The prolonged ischemia in the compromised environment of contused cortex, may contribute to the slow panecrosis. Other data indicate that despite the ischemia, neurons in contused cortex are viable for at least 14 days after 400 mg/cm impact. We previously reported (2) that microstimulation of contused cortex evoked appropriate movements for up to 2 weeks following TBI. Stimulation after 2 weeks was unsuccessful in evoking any movements. Together with this histological work, the data indicates that neurons in contused cortex appearing viable for days after TBI are also functional for up to two weeks following cortical contusion despite severe ischemia. Whether this is an extended "therapeutic window" when surviving neurons could be rescued from the progressive panecrosis is unknown.
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