GEOMETRIC MAPPING OF TISSUE HEART VALVES

生物组织心脏瓣膜的长期(10年以上)耐用性部分取决于设计最佳的瓣叶几何形状，从而将拉伸和弯曲应力集中和磨损降至最低。最理想的是，阀门的设计和制造应该在不同单元之间的生理压力和流动条件下使用相同的叶片应力和应变率。目前这是不可能的，主要是因为缺乏准确的定量几何测绘系统。Vision Metrics建议调整其DMEyes地形图绘制系统，以绘制组织心脏瓣膜图。Vision Metrics，Inc.的S DMEyes使用了一种机器视觉系统，旨在保持对各种材料的映射精度。地形图直接从三维笛卡尔坐标(X、Y和Z数据点)数据数组中获得。测量是基于主射线三角剖分的原理。校准的光图案被投射到心脏瓣膜上，并由摄像机成像。校准点的位置被用来根据投影的主射线和成像的主射线的交点来确定表面的形状。没有对曲面的形状做出任何假设。拟议的商业应用：Vision Metrics DMEyes组织拓扑仪针对心脏瓣膜测绘进行了优化，预计将由参与组织和生物材料心脏瓣膜开发和设计的研究人员和生物工程师以及制造和质量保证工程师用于对制造的组织心脏瓣膜进行过程测试。使用密切相关的DMEyes技术的其他组织测绘应用程序预计将效仿心脏瓣膜测绘应用程序。

The long term (10 year plus) durability of biological tissue heart valves depends in part on designing optimal leaflet geometry which minimizes tensile and flexion stress concentrations and abrasion. Optimally, the valve should be designed and manufactured with identical leaflet stress and strain rates under physiological pressure and flow conditions from unit to unit. This is currently not possible, due, primarily, to the lack of an accurate quantitative geometric mapping system. Vision Metrics proposes to adapt its DMEyes topographic mapping system to mapping tissue heart valves. Vision Metrics, Inc.'s DMEyes uses a machine vision system designed to maintain mapping accuracy for a wide range of materials. Topographic maps are directly obtained from a three dimensional Cartesian coordinate (X, Y, and Z data points) data array. Measurements are based on the principle of chief ray triangulation. A calibrated light pattern is projected onto the heart valve and imaged by a video camera. The locations of the calibrated points are used to determine the shape of the surface from the intersections of the projected chief rays and the imaged chief rays. No assumptions are made about the shape of the surface. PROPOSED COMMERCIAL APPLICATION: A Vision Metrics DMEyes tissue topographer optimized for heart valve mapping is expected to be used by researchers and bioengineers involved with the development and design of tissue and biomaterial heart valves and by manufacturing and quality assurance engineers for in process testing of manufactured tissue heart valves. Other tissue mapping applications, using closely related DMEyes technology, are expected to follow from the heart valve mapping application.