A functional replica of cerebral artery aneurysm (internal carotid artery). The 3D patient-specific geometry was reproduced using medical imaging modalities such as CT and DSA. Then, rapid prototyping techniques were utilized to produce a silicone-rubber-made vascular model, whose mechanical properties matched those of healthy human adults. In other words, the model had a functionality for realistic pulsatile flows with physiological pressure and flow rate. Herein, we introduce the flow measurement using the replica in conjunction with FLUOSTAR fluorescent particles and3D stereo PIV techniques. 

Movies showed FLUOSTAR particles (Top: left and right) and uncoated particles (Bottom: left and right) in PIV experiments. The images were original without any image enhancement. A standard CMOS high-speed camera and Nd:YLF laser (5 mJ/pulse) were utilized. As seen, FLUOSTAR ensured optical imaging in the near-wall region without any reflection if compared with uncoated particles. In other words, if one is interested in the near-wall parameter, such as wall shear stress, the FLUOSTAR provides an accurate quantitative measurement, whereas uncoated particles only for assessing bulk flow patterns.

Movies show 2D-time resolved PIVmeasurement and Stereo PIV phase-averaged 3D volume reconstruction usingFLUOSTAR microspheres. The time frequency of the former was 500 Hz, and thespatial resolution of the latter was about 100 micro millimeter. For thelatter, the 100m thin laserlight sheet scanned the whole volume of the aneurysm in a phase-locked manner,and the resulting 3C velocities were combined with the assumption ofphase-to-phase repeatability. All PIV processing was done using originalimages.  The great S-N ratioachieved by FLUOSTAR enabled to assess the detailed flow dynamics, even in thenear-wall region. 

Excellent compatibility for water. Fluostar particles were coated with hydrophilic materials, which enables to eliminate coagulation and adhesion of particles. Particles can be completely dispersed in water without any stirring or even chemical promotion. Just let particles be exposed to water. Enjoy water compatibility of Fluostar!!!