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Seminar Announcement

Professor Rudolf Graf: Imaging of Acute and Subacute Ischemic Stroke - Focus on Spreading Depolarisations

4.00pm (refreshments from 3.30pm)
Tuesday 16th February 2010

Michael Smith Lecture Theatre, Michael Smith Building

For more information or to register, please go to:
www.bii.manchester.ac.uk/aboutus/events

The team at Max Planck Institute for Neurological Research, Cologne, Germany; led by Professor Graf have been studying the spontaneous suppression of cerebral blood flow (CBF) that occurs in episodes after the initial onset of stroke. The linkage of these events with electrical phenomena in the brain has been studied by using a number of measurement and imaging methods, such as Laser Speckle Flowmetry (LSF) real-time imaging and repetitive PET imaging in experimental models of focal ischemia. PET allows comparison of CBF with parameters like oxygen or glucose uptake, or effects related to inflammatory responses. The team have shown that waves of depolarisation cycle repeatedly around the perimeter of ischaemic lesions in the cerebral cortex, resulting in regular periodicity of depolarisation, and enlarging the lesion with each cycle. PET results indicate that neuroinflammation occurs in the peri-infarct zone, with increase in energy demand. It is proposed that this cycling process is fundamental to the neurobiological responses to a focal brain lesion, and that this is related to data obtained from clinical monitoring of human stroke patients.

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