ischemic penumbra

ischemic penumbra

an area peripheral to one of ischemia where metabolism is active but blood flow is diminished.
[L. paene, almost, + umbra, shadow]

ischemic penumbra

an area of moderately ischemic brain tissue surrounding an area of more severe ischemia. Theoretically, blood flow to this area may be enhanced in order to prevent the spread of a cerebral infarction.

ischemic penumbra

Neurology An ischemic zone in the brain at risk of infarction, which lies in a 'no-man's land' between a zone of low blood flow–< 25 ml/100 mg brain tissue/min and a zone where brain tissue is undergoing necrosis–flow–< 8 ml/100 mg/min. Cf Hemorrhagic stroke.
References in periodicals archive ?
Neuroprotection refers to the concept of applying a therapy that directly affects the brain tissue to salvage or delay the infarction of the still-viable ischemic penumbra, rather than reperfusing the tissue (Jauch et al.
The inhibition of cerebral blood flow distal to the clot results in a core of dead tissue with a surrounding viable ischemic penumbra (Liebeskind, 2010).
It leaves an area of damage called an ischemic penumbra.
The time period during which brain tissue within the ischemic penumbra remains viable is debated, (17) as the transition of brain tissue from potentially reversible to irreversible injury is dependent on the severity and duration of the underlying ischemic process.
Acute treatment of stroke aims to preserve the ischemic penumbra, protect neurons against further ischemia and enhance brain plasticity to maximize recovery.
One study of diffusion and perfusion MR in venous thrombosis showed reduced cerebral blood flow and elevated mean transit time with normal ADC in affected tissue, corresponding to an ischemic penumbra without an ischemic core.
Specific topics include: burden of stroke and risk factors, implications of strike pathophysiology and the ischemic penumbra, neuroplasticity and neurorecovery, classification of stroke subtypes, neuroimaging, management of acute ischemic stroke, and medical treatment for secondary stroke prevention.
The ischemic penumbra is commonly defined by subtracting the brain region with restricted diffusion from the region associated with low cerebral blood flow.
Imaging the ischemic penumbra with 18F-fluoromisonidazole in a rat model of ischemic stroke.
Phosphodiesterase 5 inhibitor, zaprinast, selectively increases cerebral blood flow in the ischemic penumbra in the rat brain.
The central premise of acute stroke treatment is to rescue the ischemic penumbra.
Hyperbaric oxygen therapy (HBOT) can return function to the ischemic penumbra, a region of idle neurons surrounding damaged tissues, Dr.