Optical coherence microscopy (OCM) provides real-time, in-vivo, three-dimensional, isotropic micron-resolution
structural and functional characterization of tissue, cells, and other biological targets. Optical coherence angiography
(OCA) also provides visualization and quantification of vascular flow via speckle-based or phase-resolved techniques.
Performance assessment of neuroprosthetic systems, which allow direct thought control of limb prostheses, may be aided
by OCA. In particular, there is a need to examine the underlying mechanisms of chronic functional degradation of
implanted electrodes. Angiogenesis, capillary network remodeling, and changes in flow velocity are potential indicators
of tissue changes that may be associated with waning electrode performance. The overall goal of this investigation is to
quantify longitudinal changes in vascular morphology and capillary flow around neural electrodes chronically implanted
in mice. We built a 1315-nm OCM system to image vessels in neocortical tissue in a cohort of mice. An optical window
was implanted on the skull over the primary motor cortex above a penetrating shank-style microelectrode array. The
mice were imaged bi-weekly to generate vascular maps of the region surrounding the implanted microelectrode array.
Acute effects of window and electrode implantation included vessel dilation and profusion of vessels in the superficial
layer of the cortex (0-200 μm). In deeper layers surrounding the electrode, no qualitative differences were seen in this
early phase. These measurements establish a baseline vascular tissue response from the cortical window preparation and
lay the ground work for future longitudinal studies to test the hypothesis that vascular changes will be associated with
chronic electrode degradation.