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.
