 Intravascular ultrasound IVUS has been largely used as an adjunctive diagnostic tool during percutaneous coronary intervention PCI. When fully explored, IVUS provides precise information for guiding the PCI strategy. IVUS allows accurate vessel and lesion sizing, determination of plaque calcification and the need for pre-stent plaque preparation, assessment of post-stent results including edge dissections and residual lesion, as well as stent underexpansion or incomplete apposition. Therefore, IVUS has the potential to reduce the utilization of contrast media during PCI. 