Table 1.

Clinical definitions of ischemic core and penumbra that are currently implemented in varying commercially available perfusion software packages. CBF cerebral blood flow, CBV cerebral blood volume, MTT mean transit time, and TTP/Tmax time to peak. Values relative to the opposite hemisphere are indicated by an “r”

Software	Ischemic core	Penumbra
IntelliSpace Portal (Philips Healthcare)	CBV < 2.0 mL/100g & rMTT > 150%	rMTT > 150%
Syngo.via (Siemens Healthineers)	CBV < 1.2 mL/100g	CBF < 27.0 mL/100g/min
Vitrea (Toshiba/Canon Medical Systems)	rCBV < 41%	TTP > 6.8 s
RAPID (iSchemaView)	rCBF < 30%	Tmax > 6 s