DWI ASPECT Scores And Infarct Volume As Predictors Of Outcome After Recanalization In Middle Cerebral Artery Stroke

Background and Purpose: Final infarct volume has previously been shown to be a major predictor of outcome after endovascular therapy for middle cerebral artery (MCA) occlusion. However, the importance of specific location of infarct within the MCA territory has not been described. We sought to assess the predictive value of specific topographic regions as predictors of outcomes in a homogeneous cohort of patients treated with endovascular therapy of M1 occlusive disease who underwent post procedure MRI. Methods: A retrospective review of our prospectively maintained single center endovascular database was performed. Automated software was used to measure infarct volume and the DWI ASPECT score was assessed by visual inspection using standard templates. Univariate and multivariate analysis was performed to determine predictors of favorable outcomes using each of the 10 regions as part of the ASPECT score as well as total ASPECT score. Results: 100 patients were identified. 56% were female. Median age was 70. Successful recanalization was achieved with TIMI 2/3 flow in 87% of patients and TICI 2B/3 in 61% of patients. Good outcomes (mRS 0-2 at 3 months) in 46% of patients. There was no difference between outcomes based on the hemisphere involved. Median final infarct on DWI MRI at 24 hours was 39 cc. Median ASPECT score was 6. In multivariate analysis, strong predictors of good outcomes included: age (OR 0.88, 95% CI 0.8-0.96, p=0.006), serum glucose on admission (OR 0.98, 95% CI 0.97-1, p=0.046) and ASPECT score on MRI (OR 0.7, 95% CI 0.03-1.05, p=0.03). There was a high correlation between the volume of infarct and ASPECT score on the post recanalization MRI (Spearman’s rho of -0.76). Conclusions: Quantitative (automated software) and semi-quantitative (ASPECT score values) measurements of infarct size are highly predictive of outcomes after recanalization therapy in middle cerebral artery infarcts. No single topographic region or combination of regions is predictive of outcome, whereas total ASPECT scores are highly predictive. These data support the role of post procedural MRI in guiding prognosis after anterior circulation infarct.