Doppler optical coherence tomography

Abstract

Noninvasive techniques for imaging in vivo blood flow are of great value to biomedical research and clinical diagnostics where many diseases have a vascular etiology or component. In ophthalmology, many diseases involve disturbances in ocular blood flow, including diabetic retinopathy, low tension glaucoma, anterior ischemic optic neuritis, and macular degeneration. Simultaneous imaging of tissue structure and blood flow could provide critical information for early diagnosis of ocular diseases. This chapter describes Doppler OCT, an imaging modality that combines Doppler principles with OCT to image tissue structure and blood flow velocity simultaneously. Since the first demonstration of Doppler OCT in 1997, significant advances have been made to translate the technology from bench–side to clinical applications. The development of phase–resolved methods and Fourier domain technique has significantly increased imaging speed and velocity sensitivity, and has enabled real–time imaging of tissue microcirculation. We will review the advances in Doppler OCT over the last eighteen years. Several variation of Doppler OCT techniques, such as phase variation and intensity variation methods, will be compared. The recent applications of Doppler OCT for quantifying blood flow, mapping retinal and choroidal microcirculation, and evaluating mechanical properties with optical coherence elastography will be discussed.