Abstract
PurposeWe hypothesize that the detectability of early ischemic changes on non-contrast computed tomography (NCCT) is limited in hyperacute stroke for both human and machine-learning based evaluation. In short onset-time-to-imaging (OTI), the CT angiography collateral status may identify fast stroke progressors better than early ischemic changes quantified by ASPECTS.MethodsIn this retrospective, monocenter study, CT angiography collaterals (Tan score) and ASPECTS on acute and follow-up NCCT were evaluated by two raters. Additionally, a machine-learning algorithm evaluated the ASPECTS scale on the NCCT (e-ASPECTS). In this study 136 patients from 03/2015 to 12/2019 with occlusion of the main segment of the middle cerebral artery, with a defined symptom-onset-time and successful mechanical thrombectomy (MT) (modified treatment in cerebral infarction score mTICI = 2c or 3) were evaluated.ResultsAgreement between acute and follow-up ASPECTS were found to depend on OTI for both human (Intraclass correlation coefficient, ICC = 0.43 for OTI < 100 min, ICC = 0.57 for OTI 100–200 min, ICC = 0.81 for OTI ≥ 200 min) and machine-learning based ASPECTS evaluation (ICC = 0.24 for OTI < 100 min, ICC = 0.61 for OTI 100–200 min, ICC = 0.63 for OTI ≥ 200 min). The same applied to the interrater reliability. Collaterals were predictors of a favorable clinical outcome especially in hyperacute stroke with OTI < 100 min (collaterals: OR = 5.67 CI = 2.38–17.8, p < 0.001; ASPECTS: OR = 1.44, CI = 0.91–2.65, p = 0.15) while ASPECTS was in prolonged OTI ≥ 200 min (collaterals OR = 4.21,CI = 1.36–21.9, p = 0.03; ASPECTS: OR = 2.85, CI = 1.46–7.46, p = 0.01).ConclusionThe accuracy and reliability of NCCT-ASPECTS are time dependent for both human and machine-learning based evaluation, indicating reduced detectability of fast stroke progressors by NCCT. In hyperacute stroke, collateral status from CT-angiography may help for a better prognosis on clinical outcome and explain the occurrence of futile recanalization.
Highlights
Mechanical thrombectomy (MT) is a successful and effective treatment in acute ischemic stroke due to large vesselocclusion [1, 2]
We propose that the collateral status may fill the diagnostic gap from non-contrast CT (NCCT)-Alberta Stroke Program Early Computed Tomography Score (ASPECTS) in hyperacute stroke and may help to explain futile recanalization
We defined three subgroups based on onset-time to imaging (OTI): a) hyperacute stroke with OTI < 100 min (55 patients, 40%); b) imaging between 100 and 200 min (45 patients, 33%) and c) imaging ≥ 200 min after symptom onset (36 patients, 27%)
Summary
Mechanical thrombectomy (MT) is a successful and effective treatment in acute ischemic stroke due to large vesselocclusion [1, 2]. While treatment decision in extended time from symptom onset to treatment (OTT) relies on defined mismatch criteria [3, 4], patient selection in OTT ≤ 6 h relies typically on the extent of early signs of infarction on non-contrast CT (NCCT) [5]. In hyperacute stroke, ischemic changes on acute NCCT can be very subtle [7,8,9]. Reduced interrater-reliability was observed for ASPECTS within an onset-time to imaging (OTI) ≤ 100 min [10]. In patients treated with intravenous alteplase, a significant timeto-CT interaction regarding interrater-reliability and prognostic accuracy of ASPECTS has been reported before [11]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
