Photoelastic Stress Analysis on Patient-Specific Anatomical Model of Cerebral Artery

In this paper, we propose a novel method to develop biomimetic models using polyurethane elastomer, which has high photoelastic coefficient, and a method to analyze stress states on the model by photoelastic effect. By using this method, stress condition on vascular wall is clearly visualized on vascular fringe as rainbow-colored photoelastic pattern, and stress can be quantitatively measured from that pattern. Ideally, retardation and path length of transmitted light through the polyurethane model should be observed for photoelastic analysis. Our method has capability to observe these two parameters simultaneously. Retardation and path length were determined from RGB value of rainbow-colored photoelastic stress pattern and permeability of light, respectively. The accuracy of stress analysis was evaluated by tensile test using cylindrical polyurethane models. 5.73% error was found in the result of photoelastic stress analysis. Lastly using the model produced by new method, we could analyze stress states quantitatively on the model of cerebral artery. Consequently, our method should be valuable for not only surgical simulations but also hemodynamic studies and pathological studies.