Alberta Stroke Program Early CT score (ASPECTS) is widely used as cut-off point to indicate thrombolysis therapy in acute ischemic stroke. Its role in predicting patients likely to benefit from endovascular therapy has not been defined yet. ASPECTS presents a poor interrater reliability, and an automated software (eASPECTS) has been recently created to solve this limitation. Our aim was to evaluate correlation between ASPECTS measured by neurorradiologists, eASPECTS and cerebral blood volume (CBV) lesion, as well as to determine the impact of ASPECTS and eASPECTS on final infarct in thrombectomy patients.
Methods: Consecutive patients with acute intracranial ICA and proximal MCA (M1) occlusion who underwent endovascular thrombectomy were included. ASPECTS and e-ASPECTS on basal non-contrast CT were evaluated. Admission infarct core was measured on CBV in CT perfusion. We assessed time from symptom onset to neuroimaging evaluation and recanalization (TICI 2b-3) after thrombectomy. Infarct volume was measured on 24-hour control CT.
Results: We included 214 patients (88% with MCA occlusion). Median NIHSS was 18 (IQR 14-20) and mean time from symptom onset to CT was 194.11±154.34 min. Complete recanalization rate was 80.84%. Median ASPECTS was 9 (IQR 8-10) and median eASPECTS 9 (IQR 7.75-10), mean CBV infarct core was 55.29±90cc. Correlation (rs) between ASPECTS and eASPECTS was 0.44 (p<0.01). ASPECTS/eASPECTS and CBV presented a significant correlation only after 180 min of symptom onset (rs=-0.44, p<0.01 / rs=-0.26, p<0.05). Both ASPECTS and eASPECTS (rs=-0.40 and -0.43) correlated with 24h infarct volume in patients with complete recanalization (p<0.01). A logistic regression analysis showed that both ASPECTS (OR 0.56, p<0.01, CI 0.43-0.72) and eASPECTS (OR 0.57, p<0.01, CI 0.44-0.73) predicted independently low final infarct volume, together with recanalization (OR 4.6, p=0.03, CI 1.69-2.34).
Conclusions: Correlation of ASPECTS and eASPECTS with CBV was time-dependent as both measurements correlated with CBV when time to CT was>180 min. Both ASPECTS and eASPECTS predicted infarct volume after thrombectomy.