Klaus Affeld

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  • André Berthe, Daniel Kondermann, Carolyn Christensen, Leonid Goubergrits, bullet Christoph, Garbe bullet +2 others
  • 2009
This paper describes a new time-resolved three-dimensional, three-component (3D-3C) measurement technique called wall-PIV. It was developed to assess near wall flow fields and shear rates near non-planar surfaces. The method is based on light absorption according to Beer– Lambert's law. The fluid containing a molecular dye and seeded with buoyant particles(More)
BACKGROUND AND PURPOSE Coil embolization procedures change the flow conditions in the cerebral aneurysm and, therefore, in the near-wall region. Knowledge of these flow changes may be helpful to optimize therapy. The goal of this study was to investigate the effect of the coil-packing attenuation on the near-wall flow and its variability due to differences(More)
BACKGROUND Clinical studies suggest that local wall shear stress (WSS) patterns modulate the site and the progression of atherosclerotic lesions. Computational fluid dynamics (CFD) methods based on in-vivo three-dimensional vessel reconstructions have recently been shown to provide prognostically relevant WSS data. This approach is, however, complex and(More)
This chapter describes the development of a new time resolved 3D PIV technique for near wall flow field measurements. This measurement technique, called wall-PIV, is based on Beer-Lambert's law. It substitutes the classical PIV laser sheet by a diffuse, monochromatic full-field illumination that is limited to the near wall region by an absorbing molecular(More)
BACKGROUND Cerebral arterial vasospasm leads to delayed cerebral ischemia and constitutes the major delayed complication following aneurysmal subarachnoid hemorrhage. Cerebral vasospasm can be reduced by increased blood clearance from the subarachnoid space. Clinical pilot studies allow the hypothesis that the clearance of subarachnoid blood is facilitated(More)
—A noninvasive continuous blood pressure measurement technique that has been developed lately requires precise control of the blood flow through a superficial artery. The flow is measured using ultrasound and influenced via manipulating the pressure inside an inflatable air balloon which is placed over the artery. This contribution is concerned with the(More)
Flow fields are one of the key factors associated with the life threatening formation of thrombi in artificial organs. Therefore, knowledge of flow field is crucial for the design and optimization of a long-term blood pump performance. The blood chamber flow of a novel counterpulsation heart assist device (CPD) has been investigated using laser Doppler(More)