Search results for "Penumbra"
showing 3 items of 13 documents
Temporal and Spatial Evolution of Cortical Blood Flow in the Penumbra of Venous Infarcts
2001
A cortical venous infarction model has been evaluated regarding the temporal and spatial evolution of regional flow reduction. Two cortical veins were occluded photochemically with rose bengal and fiberoptic illumination. Seven rats served to demonstrate effects on regional cortical blood flow using laser Doppler scanning. After two-vein occlusion, there was a widespread reduction of flow that gradually deteriorated after vein occlusion when regional cortical flow in a 3.5 x 7.0 mm window: after 15 min it had decreased to 57.8% ± 8.0%, and after 75 min it was 34.3% ± 5.4%. Infarct volumes as determined in 10 rats 5 days after two-vein occlusion had an average size of 3.6 ± 0.7 mm3. The data…
Modelling of the Ischemic Penumbra
1999
What happens to the ischemic penumbra – defined as a territory of critically reduced blood flow in the close neighborhood of an ischemic core – determines outcome after stroke. Currently the pathophysiology of the penumbra is studied predominantly in rat models with occlusion of the middle cerebral artery. Here we propose two other rat models with distinct advantages. One produces a large territory of critical flow reduction in the cortex of one hemisphere without presence of an infarct core: this model is suited to study mediator mechanisms that may transform the penumbra into necrotic tissue. It is produced by occluding one carotid artery and in addition reducing arterial pressure to 50mm…