OCT

OCT

Optical coherence tomography (OCT) is an optical signal acquisition and processing method. It captures micrometer-resolution, three-dimensional images from within optical scattering media (e.g., biological tissue). Optical coherence tomography is an interferometric technique, typically employing near-infrared light. The use of relatively long wavelength light allows it to penetrate into the scattering medium. Confocal microscopy, another optical technique, typically penetrates less deeply into the sample but with higher resolution. Depending on the properties of the light source (superluminescent diodes, ultrashort pulsed lasers and supercontinuum lasers have been employed), optical coherence tomography has achieved sub-micrometer resolution (with very wide-spectrum sources emitting over a ~100 nm wavelength range). Optical coherence tomography is one of a class of optical tomographic techniques. A relatively recent implementation of optical coherence tomography, frequency-domain optical coherence tomography, provides advantages in signal-to-noise ratio, permitting faster signal acquisition. Commercially available optical coherence tomography systems are employed in diverse applications, including art conservation and diagnostic medicine, notably in ophthalmology where it can be used to obtain detailed images from within the retina.

Selected Applications

Optical coherence tomography is an established medical imaging technique. It is widely used, for example, to obtain high-resolution images of the anterior segment of the eye and the retina, which can, for example, provide a straightforward method of assessing axonal integrity in multiple sclerosis, as well as macular degeneration. Research indicates that OCT may be a reliable tool for monitoring the progression of glaucoma.