Magnetic resonance imaging: significance of early ischemic changes on computed tomography.
The significance of early ischemic changes (EICs) on CT remains controversial. MRI may provide relevant information in patients with EICs.


METHODS
EICs were assessed in patients with acute ischemic stroke. MRI was promptly performed at presentation after CT and repeated on day 1. The relationship between EICs and MRI parameters was assessed with one-way ANOVA for analysis of continuous variables and by the chi2 test for the analysis of variables with a binary outcome.


RESULTS
Fourty-eight patients underwent CT and MR imaging before treatment with recombinant tissue plasminogen activator (age: 63 +/- 14 years). EICs were graded as absent in 28 patients, <33% in 15 patients, and >33% of the middle cerebral artery (MCA) territory in 5 patients. NIHSS score was higher in patients with EICs that covered more than one third of the MCA territory (19 +/- 3) compared to those without EICs (12 +/- 5; p = 0.04). Patients who had major EICs had a larger acute lesion volume in diffusion-weighted imaging (DWI; 140 +/- 78 cm3) compared to those without EICs (33 +/- 51 cm3, p < 0.0001). Regional cerebral blood flow, regional cerebral blood volume, time to peak and mean transit time values were not significantly different in the study groups.


CONCLUSIONS
EICs reflect mainly a larger DWI lesion.
Cerebrovascular Disease Center, Hôpital Neurologique, Hospices Civils de Lyon, Lyon, France.
Laurent
L
Derex
Norbert
N
Nighoghossian
Marc
M
Hermier
Jean-Baptiste
JB
Pialat
Marlène
M
Wiart
Frédéric
F
Philippeau
Patrice
P
Adeleine
Jérôme
J
Honnorat
Jean-Claude
JC
Froment
Yves
Y
Berthezène
Paul
P
Trouillas
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002545:Brain Ischemia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000188:drug therapy; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006801:Humans; D018810:Magnetic Resonance Angiography; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D011994:Recombinant Proteins / Q000627:therapeutic use; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator