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Automated Segmentation of left ventricle Using Local and Global Intensity Based Active Contour and Dynamic Programming

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International Journal of Automation and computing 2018年第6期15卷 673-688页

作者： G.Dharanibai Anupama Chandrasekharan Zachariah C.Alex School of Electronics Engineering Vellore Institute of Technology (VIT) University Department of Radiology Sri Ramachandra University

The aim of this work is to develop an improved region based active contour and dynamic programming based method for accurate segmentation of left ventricle （LV） from multi-slice cine short axis cardiac magnetic resonance （MR） images. Intensity inhomogeneity and weak object boundaries present in MR images hinder the segmentation accuracy. The proposed active contour model driven by a local Gaussian distribution fitting （LGDF） energy and an auxiliary global intensity fitting energy improves the accuracy of endocardial boundary detection. The weightage of the global energy fitting term is dynamically adjusted using a spatially varying weight function. Dynamic programming scheme proposed for the segmentation of epicardium considers the myocardium probability map and a distance weighted edge map in the cost matrix. Radial distance weighted technique and conical geometry are employed for segmenting the basal slices with left ventricle outflow tract （LVOT） and most apical slices. The proposed method is validated on a public dataset comprising 45 subjects from medical image computing and computer assisted interventions （MICCAI） 2009 segmentation challenge. The average percentage of good endocardial and epicardial contours detected is about 99%, average perpendicular distance of the detected good contours from the manual reference contours is 1.95 mm, and the dice similarity coefficient between the detected contours and the reference contours is 0.91. Correlation coefficient and the coefficient of determination between the ejection fraction measurements from manual segmentation and the automated method are respectively 0.9781 and 0.9567, for LV mass these values are 0.9249 and 0.8554. Statistical analysis of the results reveals a good agreement between the clinical parameters determined manually and those estimated using the automated method.

关键词： Cardiovascular magnetic resonance left ventricle endocardium epicardium myocardium segmentation active contour dynamic programming.

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An Interpretable CNN for the Segmentation of the left ventricle in Cardiac MRI by Real-Time Visualization

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1571-1587页

作者： Jun Liu Geng Yuan Changdi Yang Houbing Song Liang Luo Robotics Institute School of Computer ScienceCarnegie Mellon UniversityPittsburghPA15217USA Department of Electrical&Computer Engineering College of EngineeringNortheastern UniversityBostonMA02115USA Security and Optimization for Networked Globe Laboratory(SONG Lab) Embry-Riddle Aeronautical UniversityDaytona BeachFL32114USA School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China

The interpretability of deep learning models has emerged as a compelling area in artificial intelligence *** safety criteria for medical imaging are highly stringent,and models are required for an ***,existing convolutional neural network solutions for left ventricular segmentation are viewed in terms of inputs and ***,the interpretability of CNNs has come into the *** medical imaging data are limited,many methods to fine-tune medical imaging models that are popular in transfer models have been built using massive public Image Net datasets by the transfer learning ***,this generates many unreliable parameters and makes it difficult to generate plausible explanations from these *** this study,we trained from scratch rather than relying on transfer learning,creating a novel interpretable approach for autonomously segmenting the left ventricle with a cardiac *** enhanced GPU training system implemented interpretable global average pooling for graphics using deep *** deep learning tasks were *** included data management,neural network architecture,and *** system monitored and analyzed the gradient changes of different layers with dynamic visualizations in real-time and selected the optimal deployment *** results demonstrated that the proposed method was feasible and efficient:the Dice coefficient reached 94.48%,and the accuracy reached 99.7%.It was found that no current transfer learning models could perform comparably to the ImageNet transfer learning *** model is lightweight and more convenient to deploy on mobile devices than transfer learning models.

关键词： Interpretable graphics training visualization image segmentation left ventricle CNNs global average pooling

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NONLINEAR DYNAMICS MODFLING OF MECHANICAL PERIODICITY OF END DIASTOLIC VOLUME OF left ventricle

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Applied Mathematics and Mechanics(English Edition) 2001年第10期22卷 1183-1191页

作者： XU Shi-xiong(许世雄) MAO Xiao-chun(毛晓春) Mechanics and Engineering Science Department Fudan UniversityShanghai 200433 P R China Mechanics and Engineering Science Department Fudan UniversityShanghai 200433 P R China

The cardiovascular system with a lumped parameter model is treated, in which the Starling model is used to simulate left ventricle and the four-element Burattini & Gnudi model is used in the description of arterial system. Moreover, the feedback action of arterial pressure on cardiac cycle is taken into account. The phenomenon of mechanical periodicity (MP) of end diastolic volume (EDV) of left ventricle is successfully simulated by solving a series of one-dimensional discrete nonlinear dynamical equations. The effects of cardiovascular parameters on MP is also discussed.

关键词： left ventricle end diastolic volume mechanical periodicity nonlinear dynamics

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Joint segmentation and motion estimation of left ventricle with an anisotropic biomechanical model

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Progress in Natural Science:Materials International 2007年第2期17卷 226-229页

作者： ZHUANG Ling, LIU Huafeng, BAO Hujun ( State Key Laboratory of CAD & CG, Zhejiang University, Hangzhou 310027, China State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou 310058, China) State Key Laboratory of CAD and CG Zhejiang University Hangzhou 310027 China State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310058 China

Accurate estimation of shape and motion variability of the heart has important clinical implications for heart disease diagnosis. In this paper, we describe a framework which performs simultaneous segmentation and motion analysis of the left ventricle from 3D cardiac images. The left ventricle is formulated as an anisotropic linear elastic body represented by a set of tetrahedrons constructed from sampling nodes. The elastic body is evolved by both internal force and external force, and the external force imposed on each node is an integration of edginess measure, shape coherence measure, prior distributions of the myocardial tissues and temporal driven measure. The displacement field and the segmentation result are simultaneously solved at the equilibrium state between the internal energy and the external energy. The experiment with 3D canine MR images illustrated its abilities and benefits.

关键词： left ventricle motion simultaneous estimation deformable model image segmentation.

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left to Right Extracardial Shunt to Control Hemorrhage of Ascending Aorta and left ventricle: A Report of 3 Cases

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Journal of Huazhong University of Science and Technology(Medical Sciences) 1998年第3期18卷 177-179页

作者：刘成硅杨辰垣张凯伦孙宗权肖诗亮蓝鸿钧 Department of Cardiac Surgery Institute of Cardiovascular Diseases Tongji Medical University Wuhan

Presented in this paper are 3 cases of hemorrhage of ascending aorta and left ventricle after open heart surgery treated by extracardial bypass in our hospital from Oct. 1994 to Dec. 1995. Remained aneurysmal wall enclosing conduit graft was used as a sac bypassed to right atrium to form a extracardial left-toright shunt in order to control bleeding and the results turned out to be satisfactory. The bypass and hemodynamically ignorable shunt can close spontaneously without complications with recovery of coagulation system. The technique may find wide application in clinical practice.

关键词： left-to-right extracardial shunt hemorrhage ascending aorta left ventricle

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Value of clinical applications of differential pressure and relative pressure imaging in the left ventricle

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World Journal of Clinical Cases 2023年第17期11卷 3967-3975页

作者： An-Sheng Zheng Hong-Xia Yu Department of Ultrasound Medicine The Second Affiliated Hospital of Zhengzhou UniversityZhengzhou 450002Henan ProvinceChina

Regional pressure differences between sites within the left ventricular cavity have long been identified,and the potential clinical value of diastolic and systolic intraventricular pressure differences(IVPDs)is of increasing *** study concluded that the IVPD plays an important role in ventricular filling and emptying and is a reliable indicator of ventricular relaxation,elastic recoil,diastolic pumping,and effective left ventricular *** pressure imaging,as a novel and potentially clinically applicable measure of left IVPDs,enables early and more comprehensive identification of the temporal and spatial characteristics of *** the future,as research related to relative pressure imaging continues,this measurement method has the possibility to become more refined and serve as an additional clinical aid that can replace the gold standard cardiac catheterization technique for the diagnosis of diastolic dysfunction.

关键词： Cardiac imaging techniques Echocardiography Ventricular dysfunction left ventricle Cardiovascular physiological phenomena Hemodynamics Ventricular pressure

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Fluid-structure interaction simulation of pathological mitral valve dynamics in a coupled mitral valve-left ventricle model

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智慧医学(英文) 2023年第2期3卷 104-114页

作者： Li Cai Tong Zhao Yongheng Wang Xiaoyu Luo Hao Gao NPU-UoG International Cooperative Lab for Computation and Application in Cardiology School of Mathematics and StatisticsNorthwestern Polytechnical UniversityXi’anShaanxi 710129China Xi’an Key Laboratory of Scientific Computation and Applied Statistics Xi’anShaanxi 710129China School of Mathematics and Statistics University of GlasgowGlasgowG128QQUnited Kingdom

Background Understanding the interaction between the mitral valve(MV)and the left ventricle(LV)is very important in assessing cardiac pump function,especially when the MV is *** dysfunction is a major medical problem owing to the essential role of the MV in cardiac pump *** modelling can provide new approaches to gain insight into the functions of the MV and *** In this study,a previously developed LV-MV model was used to study cardiac dynamics of MV leaflets under normal and pathological conditions,including hypertrophic cardiomyopathy(HOCM)and calcification of the *** coupled LV-MV model was implemented using a hybrid immersed boundary/finite element method to enable assessment of MV haemodynamic *** parameters of the HOCM and calcified valves were inversely determined from published experimental *** LV compensation mechanism was further studied in the case of the calcified *** Our results showed that MV dynamics and LV pump function could be greatly affected by MV *** example,the HOCM case showed bulged MV leaflets at the systole owing to low stiffness,and the calcified MV was associated with impaired diastolic filling and much-reduced stroke *** further demonstrated that either increasing the LV filling pressure or increasing myocardial contractility could enable a calcified valve to achieve near-normal pump *** The modelling approach developed in this study may deepen our understanding of the interactions between the MV and the LV and help in risk stratification of heart valve disease and in silico treatment planning by exploring intrinsic compensation mechanisms.

关键词： Mitral valve left ventricle Valve disease Hybrid immersed boundary/finite element method Calcification Hypertrophic cardiomyopathy

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Diagnostic Accuracy of Strain Imaging of the left ventricle in Detection of Obstructive Coronary Artery Disease

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World Journal of Cardiovascular Diseases 2020年第8期10卷 572-586页

作者： Mohamed Fahmy Elnoamany Waleed Abdou Ibrahim Ahmed Mahmoud Hamza Menoufia University Menoufia Egypt Mahalla Cardiac Center Gharbia Egypt

Background: Speckle tracking echocardiography using average global strain and strain rate (SR) parameters for early detection of high risk patients with coronary artery disease (CAD) has gained a substantial clinical interest. Objective: Assessment of the diagnostic accuracy of strain imaging of the left ventricle in detection of obstructive coronary artery disease. Methods: One hundred patients were enrolled. They were divided into 3 groups: Group I (n = 40 patients) presented with ST segment elevation myocardial infarction (STEMI), Group II (n = 40 patients) presented with non-ST segment elevation myocardial infarction (NSTEMI) or unstable angina (UA) and Group III (n = 20 patients) with normal coronary angiography served as a control group. All patients were subjected to 2D speckle tracking echocardiography (2D STE) to assess LV longitudinal strain and strain rate (SR). Sensitivity, specificity and diagnostic accuracy of 2D STE in prediction of CAD and its severity using Gensini score were assessed. Results: The mean age for Group I, II and III was 52.20 ± 11.83, 51.97 ± 14.53 and 52.75 ± 10.75 respectively. LV average global systolic strain (AGS) was significantly lower in group I and II when compared to group III. AGS and average global systolic SR showed significa

关键词： Coronary Artery Disease left ventricle Strain Imaging

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Effect of rheumatic mitral stenosis on end-diastolic volume of left ventricle

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China Medical Abstracts 2007年第2期16卷 160-162页

作者：王云李军朋万荣华顾继伟赵金超侯小东刘旭东 Department of Cardiothoracic Surgery Ningxia Medical College Hospital Yinchuan Ningxia 750004 China

Objective To investigate the relations between the pathological contraction of the valve and sub-valvular apparatus in rheumatic mitral stenosis and end-diastolic volume of left ventricle. Method From 1990-2004, 90 patients with only moderate or severe rheumatic mitral stenosis （mitral group）, and 24 patients with combined moderate or severe rheumatic mitral stenosis and significant aortic regurgitation （ combined valves group）, diagnostically confirmed by surgery and pathology, were measured using echocardiaogram the end-diastolic volume and diameter, stroke volume and ejection fraction of left ventricle. Result Compared with mitral group combined valves group showed slight increases of end-diastolic volume and diameter （116.49 ± 37.93 ml and 136.72±70.67 ml, respectively; 49.34 ± 6.71 mm and 51.08 ± 8.32 mm, respectively; both P 〈 0.05）, and slight decreases of ejection fraction, but significant increases of stroke volume （71.37 ± 25.01 ml and 91.06 ± 36.67 ml, respectively; P〈0.05） of left ventricle. Conclusion The pathological shortening of mitral valve and sub-valvular apparatus caused by long-term rheumatic disease is the main cause of decreased left ventricular volume in mitral stenosis.

关键词： rheumatic mitral stenosis left ventricle end-diastolic volume

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COUPLING BETWEEN THE left ventricle AND ARTERIAL SYSTEM IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION

COUPLING BETWEEN THE LEFT VENTRICLE AND ARTERIAL SYSTEM IN P...

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第2届世界华人生物医学工程研讨会

作者： Jia-Jung Wang Huang-Jui Hsu Heng-Jung Chang Wei-Chih Hua Chun-Peng Liu And Tsiar Kao Dept. of Biomedical Engineering I-Shou University Kaohsiung Taiwan China 2Dept. of Biomedical Engineering Chung-Yuan Christian University Taiwan China 3Dept. of Internal Medicine Kaohsiung Veterans General Hospital Kaohsiung Taiwan China 4Institute of Biomedical Engineering National Yanh-Ming Uninversity Taiwan China

In the study, 11 patients with acute myocardial infarction (AMI) during catheterization are recruited to assess thecoupling between the arterial system and left ventricle. The coupling degree is prese

关键词： left ventricle Arterial system Arterial effective elastance Elastance Acute myocardial infarction

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