Artificially created cortical functional blood unit

Many questions regarding cerebral hemodynamics and control of cerebral blood flow remain unanswered due to the complex architecture of the cerebral vascular network. The cortical blood supply is managed by functional blood units, which form clusters of a single draining vein surrounded by a ring of three to six arterioles. Our image is the result of collaboration between a computer science student specializing in scientific visualization and a bioengineering student with research interests in cerebral blood flow. The center of this image depicts an artificially generated three-dimensional representation of a functional blood unit embedded in the human cortex. The feeding ring arterioles and draining vein were generated with a stochastic algorithm that constructed acyclic binary trees with minimum blood volume. The capillaries were created with three-dimensional Voronoi tessellation in order to achieve a mesh-like network. Our artificial network is similar in morphology to a human functional blood unit. The color-coding depicts a snapshot of a tracer's intensity after its injection into the ring arterioles. The shown tracer concentration was computed with large-scale sparse linear algebra for solving the transient convection species transport and blood flow equations. Custom coded OpenGL allows for real-time rendering of the network structure and tracer dispersion.