LV Strain Quantification from 4D Echocardiography

描述(由申请人提供)：准确、全面、量化的局部左心室(LV)变形对于检测、风险分层和治疗缺血性心脏病患者至关重要。在这项BRP中，来自两个学术机构和产业界的四个合作伙伴将共同开发和验证一种集成的成像/图像分析系统，该系统将根据四维(3个空间维度和时间)超声心动图(4DE)图像序列准确、可靠和可重复性地量化局部LV应变和应变率。密歇根大学的马修·奥唐奈领导的一个团队正在开发一种基于相敏相关的斑点跟踪方法，该方法将估计壁内位移。这些信息将从从超声阵列获取的射频(RF)信号数据中获得，利用由飞利浦医疗系统公司的Jeff Power博士领导的团队开发的方法，可以访问波束形成的声学数据。心肌表面的位移信息将使用由耶鲁大学博士詹姆斯·邓肯领导的团队开发的形状跟踪策略从B型图像中获得，詹姆斯·邓肯也将担任BRP的PI。壁内和表面位移信息将使用基于生物力学模型(也是耶鲁大学正在开发的)的综合分段/变形估计器进行组合，以提供对心肌应变、应变率和材料参数的全面、4D估计。该方法将使用幻影和与耶鲁大学心脏病学家阿尔伯特·辛努萨斯医学博士领导的团队合作进行体内测试来验证/评估。体内评估将包括基于急性和慢性犬缺血性损伤模型的实验，以量化损伤的跨壁性、随后的左室重构和对ACE抑制剂治疗的反应。临床可行性将在人体试验中确定。4DE得出的LV形变指数将被证明与磁共振(MR)标记得出的指数相当。

DESCRIPTION (provided by applicant): Accurate, comprehensive, quantification of regional left ventricular (LV) deformation is crucial for detection, risk stratification, and management of patients with ischemic heart disease. In this BRP, four partners from two academic institutions and industry will work together to develop and validate an integrated imaging/ image analysis system that will accurately, robustly and reproducibly quantify regional LV strain and strain rate from four-dimensional (3 spatial dimensions and time) echocardiographic (4DE) image sequences. Intramural displacement will be estimated using a phase-sensitive-correlation-based speckle tracking approach being developed by a team lead by Matthew O'Donnell at the University of Michigan. This information will be derived from radiofrequency (RF) signal data acquired from an ultrasound array, giving access to beam-formed acoustic data, using an approach being developed by a team lead by Jeff Powers, Ph.D. from Philips Medical Systems. Displacement information at the myocardial surface will be derived from B-mode images using a shape-tracking strategy being developed by a team lead by James Duncan, Ph.D. at Yale University, who will also serve as the PI of the BRP. Intramural and surface displacement information will be combined using an integrated segmentation/deformation estimator based on a biomechanical model (also being developed at Yale), to provide comprehensive, 4D estimates of myocardial strains, strain rates and material parameters. The approach will be validated/evaluated using phantoms and in vivo testing in collaboration with a team lead by Yale cardiologist Albert Sinusas, M.D. In vivo evaluation will include experiments based on acute and chronic canine models of ischemic injury for the quantification of transmurality of injury, subsequent LV remodeling and response to ACE inhibitor therapy. Clinical feasibility will be established in human studies. The 4DE-derived indices of LV deformation will be shown to be comparable to those derived from Magnetic Resonance (MR) tagging.