Optical coherence tomography (OCT) is an established intravascular imaging technique that uses light sources to capture inside of the coronary artery using very high resolution, 3D images from within the coronary artery lumen. Optical coherence tomography is based on typically employing near-infrared light. The use of relatively long wavelength light allows it to penetrate the contrast medium. This imaging technique is highly superior in assessing the minute details about the type of blockages, also about the stent properly apposed or not in the area of blockages.
Intravascular ultrasound (IVUS) is another intravascular imaging technique using a specially designed catheter with a mini ultrasound probe attached to the distal end of the catheter. The proximal end of the catheter is attached to computerized ultrasound equipment. It allows the application of ultrasound technology, such as a piezoelectric transducer or CMUT, to see from inside blood vessels out through the surrounding blood column, visualizing the endothelium (inner wall) of blood vessels in living individuals and good for sizing the vessel especially left main coronary artery for deploying accurate size stents or scaffords.