Fig. 3.

Correlation of the OCT angiogram with white-light video images. (a) and (b) are the cross-sectional reflectance and angiogram images of $12\mu \mathrm{m}$ microfluidic channels. White arrows indicate the locations of the microchannels. (c) En-face OCT angiogram of the microfluidic channels. (d) Blood flow speed was measured from video camera frames for correlation with OCT angiograms. The photograph of microfluidic channels from the upright microscope was colocalized with the en-face angiogram: the enlarged part of the angiogram at the top right corner (green square). The photo shown here was one image from a series of time-lapse images (see Video 2, mp4, 1,948 KB) [URL: http://dx.doi.org/10.1117/1.JBO.21.8.086015.2].The en-face angiogram was consistent with video images. Both results showed flow in channels 1 to 3 and no flow was detected in channel 4. (e) Relationship between syringe pump rate and blood flow speed inside the channels. Scale bars in (a and b): $100\mu \mathrm{m}$ (vertical) and $500\mu \mathrm{m}$ (horizontal). Time lapse video of microfluidic channels acquired with the upright microscope.