Volumetric imaging of microcirculations in human retina and choroids in vivo by optical micro-angiography

摘要

A new noninvasive optical angiography, optical micro-angiography (OMAG), is recently developed. Three-dimensional flow image has been performed with Optical Angiography. The bulk motion artifacts caused by the bulk motion movement were eliminated by compensating phase varieties with Doppler shift due to the bulk motion. This method enhanced the quality of flow image greatly and has the capability of resolving three dimensional (3-D) distribution of dynamic blood perfusion at the capillary level within microcirculatory beds in vivo. The imaging contrast of blood perfusion is based on the endogenous light scattering from the moving blood cells biological tissue; thus no exogenous contrasting agents are necessary. In this paper, we presented the application of this method to visualize the 3D vasculature of ocular vessels for in vivo human retinal imaging. Depth-resolved volumetric views of the retina and choroid vasculatures are also obtained by 1) segmenting the retina and choroid layers from the OCT micro-structure images to produce two masks, 2) apply the resulted two masks onto the 3D flow image to result en-face projection views of the blood vessel networks in retina and choroid. We compare the results with those from Doppler OCT and optical coherence angiography, and show that OMAG delivers superior imaging performance.