Experimental focal XXXX in @entity468 : changes in multimodality evoked potentials as related to local cerebral blood flow and ischemic brain edema.

@entity432 @entity468 @entity2500 @entity63
Somatosensory and auditory evoked cortical potentials (SEP's and AEP's), regional cerebral blood flow, regional brain water content, and alteration of the blood-brain barrier were investigated in 3 cortical areas during permanent and 1- and 2-hour transient @entity432 of the left middle cerebral artery and after restoration of blood flow in @entity468 . During @entity432 , blood flow in the auditory cortex was severely suppressed. In the fore limb projection area of the somatosensory cortex, blood flow was moderately reduced while it was nearly unaffected in the hind limb projection area. Despite different degrees of @entity63 in the 3 cortical areas, all evoked responses were completely abolished within 10 minutes after @entity432 . During @entity432 , the pattern of blood flow reduction persisted, and all evoked potentials stayed abolished. Recirculation after @entity432 restored blood flow rapidly. AEP's recovered poorly after both 1 and 2 hours of @entity63 . SEP's regained normal amplitudes soon after recirculation in the group with 1-hour @entity432 . After 2 hours of @entity63 , the recovery of SEP's was variable but better than that of the AEP's. Remarkable water accumulation was observed in the auditory cortex of all 3 groups and was accompanied in the 2-hour @entity63 group by a disruption of the blood-brain barrier. In the 2-hour group, water accumulation was also found in the subcortical white matter radiation, whereas significant changes in regional water content were not observed in the somatosensory areas. The present study indicates that abolition of SEP's during @entity2500 in @entity468 is caused by lesions in the afferent pathway leading to cortical deafferentation rather than by cortical @entity63 .(ABSTRACT TRUNCATED AT 250 WORDS)
