A differential detailed diffusion-weighted imaging-ASPECTS for cerebral infarct volume measurement and outcome prediction.

BackgroundDiffusion-weighted imaging-Alberta Stroke Program Early Computed Tomography Score (DWI-ASPECTS) has been used to estimate infarct core volume in acute stroke. However, the same and indiscriminate score deduction for punctate or confluent DWI-high-intensity lesion might lead to variation in performance.AimsTo develop and evaluate a differential detailed DWI-ASPECTS method in comparison with the conventional DWI-ASPECTS in core infarct volume measurement and clinical outcome prediction.MethodsWe retrospectively recruited patients with acute ischemic stroke (AIS) treated with endovascular treatment between April 2013 and October 2019. In differential detailed DWI-ASPECTS, restricted diffusion lesion that was punctate or less than half of a cortical region (M1- M6) would not lead to subtraction of point. A favourable outcome was modified Rankin score ≤2 at 90 days after stroke onset.ResultsAmong 298 AIS patients, mean age was 75 years (IQR 67-82), and 194 patients (65%) were males. Mean infarct core volume was 11ml (IQR 3-37). Overall, the score by detailed DWI-ASPECTS was significantly higher than conventional DWI-ASPECTS (8 (7-9) vs 7 (5-9); P<0.01). The detailed DWI-ASPECTS resulted in a higher correlation coefficient (r) for core infarct volume estimation than the conventional DWI-ASPECTS (r = 0.832 vs 0.773; P<0.01). Upon re-classification of those scored ≤ 6 in conventional DWI-ASPECTS (n=134) by detailed DWI-ASPECTS, the rate of favourable outcome in patients with detailed DWI-ASPECTS > 6 was significantly higher than those with ≤ 6 (29 (48%) vs 14 (19%) p<0.01).ConclusionsDetailed DWI-ASPECTS appeared to provide a more accurate infarct core volume measurement and clinical outcome correlation than conventional DWI-ASPECTS among AIS patients treated with endovascular therapy.