Contrast imaging is a compelling enhancement for the portable, flat panel-based brain CT scanner currently under
development at Xoran. Due to the relative low temporal resolution of flat panel detectors, enabling tomographic imaging
on such platform requires optimizing the imaging and injection protocols. A dynamic CT head phantom was designed to
facilitate this task. The Dynamic Perfusion and Angiography Model (PAM), mimics tissue attenuation in CT images,
provides physiological timing for angiography and perfusion studies, and moves fluid with properties similar to those of
blood. The design consists of an arterial system, which contains bifurcating vessels that feed into perfusion chambers,
mimicking blood flow through capillaries and smaller vessels, and a venous system, which is symmetrical to the arterial
side and drains the perfusion chambers. The variation of geometry and flow rate in the phantom provides the
physiological total time that fluid spends in the head, and the difference in material densities correlates to CT numbers
for biological tissues. This paper discusses the design of Dynamic PAM and shows experimental results demonstrating
its ability to realistically simulate blood flow. Results of dynamic imaging studies of the phantom are also presented.
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