The basics of intravascular optical coherence tomography

Abstract

Optical coherence tomography (OCT) has opened new horizons for intravascular coronary imaging. It utilizes near-infrared light to provide a microscopic insight into the pathology of coronary arteries in vivo. Optical coherence tomography is also capable of identifying the chemical composition of atherosclerotic plaques and detecting traits of their vulnerability. At present it is the only tool to measure the thickness of the fibrous cap covering the lipid core of the atheroma, and thus it is an exceptional modality to detect plaques that are prone to rupture (thin fibrous cap atheromas). Moreover, it facilitates distinguishing between plaque rupture and plaque erosion as a cause of acute intracoronary thrombosis. Optical coherence tomography is applied to guide angioplasties of coronary lesions and to assess outcomes of percutaneous coronary interventions broadly. It identifies stent malapposition, dissections, and thrombosis with unprecedented precision. Furthermore, OCT helps to monitor vessel healing after stenting. It evaluates the coverage of stent struts by the neointima and detects in-stent neoatherosclerosis. With so much potential, new studies are warranted to determine OCT's clinical impact. The following review presents the technical background, basics of OCT image interpretation, and practical tips for adequate OCT imaging, and outlines its established and potential clinical application.

In vivo monitoring of thrombosis in mice by optical coherence tomography

“…OCT has been employed to examine thrombus morphology ex vivo . Intracoronary OCT has been developed to both identify coronary atherosclerosis, thrombus formation and plaque rupture due to its distinct resolution advantage over other imaging modalities . It has also been used to evaluate the acute and chronic result of stent implantation including thrombus detection .…”

Cardiac Imaging: OCT

“…OCT is done with a fiberoptic wire with a rotating lens emitting near infrared (1,300 nm) light and records the light reflected from the tissue. 2 Light interferometry is the technique used to analyze the reflected light signal. The result of OCT is an image of very high resolution (10 µm axially and 20 µm lateral).…”

Intracoronary Imaging in the Detection of Vulnerable Plaques

“…OCT, which uses the reflection of near-infrared light to generate an image, offers unparalleled spatial resolution (<10 μm axial; 20–40 μm lateral) and is a core intravascular imaging modality in clinical practice [ 42 , 43 ]. OCT uses a low-coherence, near-infrared light source (centre wavelength, λ o = 1.3 μm) which is directed at and reflected from the vessel wall.…”