LV Strain Quantification from 4D Echocardiography

描述（由申请人提供）：准确、全面、量化局部左室（LV）变形对缺血性心脏病患者的检测、风险分层和管理至关重要。在这个BRP中，来自两家学术机构和工业界的四个合作伙伴将共同开发和验证一个集成成像/图像分析系统，该系统将准确、稳健和可重复地量化来自四维（3个空间维度和时间）超声心动图（4DE）图像序列的区域左室应变和应变率。内部位移将使用由密歇根大学马修·奥唐纳领导的团队开发的基于相位敏感相关的散斑跟踪方法来估计。这些信息将从从超声波阵列获取的射频（RF）信号数据中获得，使用由飞利浦医疗系统的Jeff Powers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利用由耶鲁大学博士詹姆斯·邓肯（James Duncan）领导的团队开发的形状跟踪策略，从b模式图像中获得，他也将担任BRP的PI。内部和表面位移信息将使用基于生物力学模型（也在耶鲁大学开发）的集成分割/变形估计器进行组合，以提供心肌应变，应变率和材料参数的全面4D估计。该方法将与耶鲁大学心脏病专家Albert Sinusas医学博士领导的团队合作，通过模型和体内测试来验证/评估。体内评估将包括基于急性和慢性缺血性损伤犬模型的实验，以量化损伤的跨壁性、随后的左室重塑和对ACE抑制剂治疗的反应。将在人体研究中建立临床可行性。4de衍生的LV变形指数将被证明与磁共振（MR）标记衍生的指数相当。

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.