OCT

Optical Coherence Tomography (OCT) is a non-invasive imaging test that uses light waves to take cross-section pictures of your retina, the light-sensitive tissue lining the back of the eye.

Overview

Optical Coherence Tomography (OCT) is an imaging technique that uses coherent light to capture micrometer-resolution, two- and three-dimensional images from within optical scattering media (e.g., biological tissue). It is used for medical imaging and industrial nondestructive testing (NDT).

History

The development of OCT began in 1991 with the work of David Huang at the Massachusetts Institute of Technology. The technology was first used in clinical settings in the mid-1990s.

Principle

OCT uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue structures. In conventional interferometry with long coherence length, this limits penetration into scattering media as only the light that has traveled a path difference on the order of the coherence length contributes to the signal. In OCT, this is mitigated by using a shorter coherence length of the source to limit the path difference of the light contributing to the signal to a small fraction of a millimeter.

Applications

OCT is used in several medical specialties, including ophthalmology, cardiology, and gastroenterology. In ophthalmology, OCT allows for detailed images of the retina and the anterior segment of the eye. In cardiology, OCT is used to image coronary arteries and identify areas of thin-cap fibroatheroma. In gastroenterology, OCT is used in endoscopy to diagnose and monitor diseases such as Barrett's esophagus.

See also

• Medical imaging
• Nondestructive testing
• Interferometry
• Ophthalmology
• Cardiology
• Gastroenterology