Comparing Two Examination Methods for Measuring Metal to Artery Ratio of Coronary Stents

This article shows two examination methods to measure the metal to artery ratio of stents. Our goal was to further develop the previously used measuring method in order to make it suitable for the integration into the quality control process of endovascular stent manufacture to provide more realistic data. The previous method was performed manually using rotating equipment under a stereomicroscope. The new method is an automatic method using an integrated scanner and a rotating engine. Both methods aimed at converting the cylindrical stent into a flattened two-dimensional image in order to enable the measurement of stent surface area by imaging software. From the image we can determine the cell sizes, the maximum achievable stent diameter, and the structure of the stent pattern. Each measurement process was tested on different types of stents. Our findings showed that the methods gave similar results, the largest differences are speed and accuracy.