Evaluation of Rabbit Cerebral Mini-embolic Ischemia Model with CT Perfusion

Purpose:To explore the possibility of establishing rabbit cerebral mini-embolic ischemia model through small SiO_2 grains and evaluating it with 16 row CT perfusion,and describe its CT perfusion appearance.Materials and Methods:Twenty-two New Zealand white adult rabbits,average weight 2.5kg,were selected.Their right cervical vessels were separated and about 2 ml saline with SiO_2 grains (～0.5mm)were injected into internal carotid artery(ICA)through external carotid artery(ECA).30 minutes later,CT perfusion on 16 row CT scanner was performed,the raw data were transfer to work- station for perfusion imaging.Results:Three rabbits were died during the experiment.CT perfusion examination failed in one rabbit.We got fine CBF,CBV,and MTT pictures on eighteen rabbits,and their ischemia lesions could be analyzed.Among them,fifteen rabbits were abnormal on CT perfusion maps except 3 normal which were still normal on 24 hour follow-up.5 types of abnormal perfusion were ob- served including:①Broad low perfusion on right frontal and temporal lobes;②Disseminate focal low perfusion in right temporal lobe;③Broad low perfusion in right temporal lobes and focal low perfusion in right basal ganglia;④Local low perfusion in both side of frontal and temporal lobes;⑤Broad low perfusion in right frontal and temporal lobes,basal ganglia and cerebral stem.35 lesions of abnormal perfusion appeared:35 MTT increased,32 CBF decreased and 15 CBV decreased.Conclusion:Cerebral ischemia model in rabbits can be established through injecting small SiO2 grains from ECA into ICA.CT perfusion can be used to survey the model in time and illustrated the type of ischemia model,these will provide valuable method for exploring early stage cerebral ischemia and infarction from embolus of cervical artery.