Optical coherence tomography (OCT): a review

This paper reviews the state of the art of opti- cal coherence tomography (OCT), an interferometric imaging technique that provides cross-sectional views of the subsurface microstructure of biological tissue. Following a discussion of the basic theory of OCT, an overview of the issues involved in the design of the main components of OCT systems is presented. The review concludes by introducing new imaging modes being developed to extract additional diagnostic information. HE APPLICATION of optical technology in medicine and biology has a long and distinguished history. Since the 18th century, the microscope has been an indispensable tool of biologists. With the invention of the laser in the early 1960's, physicians gained a new surgical instrument. The development of fiber optics led to the manufacture of endoscopes that permit direct viewing of internal organs deep in the body. In the modern clinical laboratory, new optical technologies facilitate the chemical analysis of tissue samples and the counting and sizing of blood cells. In spite of these and other advances, few of the optical instruments used in medicine today take advantage of the coherent properties of light. Even most instruments that employ lasers, the ultimate