The study described main features of coronary in stent restenosis on IVUS including morphological characteristics (focal or diffuse proliferative stenosis), stenosis site (stent body or stent margin), undeployment stent characteristics (underexpansion, malapposition, fracture stent, crush stent, stent gap, overlap stent), other characteristics of the lumen (such as the size of the lumen, endothelial proliferation...), the characteristics of remodeling vascular after stenting.