Differentiation of the microvasculature with different blood flow speed based on variable interscan time analysis in OCT angiography skin imaging

OCT-Angiography (OCTA) images are based on the nature that light backscattered from the vascular and neighboring tissue exhibiting different temporal scattering features. Therefore, by analyzing the variation of the OCT signal intensity in the OCT images acquired at different time points, regions exhibiting blood flow can be differentiated from neighboring static tissue. When compared to conventional approach such as Doppler OCT, the quantification of blood flow with OCTA is challenging. In this paper, we built a the swept-source OCT system with a 1060 nm wavelength-swept laser providing a high imaging speed (200,000 Ascans/sec) over the biological samples. Most importantly, repetitive OCT images can be acquired at the same locations, enabling OCTA imaging with different effective interscan time with so called variable interscan time analysis (VISTA) algorithm to highlight the microvasculature with different blood flow speed. Preliminary results of the OCTA imaging of the mouse ear skin are demonstrated in this paper.