Central conduction time in primate brain ischemia -- a study in baboons.

摘要: The relationship between central conduction time (CCT) and levels of regional blood flow were studied in 9 primates. Flows recorded both hemispheres using the method hydrogen (2 min) clearance. somatosensory evoked potentials over contralateral cortex dorsal columns, following median nerve stimulation. CCT, a measure brain's electrical conduction, was determined by difference latencies N10, (the arrival afferent volley at sensory cortex) N7 (its column). Ischemia produced transorbital occlusion right middle cerebral artery. In acute ischemic phase within 5 minute occlusion, there significant correlation change CCT decrease flow. later occlusive phase, unaltered with flows above 15 ml/100g/min. Below that level smaller decreases resulted progressively larger changes until reached where N10 disappeared or entire electrically silent. Focal ischemia had no effect on first positive deflection from (P8) negative peak response cervical region (N7). However, latency P8 increased it absent introduction hypotension, while N8 unaltered. From our measurements, appears prolongation can be related to developing ischemia, thresholds for are not dissimilar those already responses basis amplitude alterations cortex. these levels, bear parametric alteration While measurement displays only one many which induced brain, its attraction lies simplicity fact may applied relative ease clinical situation. Under circumstances, an adequately sensitive monitor brain deserves further study.