Abstract

Advances in optical technologies have spurred many new applications of light in biology and medicine. The expanding fields of optical diagnostics and therapeutics include such diverse topics as photodynamic therapy for cancers and other diseases, fluorescence endoscopy for early tumor detection, photoacoustic imaging for deep tissue vascular visualization, and optical coherence tomography (OCT) for superficial tissue assessment. OCT is a new medical imaging modality in which the coherent interference of a wide spectrum light source is used to create a high resolution (micron-scale) subsurface image of tissue microstructure. Recently, we have supplemented the microstructural OCT images with additional contrast mechanisms such as blood flow imaging using the static and dynamic (Doppler) speckle effects, which provide us the ability to perform label-free optical microangiography (OMAG) of microcirculatory tissue beds. The ability to visualize tissue blood flow at the microcirculation level is important in a variety of biomedical applications, some of which (along with the OCT basics and the enabling technologies) will be highlighted in this talk. Examples using OMAG to delineate the dynamic blood perfusion, down to capillary level resolution, within living tissues will be given, including cerebral blood flow in small animals and retinal blood flow in humans.

© 2013 Optical Society of America