Early ADC changes in motor structures predict outcome of acute stroke better than lesion volume.
OBJECTIVE
The lesion volume assessed from diffusion-weighted imaging (DWI) within the first six hours to first week following stroke onset has been proposed as a predictor of functional outcome in clinical studies. However, the prediction accuracy decreases when the DWI lesion volume is measured during the earliest stages of patient evaluation. In this study, our hypothesis was that the combination of lesion location (motor-related regions) and diffusivity measures (such as Apparent Diffusion Coefficient [ADC]) at the acute stage of stroke predict clinical outcome.


METHODS
Seventy-nine consecutive acute carotid territory stroke patients (median age: 62 years) were included in the study and outcome at three months was assessed using the modified Rankin scale (good outcome: mRS 0-2; poor outcome: mRS 3-5). DWI was acquired within the first six hours of stroke onset (H2) and the following day (D1). Apparent Diffusion Coefficient (ADC) values were measured in the corticospinal tract (CST), the primary motor cortex (M1), the supplementary motor area (SMA), the putamen in the affected hemisphere, and in the contralateral cerebellum to predict stroke outcome.


RESULTS
Prediction of poor vs. good outcome at the individual level at H2 (D1, respectively) was achieved with 74% accuracy, 95%CI: 53-89% (75%, 95% CI: 61-89%, respectively) when patients were classified from ADC values measured in the putamen and CST. Prediction accuracy from DWI volumes reached only 62% (95%CI: 42-79%) at H2 and 69% (95%CI: 50-85%) at D1.


CONCLUSIONS
We therefore show that measures of ADC at the acute stage in deeper motor structures (putamen and CST) are better predictors of stroke outcome than DWI lesion volume.
Rosso
C
C
Urgences cérébrovasculaires, Pitié-Salpêtrière Hospital, AP-HP, 47-83, boulevard de l'Hôpital, 75013 Paris,France; UPMC, University Paris 06, 75005 Paris, France; CRICM, UMR S_975, équipe Nemesis, Pitié-Salpêtrière Hospital, 75013 Paris, France. Electronic address: charlotte.rosso@gmail.com.
Colliot
O
O
UPMC, University Paris 06, 75005 Paris, France; CRICM, UMR S_975, équipe Nemesis, Pitié-Salpêtrière Hospital, 75013 Paris, France.
Pires
C
C
Urgences cérébrovasculaires, Pitié-Salpêtrière Hospital, AP-HP, 47-83, boulevard de l'Hôpital, 75013 Paris,France.
Delmaire
C
C
Centre for NeuroImaging Research (CENIR), Pitié-Salpêtrière Hospital, 75013 Paris, France; Department of Neuroradiology, AP-HP, CHRU Roger-Salengro, 59000 Lille, France.
Valabrègue
R
R
Centre for NeuroImaging Research (CENIR), Pitié-Salpêtrière Hospital, 75013 Paris, France.
Crozier
S
S
Urgences cérébrovasculaires, Pitié-Salpêtrière Hospital, AP-HP, 47-83, boulevard de l'Hôpital, 75013 Paris,France.
Dormont
D
D
UPMC, University Paris 06, 75005 Paris, France; CRICM, UMR S_975, équipe Nemesis, Pitié-Salpêtrière Hospital, 75013 Paris, France; Department of Neuroradiology, AP-HP, Pitié-Salpêtrière Hospital, 75013 Paris, France.
Baillet
S
S
UPMC, University Paris 06, 75005 Paris, France; CRICM, UMR S_975, équipe Nemesis, Pitié-Salpêtrière Hospital, 75013 Paris, France; Department of Neurology, Medical College of Wisconsin, 53211 Milwaukee, USA.
Samson
Y
Y
Urgences cérébrovasculaires, Pitié-Salpêtrière Hospital, AP-HP, 47-83, boulevard de l'Hôpital, 75013 Paris,France; UPMC, University Paris 06, 75005 Paris, France; CRICM, UMR S_975, équipe Nemesis, Pitié-Salpêtrière Hospital, 75013 Paris, France.
Lehéricy
S
S
UPMC, University Paris 06, 75005 Paris, France; Centre for NeuroImaging Research (CENIR), Pitié-Salpêtrière Hospital, 75013 Paris, France; Department of Neuroradiology, AP-HP, Pitié-Salpêtrière Hospital, 75013 Paris, France.
D000368:Aged; D000465:Algorithms; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000473:pathology*; D011237:Predictive Value of Tests; D011379:Prognosis; D011699:Putamen / Q000473:pathology*; D011712:Pyramidal Tracts / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D020521:Stroke / Q000473:pathology*