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Computational fluid dynamic (CFD) simulations can help to understand the hemodynamics of the retinal vascular network and the microcirculation. Systemic diseases, like hypertension and diabetes, change the geometry of the vasculature in the retina and these changes can be seen with fundus photography. Furthermore, these changes are indicators of cardiovascular diseases. The aim of this study is to create a plane 2D model of the retinal arterial network based on a high-resolution fundus photograph and to perform a CFD simulation. The blood vessels were segmented from the image with the Frangi filter method. A structural fractal tree was implemented to calculate the outflow boundary conditions representing the peripheral vascular bed. With the Frangi filter method and the high-resolution fundus image a comprehensive model of the visible retinal artery network could be achieved. The simulation results show realistic velocity and pressure distributions of the retinal blood flow in a healthy retina compared to in-vivo measurements in the literature. This work is an initial step towards creating comprehensive patient-specific models of the retinal vasculature based on readily available fundus photography.

Alzheimer‘s Disease is the most common form of dementia. The morphological correlate for the associated neuro damage is a synaptic loss which appears as a reduction of the dendritic spines along the dendrites of neurons. Therefore research on neural damage associated with Alzheimer‘s Disease requires the counting of large numbers of spines, which currently is performed by hand.

Surface enlargement and membrane properties have major impact on the use of materials in biological environment, e.g. for filtration, coating or wound dressing applications. This study shows the feasibility of a process combining advantages of room temperature vulcanizing silicone elastomers with the fibrous morphology achieved by an electrospinning process. Using a silicone-acetone-dilution and a heated collector, a stable process could be adjusted and first membranes were spun. Further analytics concerning morphology, hydrophobicity and protein adsorption have been evaluated. Uniform fiber membranes were spun, which show no difference in their wetting behavior compared to the film material. Due to their superior surface-to-volume ratio the spun membranes also offer a higher potential for protein adsorption.

Understanding the spontaneous protein adsorption on biomaterial surfaces is a key element to evaluate their thrombogenicity and especially their propensity to trigger the adhesion of blood platelets (thrombocytes). In this work, the adhesion of two proteins (bovine fibrinogen and bovine serum albumin) on silicone rubber and the thrombocyte adhesion on different preadsorbed protein layers has been investigated under static and dynamic flow conditions. It has been shown that proteins do not adhere equally to silicone rubber and that both the composition of protein layer and the flow conditions influence the thrombocyte adhesion.