Selective MCA occlusion: a precise embolic stroke model.

Abstract The present study describes a method for improving the precision and accuracy of clot placement within the middle cerebral artery (MCA) of rats, utilizing a micro-catheter and laser Doppler flowmetry. This technique reduces the size of clot needed to achieve stable occlusion with no failed embolizations and a low percentage of early recanalizations. Infarctions were consistent in both size and distribution within the MCA perfusion territory. Selective embolization in aged animals ( n  = 10) resulted in substantially larger infarctions than those seen in aged animals ( n  = 10) following non-selective embolization ( P n  = 10) subjected to filamentous occlusion ( P n  = 14). All aged animals surviving 24 h exhibited moderate to severe functional deficits, with selectively occluded animals having a higher mean score on the modified neurologic severity scale ( P  = 0.002). This model provides a highly reproducible method for embolization of the MCA and reliable reperfusion with rt-PA.