A numerical approach to patient-specific cerebral vasospasm research.
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.


METHODS
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.


RESULTS
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.
Bioengineering Institute, University of Auckland, Auckland, New Zealand. harvey.ho@auckland.ac.nz
Harvey
H
Ho
Changwei
C
Zhang
Xiaodong
X
Xie
Peter
P
Hunter
D015901:Angiography, Digital Subtraction / Q000379:methods; D001783:Blood Flow Velocity / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008875:Middle Aged; D013345:Subarachnoid Hemorrhage / Q000150:complications; D014057:Tomography, X-Ray Computed / Q000379:methods; D020301:Vasospasm, Intracranial / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology*