Trans arachnoid microscope integrated OCT scan of sylvian veins.

A light microscopic image of Sylvian fissure after right fronto lateral craniotomy. Opened segment shows Sylvian fissure with superficial Sylvian veins and temporal as well as frontal brain cortex. Orange line indicates region of scan. B OCT-scan of Sylvian veins. C + D enlarged excerpt of OCT scan demonstrating characteristics of OCT scans of the Sylvian fissure. E schematic drawing of microstructures as depicted by OCT: 1 thick arachnoid barrier cell membrane, 2 fading transition of arachnoid barrier cell membrane to trabecular system, 3 arachnoid blood vessels, 4 vessel wall of Sylvian vein. Note mono layered composition in OCT scan, 5 intraluminal scattering of light, 6 trabecular system. See https://osf.io/a3gx8/ for raw 3-D OCT scan.</p

OCT scan of ICA with arteriosclerotic vessel wall modification.

A Light microscopy of internal carotid artery demonstrating arteriosclerotic modifications. Orange line indicates region of OCT scan. B Corresponding OCT-scan. Note the three layered composition of the vessel wall. C + D enlarged excerpt of OCT scan. E corresponding schematic drawing of microstructures. 1 tunica externa 2 tunica media 3 tunica interna 4 arteriosclerotic segment of vessel wall with intima hyperplasia, increased vessel wall thickness and bulging of vessel wall. 5 circular inclusions could reflect an artheroma. See https://osf.io/a3gx8/ for exemplary raw 3-D OCT scan].</p

OCT scan of arterial vasospasm of MCA M2 segment.

A-C Bird’s eye view of 3-dimensional OCT volume scan of cerebral artery vasospasm; MCA, M2 segment. Orange arrow demonstrates blood flow direction; red lines represent the position of sectional OCT scans. D pre-, E intra- and F post-stenotic section. The E intra-stenotic reduction of vessel diameter is interpreted as local vasoconstriction caused by contracted smooth muscle cells of tunica media. This is illustrated by an increased diameter of tunica media in the E intra-stenotic segment in comparison to the D pre- and F post-stenotic segments. The mainly D pre- and also F post-stenotic intraluminal scattering of light could be a result of turbulent blood flow in comparison to a laminar flow in the center of the blood vessel.</p