OCT (Optical Coherence Tomography)

Optical coherence tomography (OCT) is a well established, semi-invasive medical imaging method that uses light to capture high resolution, three-dimensional subsurface images. It is often equated to ultrasound imaging as the ‘optical ultrasound’ for providing cross-sectional images from within tissue. However, the image resolution provided by OCT is much higher than a traditional ultrasound and even an MRI, making it the preferred choice of medical professionals for imaging and diagnosis, and is used by various medical specialists like cardiologists, ophthalmologists and oncologists.

In cardiology, OCT is used for imaging coronary arteries to see vessel wall lumen morphology and microstructure at 10 times higher resolution than any other existing imaging method. A fiber-optic catheter of approximately 1 mm diameter is used to access the artery and obtain images at a resolution of approximately 15 micrometers. Nearly 100,000 intracoronary optical coherence tomography procedures are performed every year, and evidence indicates that intracoronary OCT helps physicians to optimize percutaneous coronary intervention (PCI) for treatment of myocardial infarctions. It allows highly accurate assessment of vessel lumen area, wall microstructure, intracoronary stent apposition and expansion. OCT is also better suited to visualize coronary plaque erosion, fibrotic caps overlying atheromas and trace calcium in the blood vessel walls, making it ideal for guiding complex interventional procedures in vessels with superficial calcification.