FIBEROPTIC CONFOCAL IMAGING FOR ID OF CONDUCTION TISSUE DURING CARDIAC SURGERY

描述（由申请人提供）：申请人的长期目标是建立光纤共聚焦显微镜作为心脏手术的术中成像方式，特别是在儿科心内直视手术中。心脏手术的一个主要风险是传导系统的损伤，而传导系统能够使心房和心室同步激活。传导系统的损害是不可逆的，需要昂贵的起搏器插入，并与显著的发病率相关。尽管传导系统存在个体差异，但手术过程中的组织识别目前仅限于解剖标志的视觉识别。我们的初步数据表明，心脏组织的显微图像为各种类型的心脏组织的视觉辨别提供了足够的信息。在这个项目中，我们将使用光纤共聚焦显微镜和专门的成像微探针在动物模型中测试心房和结组织可以区分的假设。在第一个具体目标中，我们将应用我们之前工作中建立的技术来创建和分析固定兔心脏的心房，窦房结（SAN）和房室结（AVN）组织的三维（3D）重建。我们将使用荧光标记，传统的扫描共聚焦显微镜和数字图像处理方法来创建这些高分辨率的组织微观结构3D模型。在第二个具体目标中，我们将开发和评估用于心脏组织表征的光纤微探针。这项工作将与北美的莫纳克亚科技公司合作进行，这为我们的研究团队提供了独特的专业知识，以开发专门用于心脏组织鉴别的微探针。微探针的设计和评估将基于从第一个特定目标中开发的3D重建中提取的组织参数。将设计、开发和评估几种微型探针的原型。在第三个特定目标中，我们将利用光纤共聚焦显微镜和专门的微探针（在第二个特定目标中开发）来表征心房、SAN和AVN组织。我们将使用光纤共聚焦显微镜获取二维图像数据，并使用图像处理方法和目视检查对其进行表征。所有特定的目的都是为了验证我们的假设，即光纤共聚焦显微镜的图像足以区分心房、SAN和AVN组织。

DESCRIPTION (provided by applicant): The applicants' long-term aim is to establish fiber-optics confocal microscopy as an intraoperative imaging modality in cardiac surgery, in particular in pediatric open heart surgery. A major risk of cardiac surgery is damage of the conduction system, which enables synchronized activation of atria and ventricles. Damage of the conduction system is irreversible, necessitates costly pacemaker insertion and is associated with significant morbidity. Despite individual variations in the conduction system, tissue discrimination during surgery is currently limited to the visual identification of anatomical landmarks. Our preliminary data indicate that microscopic images of cardiac tissue provide sufficient information for visual discrimination of various types of cardiac tissue. In this project, we will test the hypothesis that atrial and nodal tissue can be discriminated in an animal model using fiber-optics confocal microscopy and specialized imaging micro-probes. In the first specific aim, we will apply techniques established in our previous work to create and analyze three- dimensional (3D) reconstructions of atrial, sinoatrial node (SAN) and atrio-ventricular node (AVN) tissue from fixed rabbit hearts. We will use fluorescent labeling, conventional scanning confocal microscopy and methods of digital image processing to create these high-resolution micro-structural 3D models of tissue. In the second specific aim, we will develop and evaluate fiber-optics microprobes for characterization of cardiac tissue. This work will be carried out in collaboration with Mauna Kea Technologies, North America, which provides our research team with unique expertise to develop microprobes specialized for discrimination of cardiac tissue. The design and evaluation of microprobes will be based on tissue parameters extracted from the 3D reconstructions developed in the first specific aim. Several prototypes of microprobes will be designed, developed and evaluated. In the third specific aim, we will characterize atrial, SAN and AVN tissues applying fiber-optics confocal microscopy and the specialized microprobes (developed in the second specific aim) to living preparations of rabbit heart. Sets of two-dimensional image data will be acquired with our fiber-optics confocal microscope and characterized using image processing methods and visual inspection. All specific aims are designed towards testing our hypothesis that images from the fiber-optics confocal microscopy are sufficient for discrimination of atrial, SAN and AVN tissue. PUBLIC HEALTH RELEVANCE: Damage of the cardiac conduction system is a major risk of reconstructive heart surgery especially in the treatment of congenital heart defects. Intraoperative imaging has the potential to reduce this risk. This project develops and evaluates approaches for intraoperative imaging based on novel fiber-optics confocal microscopy.