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It is assumed that cerebral homodynamics is an important factor for the cerebrovascular disorders such as subarachnoid hemorrhage. Since a blood vessel has bend and bifurcation with pulsatile blood flow, the flow structure becomes complex and in the three-dimensions. In order to obtain the information on velocity components at an orbital location and time, the stereo PIV technique is applied to measure and visualize flow in the realistic cerebral aneurysm model, which is based on the medical image data. And to discuss the difference of inflow conditions, we measure the velocity distribution at the pulsatile state and steady state.As a result of measurement at the peak systole, the velocity profiles are different. In steady flow, the flow structure along the aneurysm is observed. But in pulsatile flow, the flow that goes to top of aneurysm is observed.

It is assumed that cerebral homodynamics is an important factor for the cerebrovascular disorders such as subarachnoid hemorrhage. Since a blood vessel has bend and bifurcation with pulsatile blood flow, the flow structure becomes complex and in the three-dimensions. In order to obtain the information on velocity components at an orbital location and time, the stereo PIV technique is applied to measure and visualize flow in the realistic cerebral aneurysm model, which is based on the medical image data. Because it is difficult to place the calibration plate, the paper presents the calibration method such that laser beams create calibration points. As a result, the flow structure along the aneurysm is observed successfully.

It is assumed that cerebral homodynamics is an important factor for the cerebrovascular disorders such as subarachnoid hemorrhage. Since a blood vessel has bend and bifurcation, the flow structure is in the three-dimensions. The Stereo PIV is a suitable method for measurement of complicated flow phenomena. The Stereo PIV uses a plate in a measurement domain for calibration. However, if the domain is complicated, it is difficult to place such an object. In this research, we have presented a noninvasive calibration method using a calibration point created by laser beams.

It is important to determine whether a particular cerebral aneurysm has a high risk of rupture or not so that it can be treated before subarachnoid hemorrhage occurs. Hemodynamic stresses, especially Wall Shear Stress (WSS), are considered to play an important role in formation, growth and rupture of the cerebral aneurysm. In this paper, we investigate WSS under the pulsatile inflow conditions in a realistic in vitro model of a cerebral aneurysm. The geometry of measurement model is constructed in a patient- specific manner using CT data. The stereo PIV measurement is conducted to obtain the velocity field in the cerebral aneurysm. We calculate the WSS distribution from PIV results and geometry data of lost model. The results show that overall WSS distribution in the model does not charge uniformly with time due to palsatile flow.

Measurements of velocity/vorticity of cylinder wake by using stereo-PIV method.Three-dimensional vorticity iso-surfaces were successfully reconstructed from temporal series of velocity in a cross-sectional plane assuming Taylor's hypothesis. Vortex structure having a mode A pattern was observed at Re=1000.