In vivo high-contrast imaging of deep posterior eye by 1-μm swept source optical coherence tomography and scattering optical coherence angiography

Retinal, choroidal and scleral imaging by using swept-source optical coherence tomography (SS-OCT) with a 1-microm band probe light, and high-contrast and three-dimensional (3D) imaging of the choroidal vasculature are presented. This SS-OCT has a measurement speed of 28,000 A-lines/s, a depth resolution of 10.4 microm in tissue, and a sensitivity of 99.3 dB. Owing to the high penetration of the 1-microm probe light and the high sensitivity of the system, the in vivo sclera of a healthy volunteer can be observed. A software-based algorithm of scattering optical coherence angiography (S-OCA) is developed for the high-contrast and 3D imaging of the choroidal vessels. The S-OCA is used to visualize the 3D choroidal vasculature of the in vivo human macula and the optic nerve head. Comparisons of S-OCA with several other angiography techniques including Doppler OCA, Doppler OCT, fluorescein angiography, and indocyanine green angiography are also presented.