Which statement best describes the ischemic core on perfusion imaging?

Which statement best describes the ischemic core on perfusion imaging?

• A. The ischemic core represents irreversibly damaged tissue, while the penumbra is salvageable
• B. The ischemic core is the only tissue that can recover with treatment
• C. The penumbra is irreversibly damaged
• D. Perfusion imaging cannot distinguish core from penumbra

Answer: (A)

In acute stroke imaging, tissue is divided into the ischemic core and the penumbra. The core is the region with critically low blood flow that has already undergone irreversible injury and is unlikely to recover. The surrounding penumbra is hypoperfused but still viable; with timely reperfusion, this tissue can be saved. Perfusion imaging typically shows the core as areas with severely reduced blood flow (and often reduced blood volume), indicating irreversible damage, while the penumbra shows delayed perfusion (end of the perfusion deficit with prolonged Tmax/MTT) but preserved blood volume, indicating tissue at risk that can be salvaged. Therefore, the statement that the ischemic core is irreversibly damaged and the penumbra is salvageable best describes what perfusion imaging reveals. The other ideas aren’t accurate: the core isn’t the only tissue that can recover, since the penumbra can be saved with treatment; the penumbra isn’t irreversibly damaged; and perfusion imaging does help distinguish core from penumbra rather than being unable to distinguish them.

In acute stroke imaging, tissue is divided into the ischemic core and the penumbra. The core is the region with critically low blood flow that has already undergone irreversible injury and is unlikely to recover. The surrounding penumbra is hypoperfused but still viable; with timely reperfusion, this tissue can be saved.

Perfusion imaging typically shows the core as areas with severely reduced blood flow (and often reduced blood volume), indicating irreversible damage, while the penumbra shows delayed perfusion (end of the perfusion deficit with prolonged Tmax/MTT) but preserved blood volume, indicating tissue at risk that can be salvaged. Therefore, the statement that the ischemic core is irreversibly damaged and the penumbra is salvageable best describes what perfusion imaging reveals.

The other ideas aren’t accurate: the core isn’t the only tissue that can recover, since the penumbra can be saved with treatment; the penumbra isn’t irreversibly damaged; and perfusion imaging does help distinguish core from penumbra rather than being unable to distinguish them.