Experimental model of brainstem stroke in rabbits via endovascular occlusion of the basilar artery.
BACKGROUND
Basilar artery thrombosis remains a significant clinical problem, and no reproducible animal model has been established to study the stroke within the vertebrobasilar distribution. We report a study designed to pilot test a novel model of brainstem stroke in rabbits, created by selective endovascular occlusion of the basilar artery.


METHODS
Basilar artery occlusion was induced in 8 New Zealand white rabbits by injection of the autologous clot through the microcatheter positioned within the distal vertebral artery. Animals were divided into subgroups (I and II) based on the length of produced ischemia (3 and 6 hours, respectively). Magnetic resonance (MR) imaging of the brain and MR angiography of the intracranial vessels were performed before the procedure, and at 3 hours after induced ischemia for groups I and II, with continued imaging up to 6 hours for group II, with diffusion-weighted images acquired approximately every 30 minutes. Animals were killed at the end of the 3-hour (group I) or 6-hour (group II) ischemia time.


RESULTS
Brainstem stroke was successfully induced in all animals, with pathological changes documented in all cases. The earliest changes of ischemia on MR diffusion-weighted images were identified at only 4.5 hours of basilar artery occlusion.


CONCLUSIONS
These results suggest that a reproducible model of brainstem stroke can be induced in rabbits using selective endovascular occlusion of the basilar artery. The availability of such a model, integrated with state-of-the-art imaging techniques, holds promise for preclinical investigations of emergent therapeutic approaches in stroke.
Amiridze
Nana
N
Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA. namiridze@umm.edu
Gullapalli
Rao
R
Hoffman
Gloria
G
Darwish
Ribal
R
D000818:Animals; D001369:Axons / Q000473:pathology; D001488:Basilar Artery / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D001804:Blood Transfusion, Autologous / Q000379:methods; D002545:Brain Ischemia / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D001933:Brain Stem / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology; D020526:Brain Stem Infarctions / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology; D002404:Catheterization; D038524:Diffusion Magnetic Resonance Imaging; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D020767:Intracranial Thrombosis / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology; D018810:Magnetic Resonance Angiography; D008297:Male; D008928:Mitochondria / Q000473:pathology / Q000648:ultrastructure; D011817:Rabbits; D014656:Vascular Surgical Procedures / Q000295:instrumentation / Q000379:methods; D014715:Vertebrobasilar Insufficiency / Q000209:etiology* / Q000473:pathology* / Q000503:physiopathology