Analysis of contour sharpness.

<p>The DICOM images were interpolated by Vitrea fx. The measurement is based on a straight line that is placed orthogonal to the vessels course connecting the epicardial tissue on both sides of the vessel at the example of RCA (<b>a-d</b>); <b>e-h</b>: gray values in HU along the line above the vessel for the analysis of contour sharpness; see <b><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0125943#pone.0125943.s007" target="_blank">S5 Table</a></b> for statistical results; <b>a/e:</b> combined filtered back projection and quantum denoising filtering software; <b>b/f:</b> adaptive iterative dose reduction three-dimensional (AIDR 3D) mild; <b>c/g:</b> AIDR 3D standard; <b>d/h:</b> AIDR 3D strong; <b>i:</b> The analysis of contour sharpness is based on the difference between 25% and 75% of the maximal gray value (max.) and the maximal slope of gray values between two pixels in percent of the difference between minimal (min.) and maximal density.