ARVO Annual Meeting Abstract | June 2015
To investigate a custom, non-mydriatic, handheld imaging device designed to non-invasively capture vessel-specific retinal blood flow (RBF).
This investigational device is comprised of a dual-illumination, custom imaging instrument utilizing a combination of laser speckle contrast imaging (LSCI) and indirect ophthalmoscopy. Five adult Wistar rats were anesthetized with a xylazine-ketamine mixture for retinal imaging. The device was held by the operator with the elbow stabilized. Once focusing was achieved in white light illumination, ten fundus photographs were rapidly acquired. The illumination was then changed to red laser illumination and 160 sequential speckle image frames of the same field of view (FOV) were acquired in rapid succession (at 100 frames/second). Images of both eyes were acquired, capturing the optic nerve head and peripheral retina, providing 4 sets of images per animal. The acquired raw speckle images were processed to generate LSCI images, from which vessels were segmented manually (gold standard) and automatically (using custom software) to extract intravascular RBF using LSCI-based estimates of blood velocity and diameter.