Optical coherence tomography (OCT) is a method for imaging biological tissue. The medical imaging received a boost with the advent of this new technology. It is a very recently demonstrated optical interferometric technique, the most sensitive optical imaging modality for non-invasive investigative medical imaging in vivo. Besides the use of IR light for imaging, its uniqueness is that the axial resolution is independent of the transverse resolution. The axial resolution for OCT is determined not by the “numerical aperture” of the imaging optics but by the “coherence length” of the incident light. This technology has been particularly promising for ophthalmology. However, many other domains of medical science also see OCT as a potential diagnostic tool.