Could clinical diffusion-mismatch determined using DWI ASPECTS predict neurological improvement after thrombolysis before 3 h after acute stroke?
BACKGROUND
Clinical-diffusion mismatch (CDM) between stroke severity and volume of diffusion-weighted imaging (DWI) lesions seems to predict penumbra. The Alberta Stroke Program Early CT Score on DWI (DWI ASPECTS) is a simple score for identifying ischaemic lesions. The authors examined whether CDM using DWI ASPECTS can predict neurological improvement in patients with acute stroke treated with intravenous tissue plasminogen activator (t-PA).


METHODS
The authors enrolled consecutive patients with anterior circulation stroke treated with intravenous t-PA. The authors calculated a cut-off value for CDM using DWI ASPECTS. After excluding a group of patients with mild symptoms (National Institutes of Health Stroke Scale (NIHSS) score <8), the authors divided the patients into two groups by presence or not of CDM (a positive group (P-CDM) and a negative group (N-CDM)). The authors then compared clinical characteristics including NIHSS score and modified Rankin Scale at 90 days after intravenous t-PA.


RESULTS
Seventy-one patients (male 41, mean age 74 years) were enrolled. DWI ASPECTS was linearly related to DWI lesion volume. The authors defined CDM as NIHSS scores > or =8 and DWI ASPECTS > or =7. The P-CDM group had 35 patients (61%) and the N-CDM group 22 patients (39%). NIHSS scores on admission were 15 (median) in P-CDM and 20 in N-CDM (p=0.004). NIHSS scores after intravenous t-PA improved in P-CDM but were unchanged in N-CDM (7 vs 20 at 7 days, p=0.033 on ANOVA). A favourable outcome at 90 days, defined as modified Rankin scale 0-3, was found in 46% of P-CDM patients and 14% of N-CDM patients (p=0.020).


CONCLUSIONS
CDM determined using DWI ASPECTS may be associated with neurological improvement in patients treated with intravenous t-PA.
Terasawa
Yuka
Y
Department of Stroke Medicine, Kawasaki Medical School, Kurashiki, Japan. tera@clin.med.tokushima-u.ac.jp
Kimura
Kazumi
K
Iguchi
Yasuyuki
Y
Kobayashi
Kazuto
K
Aoki
Junya
J
Shibazaki
Kensaku
K
Kaji
Ryuji
R
D000368:Aged; D002545:Brain Ischemia / Q000150:complications / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000188:drug therapy / Q000209:etiology / Q000473:pathology; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000145:classification / Q000188:drug therapy* / Q000473:pathology*; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000008:administration & dosage / Q000627:therapeutic use; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D010959:Tissue Plasminogen Activator