Regional very low cerebral blood volume predicts hemorrhagic transformation better than diffusion-weighted imaging volume and thresholded apparent diffusion coefficient in acute ischemic stroke.
OBJECTIVE
Currently, diffusion-weighted imaging (DWI) lesion volume is the most useful magnetic resonance imaging predictor of hemorrhagic transformation (HT). Preliminary studies have suggested that very low cerebral blood volume (VLCBV) predicts HT. We compared HT prediction by VLCBV and DWI using data from the EPITHET study.


METHODS
Normal-percentile CBV values were calculated from the nonstroke hemisphere. Whole-brain masks with CBV thresholds of the <0, 2.5, 5, and 10th percentiles were created. The volume of tissue with VLCBV was calculated within the acute DWI ischemic lesion. HT was graded as per ECASS criteria.


RESULTS
HT occurred in 44 of 91 patients. Parenchymal hematoma (PH) occurred in 13 (4 symptomatic) and asymptomatic hemorrhagic infarction (HI) in 31. The median volume of VLCBV was significantly higher in cases with PH. VLCBV predicted HT better than DWI lesion volume and thresholded apparent diffusion coefficient lesion volume in receiver operating characteristic analysis and logistic regression. A cutpoint at 2 mL VLCBV with the <2.5th percentile had 100% sensitivity for PH and, in patients treated with tissue plasminogen activator, defined a population with a 43% risk of PH (95% CI, 23% to 66%, likelihood ratio=16). VLCBV remained an independent predictor of PH in multivariate analysis with traditional clinical risk factors for HT.


CONCLUSIONS
VLCBV predicted HT after thrombolysis better than did DWI or apparent diffusion coefficient volume in this large patient cohort. The advantage was greatest in patients with smaller DWI volumes. Prediction was better in patients who recanalized. If validated in an independent cohort, the addition of VLCBV to prethrombolysis decision making may reduce the incidence of HT.
Campbell
Bruce C V
BC
Department of Neurology, Royal Melbourne Hospital, Grattan Street, Parkville VIC 3050, Australia.
Christensen
Søren
S
Butcher
Kenneth S
KS
Gordon
Ian
I
Parsons
Mark W
MW
Desmond
Patricia M
PM
Barber
P Alan
PA
Levi
Christopher R
CR
Bladin
Christopher F
CF
De Silva
Deidre A
DA
Donnan
Geoffrey A
GA
Davis
Stephen M
SM
D000368:Aged; D000369:Aged, 80 and over; D001810:Blood Volume / Q000502:physiology*; D002545:Brain Ischemia / Q000175:diagnosis / Q000503:physiopathology*; D002543:Cerebral Hemorrhage / Q000175:diagnosis / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D038524:Diffusion Magnetic Resonance Imaging; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020521:Stroke / Q000175:diagnosis / Q000503:physiopathology*