Malapposition (arrows) occurs when the axial distance between the stent strut’s surface to the luminal surface is greater than the strut thickness (including the polymer if present). If this distance is less than the strut thickness, then the strut is considered apposed. Two forms of apposition have been described: protruding, where the endoluminal strut boundary is located above the level of the luminal surface, and embedded, where the endoluminal strut boundary is below the level of the luminal surface.