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
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.