P2.02 IN VIVO VISUALISATION AND RECONSTRUCTION OF THE MOUSE CEREBRAL VASCULATURE USING CONTRAST ENHANCED MICRO-CT

Abstract

Introduction: Recently, a mouse model was developed showing spontaneous plaque rupture leading to stroke (ApoE−/−Fbn1C1039G+/− mouse). However, a longitudinal follow-up of these mice was hampered by the lack of an accurate in vivo method to visualize the cerebral vasculature. Methods: In this feasibility study, a female ApoE−/−Fbn1C1039G+/− and an ApoE−/− (control) mouse (stable plaques) were fed a western-type diet for up to 20 weeks. At week 10, 15 and 20 after the start of the diet CT-scans were performed before and after injection of a gold-nanoparticle contrast agent (Aurovist®, Nanoprobes, New York, USA). Image reconstruction was based on the iterative maximum-likelihood polychromatic algorithm, to reconstruct high quality images at 50-μm. Post- and pre- contrast injection images were co-registered and subtracted, using 3Dslicer, resulting in angiographic images. These images were segmented by executing a Frangi vesselness filtering, an isosurface extraction and a geodesic evolution step in VMTK. Results: It was feasible to obtain a 3D-visualisation of the mouse cerebral vasculature (see figures for the ApoE−/−Fbn1C1039G+/−mouse) up to vessels of 0.15 mm diameter. Interestingly, at week 15 and 20 contrast agent from previous injections was still present in plaques (presumably taken up by macrophages), allowing us to determine plaque position and progression over time. More severe stenosis was observed in the ApoE−/−Fbn1C1039G+/−mouse compared to the control mouse. Conclusions: The described in vivo method enabled us to generate detailed 3D reconstructions of the mouse cerebral vasculature, including presence of atherosclerotic plaques. Future work will include numerical models of the blood flow.