It is an important issue how to reproduce properly an in vivo environment in hemodynamic simulation of living organism. In this paper, we focus on modeling of outflow boundary conditions taking account of peripheral vessel network. The network of cerebral arteries is modeled including the arteries and arterioles, whose sizes can not be resolved by MRA. The peripheral resistance, compliance, and impedance are treated by one-dimensional and zero-dimensional simulations of the network. The present method is applied to two patient-specific models with or without occlusion in the cerebral arterial circle of Willis. As a result, particularly for the case with occlusion, the present method shows a significant difference in the flow rate of each artery and also improvement in flow distribution in the network comparing to the simulation with free-stream boundary condition.
