| Objective:The effect of imaging selection paradigms on endovascular thrombectomy outcomes in acute ischemic stroke patients with large vessel occlusion remains uncertain.The study aimed to assess the effect of basic imaging(noncontrast computed tomography(NCCT)with or without computed tomographic angiography(CTA))versus advanced imaging(magnetic resonance imaging(MRI)or computed tomography perfusion(CTP))on clinical outcomes following thrombectomy in stroke patients with large vessel occlusion(LVO)in the early and extended windows using a pooled analysis of patient-level data from two pivotal randomized clinical trials done in China.Methods: This post-hoc analysis used data from 1182 patients included in two multicenter,randomized controlled trials in China that evaluated adjunct therapies to endovascular treatment for acute ischemic stroke(Direct Endovascular Treatment for Large Artery Anterior Circulation Stroke performed from May 20,2018,through May 2,2020,and Intravenous Tirofiban Before Endovascular Treatment in Stroke from October10,2018,through October 31,2021).Patients from two randomized controlled trials with occlusion of the intracranial internal carotid artery or proximal middle cerebral artery(M1/M2 segments)were categorized according to baseline imaging modality(basic versus advanced)as well as treatment time window(early: 0-6 hours versus extended:6-24 hours from last known well to puncture).The primary outcome was the proportion of patients with functional independence(modified Rankin scale score of 0-2)at 90 days.Secondary outcomes included the percentage of 90-day excellent outcome(m RS score 0to 1),the distribution of the m RS score at 90 days.The safety outcomes included mortality within 90 days,symptomatic intracranial hemorrhage(s ICH)within 48 hours.The Poisson regression was performed to assess the association of imaging selection modality with functional independence and other binary outcomes.The ordinal logistic regression was used to estimate the shift towards 1-ponit improvement of m RS scores at90 days.Result:1.A total of 1182 patients were included in this cohort analysis,with 648 in the early(471 with basic imaging versus 177 advanced imaging)and 534 in the extended(222 basic imaging versus 312 advanced imaging)time window.In the early window,the median(interquartile range)age,baseline ASPECTS score,and baseline NIHSS score for the cohort were 70(60-76)years,8(6-9),and 16(13-20),respectively.In the extended window,the median(interquartile range)age,baseline ASPECTS score,and baseline NIHSS score for the cohort were 66(56-74)years,7(6-9),and 15(11-19),respectively.2.In the early window,227(48.2%)patients with basic and 91(51.4%)patients with advanced imaging achieved functional independence at 90 days.In the extended window,102(45.9%)patients with basic and 145(46.5%)patients with advanced imaging achieved functional independence at 90 days.After adjusting for confounders,we did not detect significant differences in functional independence between the two groups both in the early(adjusted RR,0.99(95% CI,0.84-1.16);P=0.91)and extended windows(adjusted RR,1.00(95% CI,0.84-1.20);P=0.97).There were no differences in functional disability(m RS shift)or excellent outcomes across the two groups in either time window.3.In the early window,patients with basic imaging had higher rates of mortality within 90 days than patients with advanced imaging(20.0% vs 12.4%,P=0.03).However,this difference was not significant after adjusting for confounding factors(adjusted RR,1.45(95% CI,0.95-2.20),P=0.09).There was also no difference in mortality between the2 groups in the extended window(adjusted RR,1.07;95% CI,0.74-1.54;P=0.73).The rates of s ICH were similar between the two groups both in the early and extended windows.Conclusion: For patients with acute ischemic stroke due to anterior circulation within 24 hours of symptom onset,there was no relationship between the utilization of advanced imaging and 90-day functional independence.There was no significant difference in the incidence of symptomatic intracerebral hemorrhage and mortality between the two imaging selection modalities.Basic imaging modality(NCCT±CTA)alone can be a reasonable alternative selection strategy to advanced imaging modality(MRI or CTP).NCCT as an easier and more widespread basic imaging modality could optimize the clinical lifesaving process and expand the patients who could benefit from EVT potentially.These findings need to be applied with caution and need to be further validated in prospective randomized controlled clinical trials. |
