Wide field optical coherence tomography of the choroid in vivo.

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Wide field optical coherence tomography of the choroid in vivo. Invest Ophthalmol Vis Sci. 2008 Dec 5; Authors: Povazay B, Hermann B, Hofer B, Kajic V, Simpson E, Bridgford T, Drexler W Purpose. To demonstrate high speed, high axial resolution optical coherence tomography (OCT) at 1060 nm with penetration to the sclera. The clinical feasibility of dense, high-speed sampling for higher level of detail at the macula and optic nerve head are exploited in respect to motion artifacts. Methods. A 3D-OCT system employing an InGaAs camera operating at 47,000 depth scans/s was developed. Utilizing the 1010-1080 nm wavelength band leads to 6.8 microm effective axial resolution and enables acquisition of retinal and choroidal 130 Mvoxel volumes of human subjects within 7 seconds. Motion artifacts were reduced by numeric post-processing techniques. Results. Drift motion artifacts could be suppressed within fields up to 38 degrees .38 degrees (~1 cm(2)) utilizing acquisition speeds of up to 74 frames/second at 512.512 pixel/frame. This isotropic OCT sampling of the human retina in vivo allowed reconstruction of retinal microvasculature, solely on vessel reflectivity, without use of contrast agents and reveals three interconnected capillary meshworks. Simultaneously in the choroid the structure of the choriocapillaris, Sattler's and Haller's layer were differentiated and the choroidal/scleral-interface was clearly delineated in densely sampled narrow and large angle field scans (>38 degrees ). At the optic nerve head the 3D fine structure of the lamina cribrosa and the circle of Zinn-Haller were visualized. Conclusions. OCT utilizing the long wavelength side of the 1060 nm water transmission window significantly profits from lower scattering and allows investigation of the retina and choroid at an unprecedented combination of penetration, high speed at high resolution and might provide superior clinical feasibility to commercial 800 nm devices. PMID: 19060289 [PubMed - as supplied by publisher]

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