Figure 4.

Schematic representation of the simulation approach. Input into the model includes data on the connections, length, and initial diameter of each segment. Distributions of haemodynamic parameters (flow, shear stress, pressure) and metabolic parameters (oxygen partial pressure, PO₂) for all vessel segments are calculated.²² Next, the adaptation of individual vessel segment diameters to locally available signals derived from these haemodynamic and metabolic parameters is simulated. For some simulations, adaptation of oxygen consumption is included. After each time step, the calculation of network haemodynamics and oxygen distribution is repeated with updated vessel diameters. This iteration is repeated until convergence is achieved. Finally, functional network parameters (oxygen deficit, coefficient of variation of the shear stress, pathway length, overall energy demand and consumption, heterogeneity of flow and PO₂) are calculated.