Hyperperfusion, Hypervascularity, Enhancement

Interactive neuroradiology reference for MRI/CT distinction among flow, vessel density/structure, and BBB/interstitial leakage.

Dropdown combination explorer

Hyperperfusion

Hypervascularity

Enhancement

Quick definitions

Concept	Physiology	What it means	Typical tools
Hyperperfusion	Increased blood flow through tissue, often quantified as increased CBF and sometimes CBV	Hemodynamic state	ASL, DSC/CTP CBF-CBV-MTT-Tmax, DSA transit, SPECT/PET
Hypervascularity	Increased vessel number, caliber, blood volume, shunt burden, or tumoral vascular architecture	Structural vascular abundance	CTA/MRA, DSA, SWI/T2 flow voids, CBV-heavy perfusion metrics, vessel wall/4D techniques
Enhancement	Accumulation of contrast in intravascular or extravascular-extracellular space due to vascularity and/or barrier disruption	Contrast behavior, not synonymous with flow	Post-gadolinium T1 MRI, post-iodine CT, DCE permeability imaging

Flow chart

1. Is enhancement present?

YESAsk whether it is predominantly intravascular, interstitial/leaky, or both.

NOBarrier may still be intact despite high flow or rich vascularity.

2. Is hyperperfusion present?

YESThink increased tissue blood delivery, shunt physiology, luxury perfusion, angiogenic tumor, seizure, AVM/dAVF, reperfusion, inflammatory hyperemia.

NOEnhancement without hyperperfusion suggests permeability/leakiness may dominate over flow.

3. Is hypervascularity present?

YESThink increased vessel density/caliber, arterial feeders, tumor neovasculature, AV shunt, pial supply, capillary-rich lesion.

NOHyperperfusion without obvious hypervascularity may reflect vasodilation or transient physiologic hyperemia.

4. Integrate pattern

Perfusion + vascularity + enhancement→Angiogenic and leaky lesions or shunting lesions with disrupted barrier.

Perfusion + vascularity without enhancement→Vascular-rich but relatively non-leaky lesions/shunts.

Perfusion + enhancement without vascularity→Transient hyperemia with BBB injury/permeability.

Vascularity + enhancement without hyperperfusion→Vessel-rich lesion with slow flow or mainly permeability-driven enhancement.

Enhancement only→Barrier breakdown/inflammation/post-treatment effect can dominate.

Perfusion only→Seizure/post-ictal hyperemia, autoregulatory change, reperfusion.

Vascularity only→Slow-flow vascular abundance or calcified/fibrotic vascular lesion.

None→Neither high flow, high vessel burden, nor visible leakiness.