[The penumbra area]

Abstract

Introduction: Habitually, when one speaks about penumbra area it refers to an ischemic region with the risk of permanent affection but potentially recoverable, that extend during a period of 4 to 6 hours. Nevertheless, with the reperfusion we cannot always get a neurofunctional recovery, or hinder the extension of the infarct. In this work, the author checked the mechanisms that participate in the lesion of penumbra area, as far as extension, duration as well as their relation with the therapeutic windows.

Development: Penumbra is a brain tissue at risk of infarct but is potentially recoverable and receives a variable level of cerebral blood flow (diminished, normal or augmented) which presents a functional alteration principally of its metabolism that is produced by various mechanisms like phenomenon of no reflow, reperfusion injury, hemodynamics disorders, spreading depolarization, delayed neural death, deafferentation (diaschisis), postischemic exofocal neural death, slowly progressive neural damage, among other alteration different a simple lesion by energy failure, these disorders may act during several months.

Conclusion: Three therapeutics windows could be defined: one for the reperfusion (between 6 and 8 hours), another for the survival of neurons that are within the penumbra area (between 24 hour and 17 days) and a window for the neurofunctional recovery that extends itself to at least three months after a stroke.