Which term describes the redistribution of cerebral blood flow from normal tissue to ischemic tissue?

Which term describes the redistribution of cerebral blood flow from normal tissue to ischemic tissue?

• A. Ischemic penumbra
• B. Vasoparalysis
• C. Robin Hood phenomenon
• D. Luxury perfusion

Answer: (C)

The question hinges on how blood flow redistributes during cerebral ischemia. The best term is the Robin Hood phenomenon, which describes blood flow being redirected from normal, well-perfused brain tissue to ischemic tissue. When ischemic areas dilate their vessels and lower resistance, they pull more blood, effectively “stealing” perfusion from healthy tissue. This helps keep the vulnerable ischemic region—the penumbra—alive, but it leaves surrounding normal tissue relatively underperfused. Ischemic penumbra refers to the tissue around the infarct that is at risk but still viable, not the mechanism of redistribution itself. Luxury perfusion describes a post-reperfusion surge in blood flow that exceeds metabolic needs, not the redistribution from healthy tissue to ischemic tissue. Vasoparalysis denotes loss of cerebral autoregulation, causing CBF to follow systemic pressures rather than staying constant, which is a different aspect of cerebral blood flow control.

The question hinges on how blood flow redistributes during cerebral ischemia. The best term is the Robin Hood phenomenon, which describes blood flow being redirected from normal, well-perfused brain tissue to ischemic tissue. When ischemic areas dilate their vessels and lower resistance, they pull more blood, effectively “stealing” perfusion from healthy tissue. This helps keep the vulnerable ischemic region—the penumbra—alive, but it leaves surrounding normal tissue relatively underperfused.

Ischemic penumbra refers to the tissue around the infarct that is at risk but still viable, not the mechanism of redistribution itself. Luxury perfusion describes a post-reperfusion surge in blood flow that exceeds metabolic needs, not the redistribution from healthy tissue to ischemic tissue. Vasoparalysis denotes loss of cerebral autoregulation, causing CBF to follow systemic pressures rather than staying constant, which is a different aspect of cerebral blood flow control.