Abstract 2840: Aspect Score: DWI or CT Scan, Which One Is Better Marker For Stroke Morbidity And Outcome?
Background and Objective The Alberta Stroke Program Early CT Score (ASPECTS) is a validated grading system to assess ischemic changes on CT in acute ischemic stroke. Magnetic resonance imaging with diffusion weighted imaging (DWI) sequence is commonly used to identify the final ischemic changes. We examined the difference between the relationship of NIHSS at admission and ASPECT score calculated using CT scan versus MRI DWI sequence.
Methods We conducted a retrospective analysis of prospectively collected data from 99 cases of acute ischemic stroke treated with IV rt-PA by time criteria, admitted to Mayo Clinic from March, 2002 through June, 2011. CT head at 24 hours and MRI DWI sequence were used to assign ASPECT score. We dichotomized ASPECTS (categorized as 0 to 7 versus 8 to 10) and favorable patient outcome at 3 month (modified Rankin score less than equal to 2 and more than 2). Univariate analysis including t-test, Chi-square, and Fisher Exact test was used when appropriate.
Results Mean age was 70±14 years. Mean admission NIHSS score was 8±4. DWI ASPECTS (p<0.001) and CT ASPECTS (p=0.127) were inversely associated with admission NIHSS. Higher (8-10) CT ASPECTS (p=0.001) or DWI ASPECTS (p=0.002) were associated with good outcome (mRS ≤2) at 3 months. Sensitivity, specificity, positive predictive value and negative predictive value for good outcome identified by CT ASPECTS versus DWI ASPECTS were 81% vs 52%, 54% vs 54%, 83% vs 59% and 50% vs 47% respectively.
Conclusion CT and MRI DWI are comparably useful to calculate the ASPECTS for estimation of functional outcome, but CT scan at 24 hours may be more sensitive for the prediction of good recovery.
- © 2012 by American Heart Association, Inc.