1 Fabrication of 3 D Mili - Scale Channels for Hemodynamic Studies

3D mili-scale channel representing simplified anatomical models of blood vessels were constructed in polidimethylsiloxane (PDMS). The objective was to obtain a sequential method to fabricate transparent PDMS models from a mold produced by rapid prototyping. For this purpose, two types of casting methods were compared, a known lost-wax casting method and a casting method using sucrose. The channels fabricated by both casting methods were analysed by Optical Microscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). The lost-wax method is not ideal since the channels become contaminated during the removal process. The models produced with the lost-sucrose casting method exhibit much better optical characteristics. These models are transparent with no visible contamination, since the removing process is done by dissolution at room temperature rather than melting. They allow for good optical access for flow visualization and measurement of the velocity field by micro-particle image velocimetry (μPIV). The channels fabricated by the lost-sucrose casting method were shown to be suitable for future hemodynamic studies using optical techniques.