A numerical approach to patient-specific cerebral vasospasm research

Abstract

Background: Cerebral vasospasm (CVS) is a devastating sequela of subarachnoid hemorrhage (SAH). Among the many factors that are associated with the pathogenesis of CVS, the cerebral blood flow (CBF) and underlying haemodynamics play an important role. In this paper we present an integrated clinical-engineering approach to CVS research. Method: After an admission CT scan, CT angiography (CTA) and/or Digital Subtraction Angiography (DSA) scans are performed for SAH patients. The anatomy of cerebral vasculature and its geometric parameters are monitored and compared with follow-up CTA and/or DSA scans. The governing equations for blood flow are numerically solved for the arteries and the computational results are analysed. Findings: In the particular CVS case presented in this paper, the numerical results indicate that blood flow velocity increases in moderate and severely spastic vessels (A1, M1 segment) that perfuse brain tissues. However, decreased vessel diameters in A1 and M1 arteries create larger resistance to CBF and hence lead to reduced flow in the inner carotid artery (ICA). Conclusions: A numerical approach to patient-specific CVS analysis has been established, and some initial results are achieved via application to an actual spasm case. The undergoing and future work include applying the approach to more CVS cases and incorporating computational models of different scales into the current framework for CVS and SAH research. © Springer-Verlag/Wien 2011.