An Endovascular Canine Middle Cerebral Artery Occlusion Model for the Study of Leptomeningeal Collateral Recruitment

Abstract

This work aimed to refine a large animal in minimally invasive reversible middle cerebral artery (MCA) occlusion (MCAO) model to account for leptomeningeal collateral formation. An angiographically based methodology allowed for transient MCA and carotid terminus occlusion in 12 mongrel dogs and assessment of pial collateral recruitment. Outcome measures included 1- and 24-hour magnetic resonance imaging-based infarct volume calculation, a behavioral scale and histopathologic sections. MCAO succeeded in 8 of 12 dogs (67% efficiency). One-hour postreperfusion infarct volume predicted 24-hour postreperfusion infarct volume (r = 0.997, P < 0.0001). Pial collateral recruitment varied with time and reproducibly assessed predicted infarct volume on 1-hour postreperfusion mean diffusivity maps (P < 0.0001; r = 0.946) and 24-hour fluid-attenuated inversion recovery FLAIR magnetic resonance imaging (P = 0.0033; r = 0.961). The canine stroke scale score correlated with infarct volumes and pial collateral score. This canine MCAO model produces defined cerebral infarct lesions whose volumes correlate with leptomeningeal collateral formation and canine behavior.