Depth-resolved imaging of myocardial excitation

心肌兴奋的深度分辨成像

• 批准号: 6772628
• 负责人: Arkady M PERTSOV
• 金额: $ 22.8万
• 依托单位: UPSTATE MEDICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6772628
• 关键词: Internet; bioimaging /biomedical imaging; computer program /software; computer simulation; computer system design /evaluation; dyes; heart electrical activity; image processing; light scattering; membrane potentials; model design /development; myocardium; three dimensional imaging /topography

DESCRIPTION (provided by applicant): Understanding the mechanisms that underlie abnormalities of electrical conduction in the heart is the key to the development of effective antiarrhythmic therapies. During the last decade, significant progress has been made in imaging electrical excitation waves in the heart using voltage-sensitive fluorescent dyes. However, until recently imaging that uses voltage-sensitive dyes was limited primarily to the epicardial surface. Therefore the design of tools for visualization of electrical activity inside the myocardial wall is likely to have a major impact on the field. The ultimate goal of the proposed studies is to develop a new optical imaging technology for detecting sources of arrhythmia hidden inside the myocardial wall. The new technology will combine methods of diffusive optical tomography with specific knowledge of electrical processes in the heart and their characteristics. The first major step towards our main objective will be to create a family of realistic tissue-specific and dye-specific computer models for reconstructing optical images from 3D distributions of the transmembrane potential in myocardial tissue (forward problem). Using this methodology, termed below virtual optical imaging (VOI), we will create a web-accessible library containing the optical signatures of major types of activation patterns. The solution of the forward problem will provide key elements for solving the inverse problem - reconstructing 3D distributions of the transmembrane potential from optical signals. The specific aims of the project are: 1) To develop a realistic model of light transport in myocardial tissue based on direct measurements of light absorption and scattering. 2) To couple the light transport model to a model of electrical wave propagation. The combination will predict voltage-dependent optical signals during normal propagation and 3-dimensional reentrant activity. 3) To develop and validate experimental techniques and deconvolution algorithms for imaging intramural sources of excitation including ectopic foci producing radial spread of excitation, and scroll wave filaments - the organizing centers of 3D reentrant activity in myocardial tissue. Successful completion of the project should significantly improve ones ability to interpret optical recordings and will ultimately enable depth-resolving detectors for imaging the intramural sources underlying the most lethal arrhythmias.

描述（由申请人提供）：了解心脏电传导异常的机制是开发有效抗心律失常治疗的关键。在过去的十年中，在使用电压敏感荧光染料成像心脏中的电激发波方面取得了重大进展。然而，直到最近，使用电压敏感染料的成像主要限于心外膜表面。因此，用于心肌壁内电活动可视化的工具的设计可能对该领域产生重大影响。本研究的最终目标是开发一种新的光学成像技术，用于检测隐藏在心肌壁内的心律失常源。这项新技术将联合收割机的扩散光学断层扫描方法与心脏电过程及其特征的具体知识相结合。实现我们的主要目标的第一个主要步骤将是创建一个家庭的现实的组织特异性和染料特异性的计算机模型，用于从心肌组织中的跨膜电位的3D分布重建光学图像（前向问题）。使用这种方法，下面称为虚拟光学成像（VOI），我们将创建一个网络访问的图书馆，包含主要类型的激活模式的光学签名。正问题的解决将为解决反问题提供关键要素-从光信号重建跨膜电位的3D分布。本课题的具体目标是：1）建立一个基于直接测量光吸收和散射的光在心肌组织中传输的真实模型。2)将光传输模型耦合到电波传播模型。该组合将预测正常传播和三维再入活动期间的电压依赖性光信号。3)开发并验证用于成像壁内兴奋源的实验技术和去卷积算法，包括产生径向兴奋扩散的异位病灶和涡卷波丝-心肌组织中3D折返活动的组织中心。该项目的成功完成将大大提高人们解释光学记录的能力，并最终使深度分辨探测器能够对最致命的心律失常的壁内源进行成像。