.Methods: We included patients with acute ischemic stroke who underwent FST using the SOFIA Plus device at our institution. Medical records and angiographic data were reviewed, and the results of this study were compared with those of other FST studies.Results: A total of 35 patients were included in this study. The occlusion sites were the internal carotid artery terminal (4), M1 segment (20), and posterior circulation (11). Of the 35 patients, FST was performed in only 21 (60%) patients, and the remaining 14 (40%) patients underwent SRT and FST. In all cases, the recanalization rate was 100%, and the average time from groin puncture to recanalization was 21±4.94 min. In particular, the average time required to reach the SOFIA Plus lesions from the groin puncture was 10.44±5.06 min and about 67% of the FST patients were recanalized at the first attempt. Three-months modified Rankin Scale (mRS) score of ≤2 was observed in 52% of the patients.Conclusions: Forced suction thrombectomy using the SOFIA Plus yielded a high recanalization rate within a shorter time. In particular, the recanalization rate was higher than that reported in previous studies using other types of suction devices.
허혈성 심질환에 있어서 아데노신 급속 정맥투여후 관동맥압의 변화에 관한 연구
봉종대,오종용,배성한,신원용,김철현,이광희,최태명,현민수,김성구,권영주 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.2
Background: Adenosine interacts with A1 receptors present on the extracellular surface of cardiac cells, activating K+channels in a fashion. It produces coronary vasodilatation and AV nodal block. The half-time is one to six second and has ultra-short action. In ischemic heart disease, fractional flow reserve(FFR) can be achieved safely with intravenous adenosine infusions at a rate of 150㎍/kg/min which cause maximal coronary hyperemia. Purpose: We investigated the patients who have had ischemic heart disease(n=8). After adenosine intravenous administration(150㎍/kg/min), the effect cause maximal hyperemia of coronary artery. During peak maximal hyperemia, we reported clinical findings, coronary hemodynamics and electrocardiogram findings. Methods: After diagnostic coronary angiography and left ventriculography, catheter was advanced into the ostium of coronary artery. We investigated coronary hemodynamics such as systolic coronary artery pressure, diastolic coronary artery pressure, mean coronary artery pressure and heart rate. To assess the use of adenosine for determination of fractional flow reserve, hemodynamics and electrocardiogram were measured at basal state and during peak maximal hyperemia. Results: Symptoms developed 1.5-2 minute after adenosine intravenous administration and each symptom disappeared 2-2.5 minute after adenosine administration. Two patients represented asymptomatic appearance and six patients complained of flushing, chest pain, palpitation and headache. In eight patients with ischemic heart disease, 1.5 minute after venous administration of 150㎍/kg/min of adenosine, coronary artery pressure decreased and heart rate increased significantly. Conduction abnormalities after administration of 150㎍/kg/min of adenosine were transient 2nd degree AV block 2 cases(25%). Conclusions: Adenosine is a potent ultra short-acting vasodilator. Although coronary artery pressure decreased and heart rate increased and mild cardiovascular symptoms occurred after continuous infusion of 150㎍/kg/min of adenosine, it is useful as an agent for determination of fractional flow reserve.
현민수 순천향의학연구소 2004 Journal of Soonchunhyang Medical Science Vol.10 No.1
Magnetic resonance coronary angiography(MRCA) is an attractive test for the diagnosis of the coronary artery disease because it is noninvasive, does not require ionizing radiation or iodinated contrast media, can provide hemodynamic information in addition to vascular morphology, and can provide three-dimensional structural data. However MRCA is a more challenging task. The image aquisition takes time. The motion of the heart during the cardiac and respiratory cycles, the highly tortuous course and small size of the coronary artery, adjacent structures which have little image contrast with coronary arteries, and metallic devices that make artifacts hinder imaging process. The various imaging techniques need to be standardized. But MRCA is now using in the diagnosis of coronary artery anomaly, the evaluation of the patency after coronary artery bypass graft and the diagnosis of the coronary artery disease. The major challenges are to overcome the effects of the respiratory motion and to improve spacial resolution, signal-to-noise ratio, and consistency of imaging quality. With the recent substantial improvements in technique and further large multi-center trials, the clinical utility for MRCA would be expanded and MRCA will become an important part of a comprehensive coronary and cardiac examination.
2차 통계량을 이용한 도래 방향 추정 알고리즘의 성능평가
이민혁,노현민,정대훈,장은영,변건식 東亞大學校附設情報技術硏究所 2005 情報技術硏究所論文誌 Vol.12 No.2
it is needed high quality and big capacity according to fast supply of mobile communication medium. Therefore, adaptive array antenna is actively studied to supply demand. DOA(Direction of Arrival) estimation is important position in adaptive array antenna. The purpose of this paper is to estimate DOA. and compare with the existing algorithm.
데이터마이닝 기법을 이용한 문헌정보학 전문용어 클러스터링 모델의 데이터베이스 설계에 관한 연구
황정민,박미영,승현우 서울여자대학교 자연과학연구소 2002 자연과학연구논문집 Vol.14 No.-
Data mining, a relatively new technique which has been evolved from the field of the computer and information science, involves searching for patterns in data. Similarly, text mining involves searching for patterns in text. It may be defined as the process of analyzing text to extract information useful for a particular purpose. Text is relatively unstructured, amorphous and difficult to deal with, compared with other types of data stored in databases. The number of terminologies extracted from unstructured text documents is irregular and the terminologies themselves are general in nature, making it difficult to retrieve useful information as efficiently as using algorithms searching for general association rules. In this paper, we propose a database design method for the terminology clustering model in which a datamining technique is used in order to extract useful information from large documents. The proposed method can be used in various areas including automatic document classification and intelligent search engines.
연관규칙 데이터마이닝 기법을 이용한 전문 검색엔진 설계 및 구현
승현우,황정민,박미영 서울여자대학교 컴퓨터과학연구소 2003 정보기술논문지 Vol.1 No.-
본 논문에서는 검색엔진의 효율성을 높이기 위해서 연관규칙 데이터마이닝 기법을 이용한 전문 검색엔진을 설계 및 구현하였다. 연관규칙 탐사 기법인 Apriori 알고리즘을 이용하여 전문 용어별로 의미적으로 연관된 용어들을 클러스터로 구성해서 지식베이스 테이블을 구축하였다. 그리고 지식베이스 테이블을 이용하여 사용자가 제시한 키워드와 연관 정도가 높은 전문 용어를 포함한 문서를 검색하였다. 제안된 방법의 효율성을 검증하기 위하여 문헌정보학 전문 검색엔진을 구현하여 기존의 상용 검색엔진과 동일 키워드를 대상으로 검색 결과를 비교하였다. 비교 결과 기존의 검색엔진의 출력 결과보다 정확한 지식 정보를 포함한 문서를 효율적으로 검색할 수 있었다. In this research, we designed and implemented an expert search engine using the association rules which is one of the typical data mining techniques in order to enhance the efficiency of the search engine. First, we gathered technical terminologies and grouped them into clusters according to their association, and built a knowledge base. Second, using the knowledge base table, we tried to retrieve documents including terms highly associated with the keyword given by the user. In order to verify the efficiency of the proposed method, we constructed a search engine for the area of the library and information science, and compared it with the existing engines. As a result, we found the proposed engine search more accurate documents more efficiently than the existing engines.
황정민,승현우 서울여자대학교 자연과학연구소 2001 자연과학연구논문집 Vol.13 No.-
The world film industry, mainly led by the Hollywood, has been growing enormously for decades. The film industry in Korea is also at the height of its prosperity, owing to a series of recent box-office successes of blockbuster movies. Film producing or distributing companies in Korea are now investing an enormous amount of money fot eh film marketing. In order for them to capture movie-goers current interests rapidly and correctly, establish appropriate marketing strategies, and eventually succeed in the marketing, a new information infrastructure is needed. On the other hand, the data mining technology has been emerging and used in many application areas such as the decision support system, which helps find the unknown knowledge or regular patterns hidden in the database. In this paper, we design a data warehouse for the film information system which is known to be a good structure for data mining, and apply a various data mining techniques to the system.
골격성 제3급 부정교합환자의 하악지 시상분할 골절단술후 하안면 폭경 및 고경의 변화에 대한 두부계측 방사선학적 연구
장현석,임재석,권종진,이부규,손형민 대한악안면성형재건외과학회 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.3
Purpose : The purpose of this study was to analyze the lower third facial changes in frontal view after mandibular setback surgery. Materials and Methods : In this study, fifteen subjects(6 males and 9 females) with class III dental and skeletal malocclusions who were treated with BSSRO(Bilateral Sagittal Split Ramus Ostetomy) were used. Frontal cephalometric radiographs were taken preoperatively and more than 6 months postoperatively, and hard tissue(H2-Hl) and soft tissue changes (S2-S1) were measured on vertical and horizontal reference lines. In 15 cases, changes which developed more than 6 months after surgery were studied. Results : The results were as follows. 1.In the facial height, hard tissue decreased(2.46±2.76mm) with statistical significance(P<0.01), and soft tissue also decreased(1.64±3.66mm). As a result, the facial height generally becomes shorter after sagittal split ramus osteotomy. 2.In the mandibular width, hard tissue decreased(2.08±3.59mm) with statistical sgnificance(P<0.05), but soft tissue increased (2.14±5.73mm) without statistically significant difference (P>0.05) postoperatively. 3.In the facial index, hard tissue decreased(0.23±2.21%), but soft tissue increased(2.41±3.46%) with statistical significance. Conclusion : One of the main purpose of orthognathic surgery is to achieve facial esthetics and harmony. In order to fullfill this purpose, it is important to carry out a precise presurgical treatment planning by estimating the changes of frontal profile after surgery.
OFDM 시스템을 위한 Radix-8/4/2 FFT 프로세서
박정민,김영진,이현수 경희대학교 경희정보통신 SoC연구소 2008 경희정보통신SOC연구소 논문집 Vol.9 No.-
In this paper, we propose an efficient variable-length radix-8/4/2 FFT architecture for OFDM systems. The FFT processor is based on radix-8 FFT algorithm and also supports radix-4 or radix-2 FFT computation. A radix-8/4/2 butterfly unit computes radix-8 FFT algorithm basically. If it cannot run radix-8 FFT algorithm at last stage then it computes radix-4 or radix-2 FFT algorithm. Furthermore, proposed FFT architecture use shared-memory to minimize and simplify hardware. We are using efficient "In-place" memory access method to maintain conflict-free data access and minimize memory size. The design consider seven different FFT lengths including 64, 256, 512, 1024, 2048, 4096 and 8192 points which cover all the required FFT lengths by 802.11a, 802.16a. DAB, DVB-T, VDSL and ADSL.
배열 안테나를 사용한 디지털 비디오 방송용 OFDM 수신기의 성능평가
전제훈,노현민,변건식 東亞大學校附設 情報技術硏究所 2004 情報技術硏究所論文誌 Vol.12 No.1
Orthogonal frequency division multiplexing(OFDM) is becoming the chosen modulation technique for wire and wireless communications with fast data rate because of good spectral effciency and sufficient robustness of fading channel. Digital Video Broadcating is using OFDM to modulate. But Digital Video Broadcating has performance degradation in moving reception according to DOA(Direction of Arrival). The purpose of this paper is to improve reception performance using array antenna in environment with doppler effect.