Mathematical modeling of AVM physiology using compartmental network analysis: theoretical considerations and preliminary in vivo validation using a previously developed animal model.

The development of computer modeling technique of cerebral arteriovenous malformations using circuit network analysis, validated with a previously developed animal model is presented. Such a malformation and its vascular connections are rendered into a complex system of interconnecting tubes, which is then simulated by an analogous electrical circuit using commercially available computer software. This methodology was tested using a swine model, of which a detailed computer model was constructed from anatomic and angiographic measurements of the cranial vessels. Flow conditions, before and after creation of the in vivo model, were predicted from the computer model and compared with previously reported in vivo measurements. Detailed analysis of flow within the CAVM nidus was also performed. There was a good correlation between the computer and in vivo models regarding changes in flow and pressure drop across the rete. Flow mapping within the nidus showed localized directional flow that was determined by global inputs, consistent with functional compartmentalization. This method of computer modeling appears promising for studying clinically relevant aspects of cerebral arteriovenous malformation pathophysiology. To our knowledge it is the first computer model to demonstrate functional compartmentalization.