OPTICAL COHERENCE TOMOGRAPHY

Optical coherence tomography (OCT) is an imaging technique that produces high resolution cross-sectional images of optical reflectivity. It is a non-contact, non-invasive technique that is based on the principle of low coherence interferometry. The light source for the interferometer is a compact super-luminescent diode. OCT images can be presented as either cross-sectional images or as topographic maps. In posterior segment, OCT can measure retinal thickness, show vitreoretinal interface, macula and the choroid. In anterior segment, OCT can measure central corneal thickness, depth of anterior chamber, measurement of angle of anterior chamber and evaluation of corneal cap and stromal bed feature after laser in situ keratomileusis. For Interpretation of OCT image bright colors correspond to highly reflective areas and darker colors correspond to areas of lower reflectivity. Also spectral optical coherence tomography obtains functional information on retinal blood flow. So, we can conclude that OCT is a very helpful safe imaging technique of the eye that help diagnosis and monitoring of various ocular diseases.