• Title/Summary/Keyword: Blood vessel

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Robust Ultrasound Multigate Blood Volume Flow Estimation

  • Zhang, Yi;Li, Jinkai;Liu, Xin;Liu, Dong Chyuan
    • Journal of Information Processing Systems
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    • v.15 no.4
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    • pp.820-832
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    • 2019
  • Estimation of accurate blood volume flow in ultrasound Doppler blood flow spectrograms is extremely important for clinical diagnostic purposes. Blood volume flow measurements require the assessment of both the velocity distribution and the cross-sectional area of the vessel. Unfortunately, the existing volume flow estimation algorithms by ultrasound lack the velocity space distribution information in cross-sections of a vessel and have the problems of low accuracy and poor stability. In this paper, a new robust ultrasound volume flow estimation method based on multigate (RMG) is proposed and the multigate technology provides detail information on the local velocity distribution. In this method, an accurate double iterative flow velocity estimation algorithm (DIV) is used to estimate the mean velocity and it has been tested on in vivo data from carotid. The results from experiments indicate a mean standard deviation of less than 6% in flow velocities when estimated for a range of SNR levels. The RMG method is validated in a custom-designed experimental setup, Doppler phantom and imitation blood flow control system. In vitro experimental results show that the mean error of the RMG algorithm is 4.81%. Low errors in blood volume flow estimation make the prospect of using the RMG algorithm for real-time blood volume flow estimation possible.

Implantable Flexible Sensor for Telemetrical Real-Time Blood Pressure Monitoring using Polymer/Metal Multilayer Processing Technique (폴리머/ 금속 다층 공정 기술을 이용한 실시간 혈압 모니터링을 위한 유연한 생체 삽입형 센서)

  • Lim Chang-Hyun;Kim Yong-Jun;Yoon Young-Ro;Yoon Hyoung-Ro;Shin Tae-Min
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.599-604
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    • 2004
  • Implantable flexible sensor using polymer/metal multilayer processing technique for telemetrical real-time blood pressure monitoring is presented. The realized sensor is mechanically flexible, which can be less invasively implanted and attached on the outside of blood vessel to monitor the variation of blood pressure. Therefore, unlike conventional detecting methods which install sensor on the inside of vessel, the suggested monitoring method can monitor the relative blood pressure without injuring blood vessel. The major factor of sudden death of adults is a disease of artery like angina pectoris and myocardial infarction. A disease of circulatory system resulted from vessel occlusion by plaque can be preventable and treatable early through continuous blood pressure monitoring. The procedure of suggested new method for monitoring variation of blood pressure is as follows. First, integrated sensor is attached to the outer wall of blood vessel. Second, it detects mechanical contraction and expansion of blood vessel. And then, reader antenna recognizes it using telemetrical method as the relative variation of blood pressure. There are not any active devices in the sensor system; therefore, the transmission of energy and signal depends on the principle of mutual inductance between internal antenna of LC resonator and external antenna of reader. To confirm the feasibility of the sensing mechanism, in vitro experiment using silicone rubber tubing and blood is practiced. First of all, pressure is applied to the silicone tubing which is filled by blood. Then the shift of resonant frequency with the change of applied pressure is measured. The frequency of 2.4 MHz is varied while the applied pressure is changed from 0 to 213.3 kPa. Therefore, the sensitivity of implantable blood pressure is 11.25 kHz/kPa.

The Study of Compatibility for Method of Analysis of Nonlinear Characteristics of Blood Flow of Peripheral in Rabbit (토끼에 있어서 말초혈류운동의 비선형특성분석방법의 적합성에 관한 연구)

  • 남상희;최준영;이상훈
    • Progress in Medical Physics
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    • v.8 no.1
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    • pp.75-82
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    • 1997
  • The human physiological systems are so complex and irregular dynamics. Dynamics of peripheral blood vessel, in particular, have quite sensitive and complex. Before, the linear analytic method have been used to analyze the system. But, the method have many problems to predict the following results. In the other hand, the nonlinear analytic method, chaotic time series analysis method, is suitable for measuring complex, vary system. In this study, the scalar data of the blood flow of peripheral blood vessel of rabbits, in accordance with injection of glucose, was obtained and redefined as multi-dimensional vectors, with time-series analytic methods. This study also intended to confirm that the peripheral blood flow is chaotic dynamics and evaluate the availability of non-linear analytic method. As a result, the existing FFT, and mean could show the difference of blood flow of peripheral blood vessel by injection of glucose, but the nonlinear analytic method could show the definite difference. The hemodynamics is a chaotic phenomenon.

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An Experimental Study on the Effects of Aebaegeum Applicable to the Treatment of Epistaxis (鼻出血에 應用되는 艾柏飮의 效能에 關한 實驗的 硏究)

  • Hong, Ik-Pyo;Chae, Byeong-Yun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.3 no.1
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    • pp.1-15
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    • 1990
  • Aebaegeum has been widely used in the treatment of epistaxis, as based on Oriental Medical 1iteratures. In order to investigate experimentally the clinical effects of Aebaegeum, hemostatic time, plasma recalcification time and prothrombin time of hypoprothrombinemia induced by warfarin injection, action on isolated ileum, action on blood vessel, action on blood pressure and respiration and action on heart were observed. The result of the studies were obtained as follows: 1. Hemostatic time of vein ruptured mice was significantly shortened. 2. Plasma recalification time and prothrombin time of hypoprothrombinemic rats induced by warfarin injection were significantly shortened. 3. Spontaneous mobilities in the isolated ileum of mice were significantly suppressed, and contraction by acetylcholine chloride and barium chloride were inhibited. 4. Dilatation of blood vessel and downing of blood pressure of rabbit were noted. 5. Contraction of heart in the original position and isolated heart of frog were significantly shortened. According to the above result, it is expected that Aebaegeum can be widely applicable to the treatment of epistaxis.

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Velocity and Shear Stress Distributions for Steady and Physiological Flows in the Abdominal Aorta/lLIAC Artery Bifurcation (복부대동맥/장골동맥 분기혈관내 정상 및 박동성 유동의 속도와 전단응력분포)

  • 서상호
    • Journal of Biomedical Engineering Research
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    • v.18 no.2
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    • pp.179-186
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    • 1997
  • Steady and physiological flows of a Newtonian fluid and blood in the abdominal gorta/iliac artery bifurcation are numerically simulated to understand the etiology and pathogenesis of atherosclerosis. Distributions of velocity, pressure, and wall shear stress in the bifurcated arterial vessel model are calculated to investigate the differences of flow characteristics between steady and physiological flows and to compare flow characteristics of blood with that of a Newtonian fluid For the given Reynolds number the flow characteristics of physiological flows for a Newtonian fluid and blood in the bifurcated arterial vessel are quite different from thcse of steady flows. No flow separation or flow reversal in the bifurcated region appears downstream of a stenosis during the acceleration phase. However, during the deceleration phase the flow exhibits flow separation in the outer walls of daugtlter branches, which extends to the entire wall region.

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Coronary Vessel Segmentation by Coarse-to-Fine Strategy using Otsu Algorithm and Decimation-Free Directional Filter Bank

  • Trinh, Tan Dat;Tran, Thieu Bao;Thuy, Le Nhi Lam;Shimizu, Ikuko;Kim, Jin Young;Bao, Pham The
    • Journal of IKEEE
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    • v.23 no.2
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    • pp.557-570
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    • 2019
  • In this study, a novel hierarchical approach is investigated to extract coronary vessel from X-ray angiogram. First, we propose to combine Decimation-free Directional Filter Bank (DDFB) and Homographic Filtering (HF) in order to enhance X-ray coronary angiographic image for segmentation purposes. Because the blood vessel ensures that blood flows in only one direction on vessel branch, the DDFB filter is suitable to be used to enhance the vessels at different orientations and radius. In the combination with HF filter, our method can simultaneously normalize the brightness across the image and increases contrast. Next, a coarse-to-fine strategy for iterative segmentation based on Otsu algorithm is applied to extract the main coronary vessels in different sizes. Furthermore, we also propose a new approach to segment very small vessels. Specifically, based on information of the main extracted vessels, we introduce a new method to extract junctions on the vascular tree and level of nodes on the tree. Then, the window based segmentation is applied to locate and extract the small vessels. Experimental results on our coronary X-ray angiography dataset demonstrate that the proposed approach can outperform standard method and attain the accuracy of 71.34%.

Mechanical Dilation of the Recipient Vessel with the DeBakey Vascular Dilator in Lower Extremity Reconstruction: A Report of Two Cases

  • Min-Gi Seo;Tae-Gon Kim
    • Archives of Plastic Surgery
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    • v.50 no.3
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    • pp.311-314
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    • 2023
  • In lower extremity reconstruction, the recipient vessel often requires long-range mechanical dilation because of extensive vasospasm or plaque formation induced by concomitant atherosclerosis. While a forceps dilator can be used to manipulate and dilate vessels approximately 1 cm from their end, a DeBakey vascular dilator can dilate long-range vessels. The authors successfully performed free flap reconstruction of the lower extremity using the DeBakey vascular dilator. Of the two patients who underwent lower extremity reconstruction, one had extensive vasospasm, and the other had plaques in the recipient arteries. Irrigation with 4% lidocaine and dilation of the lumen with a forceps dilator were insufficient to restore the normal arterial blood flow. Instead, a DeBakey vascular dilator with a 1-mm diameter tip was gently inserted into the lumen. Then, to overcome vessel resistance, the dilator gently advanced approximately 10 cm to dilate the recipient artery. Normal arterial blood flow was gushed out after dilating the vessel lumen using a DeBakey vascular dilator. The vascular anastomosis was performed, and intravenous heparin 5000 IU was administered immediately after anastomosis. Prophylactic low-molecular-weight-heparin (Clexane, 1 mg/kg) was administered subcutaneously to both patients for 14 days. The reconstructed flap survived without necrosis in either patient.

A Study on the Collateral Vessel Pathology(絡脈病機) of Blood Disease(血證) in Onbyeong(溫病) with focus on Ju-Gaek-Gyo(主客交, guest-host minglement) and Dry Blood(乾血) (온병(溫病) 혈증(血證)의 낙맥병기(絡脈病機)에 대한 고찰 -주객교(主客交)와 건혈(乾血)을 중심으로-)

  • Kim, Dong-Hui;Jeong, Chang-Hyun;Jang, Woo-Chang;Lyu, Jeong-Ah;Baik, You-Sang
    • Journal of Korean Medical classics
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    • v.25 no.1
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    • pp.89-115
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    • 2012
  • Objective : Blood disease is common these days due to modern man's excessiveness in Yang heat (陽熱) and vulnerability of the Eum blood(陰血). This exposes them to warmheat/ dampness-heat diseases, where pathogenic heat easily penetrates the blood dimension(血分) creating stagnated blood(瘀血). Consequently, pathogenic symptoms in the collateral vessels increase, making it crucial to understand the pathogenic mechanism of the disease. Method : This paper examines the condition and region of the collateral vessel diseases(CVD) according to the blood diseases of Onbyeong, by analyzing each prescription's matching symptom. The disease in question in this paper is 'stagnated blood fixated in the collateral vessels'. Therefore diseases with stagnated blood in the Yang collaterals and Viscera collaterals or viscera themselves from the chapter of "On-Yeok-Ron(溫疫論)", and < Dry Blood-DaeWhangJaChungWhan(大黃蟅蟲丸) > chapter of "Geum-Gue-Yo-Rak(金匱要略)", were examined respectively. Result & Conclusion : The process of CVD according to the blood diseases of Onbyeong can be summarized as follows. First, bleeding in the Yang and Bowel collaterals, then stagnation in the Yang and Bowel collaterals, and finally stagnation in the viscera collaterals or Liver itself. The refractory nature of blood stagnation symptoms of the collateral vessels is mainly due to the characteristics of the collateral vessel itself. In structure, they are very narrow and small, situated at the most terminal part of the body where it is difficult for the Jeong Gi(精氣) to reach. Also, as they are symptomatic of degeneration of Jeong Gi, the root of the disease is very deep. Therefore to resolve blood stagnation in the cases of Ju-Gaek-Gyo and Dry Blood, general approaches using 'Gi communication(行氣)' or 'Blood vitalizing(活血)' medicinals will not suffice. Special medicinals such as crustacean and insects need to be appropriately applied.

Generation Method of Spatiotemporal Image for Detecting Leukocyte Motions in a Microvessel (미소혈관내 백혈구 운동검출을 위한 시공간 영상 생성법)

  • Kim, Eung Kyeu
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.9
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    • pp.99-109
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    • 2016
  • This paper presents a method for generating spatiotemporal images to detect the leukocyte motions in a microvessel. By using the constraint that the leukocytes move along the contour line of a blood vessel wall, the method detects leukocyte motions and then generates spatiotemporal images. the translational motion by a movement in vivo is removed first by the template matching method. Next, a blood vessel region is detected by the automatic threshold selection method to binarize the temporal variance image, then a blood vessel wall's contour is expressed by B-spline function. With the detected blood vessel wall's contour as an initial curve, the plasma layer of the best accurate position is determined to be the spatial axis by snake. Finally, the spatiotemporal images are generated. The experimental results show the spatiotemporal images are generated effectively through the comparison of each step of three image sequences.

Edge Extraction using Fuzzy Techniques in Coronary Artery Image (Fuzzy 기법을 이용한 관상동맥영상의 에지추출)

  • Kim, Seong-Hu;Lee, Ju-Won;Kim, Joo-Ho;Lee, Han-Wook;Jung, Won-Geun;Lee, Gun-Ki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.3
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    • pp.585-590
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    • 2012
  • Coronary Intervention treatment has become the core that is the test of cardiac catheterization to conduct treatment with Coronary Arteriography. Operators must be careful in Coronary Intervention treatment because the stent is inserted into the point of narrowing of blood vessel. So, the operator must correctly recognize the path of blood vessel to deal with the problems which are damages and ruptures of blood vessel, and there would be some errors of finding the path of blood vessel by bad qualify of the image. Therefore in this paper, median filtering is conducted by preprocessing to evaluate the performance of the effect of noise of the image that affects quality of the image and Fuzzy Edge Extraction Techniques is tested by using Soble Edge Extraction Techniques to compare the performance with The Fuzzy Edge Extraction Techniques. In result, the performance, removing the noise and extracting the signal of Fuzzy Edge Extraction Techniques using median filtering, demonstrates the superiority.