title: Perfusion computed tomography: prediction of final infarct extent and stroke outcome.
abstract: The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) has not been previously applied to perfusion CT (CTP). Five raters assigned ASPECTS to baseline noncontrast CT (NCCT), CT angiography source images (CTA-SI), CTP source images (CTP-SI), and CTP maps of cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) from 37 consecutive patients with less than 6-hour anterior circulation ischemic stroke. Major reperfusion was identified on follow-up imaging. Mean baseline ASPECTS was compared with follow-up imaging ASPECTS. Rates of favorable outcome were compared for dichotomized baseline ASPECTS. In patients with major reperfusion, mean CBV and CTP-SI ASPECTS closely predicted final infarct ASPECTS. In patients without major reperfusion, mean CBF and MTT ASPECTS best predicted final infarct ASPECTS. There were significant increases in rates of favorable outcome for CTP-SI and CBV ASPECTS of greater than 6, versus less than or equal to 6, but not for other baseline CT modalities. ASPECTS applied to CTP is more accurate at identifying the extent of reversible and irreversible ischemia and at predicting final clinical outcome than NCCTor CTA-SI.
authors.affiliation: Department of Neurology, John Hunter Hospital, and Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Parsons
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Pepper
authors.forename: Virgil
authors.initials: V
authors.lastname: Chan
authors.forename: Sabbir
authors.initials: S
authors.lastname: Siddique
authors.forename: Siva
authors.initials: S
authors.lastname: Rajaratnam
authors.forename: Grant A
authors.initials: GA
authors.lastname: Bateman
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Levi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D020520:Brain Infarction / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D002560:Cerebrovascular Circulation / Q000502:physiology; D038524:Diffusion Magnetic Resonance Imaging; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D018810:Magnetic Resonance Angiography; D008297:Male; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020521:Stroke / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D014057:Tomography, X-Ray Computed