Medical imaging designates the set of techniques that non-invasively produce images of the internal aspect of the body. As a field of scientific investigation, medical imaging constitutes a sub-discipline of biomedical engineering. It is an interdisciplinary melding of various fields including physics, mathematics, and computer science and involves multiple activities including instrumentation development, image acquisition, modeling and quantification.
Because the cornea is clear and provides a window to the retina, ophthalmic imaging can be done using a camera to photograph the retinal surface. Newer technologies developed over the past two decades allow penetration into the tissue and the reconstruction of a cross-sectional image.
First reported in 1991, optical coherence tomography (OCT) with micrometer resolution and cross-sectional imaging capabilities, has become a prominent biomedical tissue imaging technique; it is particularly suited to ophthalmic applications requiring micrometer resolution and millimeter penetration depth.