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Background and Purpose-On top of functional outcome, accurate prediction of cognitive outcome for stroke patients is an unmet need with major implications for clinical management. We investigated whether stroke location may contribute independent prognostic value to multifactorial predictive models of functional and cognitive outcomes. Methods-Four hundred twenty-eight consecutive patients with ischemic stroke were prospectively assessed with magnetic resonance imaging at 24 to 72 hours and at 3 months for functional outcome using the modified Rankin Scale and cognitive outcome using the Montreal Cognitive Assessment (MoCA). Statistical maps of functional and cognitive eloquent regions were derived from the first 215 patients (development sample) using voxel-based lesion-symptom mapping. We used multivariate logistic regression models to study the influence of stroke location (number of eloquent voxels from voxel-based lesion-symptom mapping maps), age, initial National Institutes of Health Stroke Scale and stroke volume on modified Rankin Scale and MoCA. The second part of our cohort was used as an independent replication sample. Results-In univariate analyses, stroke location, age, initial National Institutes of Health Stroke Scale, and stroke volume were all predictive of poor modified Rankin Scale and MoCA. In multivariable analyses, stroke location remained the strongest independent predictor of MoCA and significantly improved the prediction compared with using only age, initial National Institutes of Health Stroke Scale, and stroke volume (area under the curve increased from 0.697-0.771; difference=0.073; 95% confidence interval, 0.008-0.155). In contrast, stroke location did not persist as independent predictor of modified Rankin Scale that was mainly driven by initial National Institutes of Health Stroke Scale (area under the curve going from 0.840 to 0.835). Similar results were obtained in the replication sample. Conclusions-Stroke location is an independent predictor of cognitive outcome (MoCA) at 3 months post stroke.

Background and Purpose: The efficiency of prehospital care chain response and the adequacy of hospital resources are challenged amid the coronavirus disease 2019 (COVID-19) outbreak, with suspected consequences for patients with ischemic stroke eligible for mechanical thrombectomy (MT). Methods: We conducted a prospective national-level data collection of patients treated with MT, ranging 45 days across epidemic containment measures instatement, and of patients treated during the same calendar period in 2019. The primary end point was the variation of patients receiving MT during the epidemic period. Secondary end points included care delays between onset, imaging, and groin puncture. To analyze the primary end point, we used a Poisson regression model. We then analyzed the correlation between the number of MTs and the number of COVID-19 cases hospitalizations, using the Pearson correlation coefficient (compared with the null value). Results: A total of 1513 patients were included at 32 centers, in all French administrative regions. There was a 21% significant decrease (0.79; [95%CI, 0.76–0.82]; P <0.001) in MT case volumes during the epidemic period, and a significant increase in delays between imaging and groin puncture, overall (mean 144.9±SD 86.8 minutes versus 126.2±70.9; P <0.001 in 2019) and in transferred patients (mean 182.6±SD 82.0 minutes versus 153.25±67; P <0.001). After the instatement of strict epidemic mitigation measures, there was a significant negative correlation between the number of hospitalizations for COVID and the number of MT cases ( R 2 −0.51; P =0.04). Patients treated during the COVID outbreak were less likely to receive intravenous thrombolysis and to have unwitnessed strokes (both P <0.05). Conclusions: Our study showed a significant decrease in patients treated with MTs during the first stages of the COVID epidemic in France and alarming indicators of lengthened care delays. These findings prompt immediate consideration of local and regional stroke networks preparedness in the varying contexts of COVID-19 pandemic evolution.

See Duering and Schmidt (doi:10.1093/awx135) for a scientific commentary on this article.Thalamic alterations have been observed in infarcts initially sparing the thalamus but interrupting thalamo-cortical or cortico-thalamic projections. We aimed at extending this knowledge by demonstrating with in vivo imaging sensitive to iron accumulation, one marker of neurodegeneration, that (i) secondary thalamic alterations are focally located in specific thalamic nuclei depending on the initial infarct location; and (ii) such secondary alterations can contribute independently to the long-term outcome. To tackle this issue, 172 patients with an infarct initially sparing the thalamus were prospectively evaluated clinically and with magnetic resonance imaging to quantify iron through R2* map at 24-72 h and at 1-year follow-up. An asymmetry index was used to compare R2* within the thalamus ipsilateral versus contralateral to infarct and we focused on the 95th percentile of R2* as a metric of high iron content. Spatial distribution within the thalamus was analysed on an average R2* map from the entire cohort. The asymmetry index of the 95th percentile within individual nuclei (medio-dorsal, pulvinar, lateral group) were compared according to the initial infarct location in simple and multiple regression analyses and using voxel-based lesion-symptom mapping. Associations between the asymmetry index of the 95th percentile and functional, cognitive and emotional outcome were calculated in multiple regression models. We showed that R2* was not modified at 24-72 h but showed heterogeneous increase at 1 year mainly within the medio-dorsal and pulvinar nuclei. The asymmetry index of the 95th percentile within the medio-dorsal nucleus was significantly associated with infarcts involving anterior areas (frontal P = 0.05, temporal P = 0.02, lenticular P = 0.01) while the asymmetry index of the 95th percentile within the pulvinar nucleus was significantly associated with infarcts involving posterior areas (parietal P = 0.046, temporal P < 0.001) independently of age, gender and infarct volume, which was confirmed by voxel-based lesion-symptom mapping. The asymmetry index of the 95th percentile within the entire thalamus at 1 year was independently associated with poor functional outcome (P = 0.04), poor cognitive outcome (P = 0.03), post-stroke anxiety (P = 0.04) and post-stroke depression (P = 0.02). We have therefore identified that iron accumulates within the thalamus ipsilateral to infarct after a delay with a focal distribution that is strongly linked to the initial infarct location (in relation with the pattern of connectivity between thalamic nuclei and cortical areas or deep nuclei), which independently contributes to functional, cognitive and emotional outcome.

≈70% of their initial motor impairment, 4,5 which, therefore, already conveys strong predictive information. Nevertheless, this 70% rule fails in patients with initial severe deficit, 4,5 and the variability in medium to long-term outcome is not adequately explained by initial clinical severity alone for those patients. The interindividual variability in the relation between initial impairment and subsequent recovery hampers accurate individualized prognosis. 6 Although infarct volume could be helpful to improve prognostication, 7 its power as an independent predictor of clinical outcome is still debated. 8Background and Purpose-The contribution of imaging metrics to predict poststroke motor recovery needs to be clarified.We tested the added value of early diffusion tensor imaging (DTI) of the corticospinal tract toward predicting long-term motor recovery. Methods-One hundred seventeen patients were prospectively assessed at 24 to 72 hours and 1 year after ischemic stroke with diffusion tensor imaging and motor scores (Fugl-Meyer). The initial fiber number ratio (iFNr) and final fiber number ratio were computed as the number of streamlines along the affected corticospinal tract normalized to the unaffected side and were compared with each other. The prediction of motor recovery (ΔFugl-Meyer) was first modeled using initial Fugl-Meyer and iFNr. Multivariate ordinal logistic regression models were also used to study the association of iFNr, initial Fugl-Meyer, age, and stroke volume with Fugl-Meyer at 1 year. Results-The iFNr correlated with the final fiber number ratio at 1 year (r=0.70; P<0.0001). The initial Fugl-Meyer strongly predicted motor recovery (≈73% of initial impairment) for all patients except those with initial severe stroke (FuglMeyer<50). For these severe patients (n=26), initial Fugl-Meyer was not correlated with motor recovery (R 2 =0.13; p=ns), whereas iFNr showed strong correlation (R 2 =0.56; P<0.0001). In multivariate analysis, the iFNr was an independent predictor of motor outcome (β=2.601; 95% confidence interval=0.304-5.110; P=0.031), improving prediction compared with using only initial Fugl-Meyer, age, and stroke volume (P=0.026). Conclusions-Early measurement of FNr at 24 to 72 hours poststroke is a surrogate marker of corticospinal tract integrity and provides independent prediction of motor outcome at 1 year especially for patients with severe initial impairment.

Background and Purpose: Acute ischemic stroke and large vessel occlusion can be concurrent with the coronavirus disease 2019 (COVID-19) infection. Outcomes after mechanical thrombectomy (MT) for large vessel occlusion in patients with COVID-19 are substantially unknown. Our aim was to study early outcomes after MT in patients with COVID-19. Methods: Multicenter, European, cohort study involving 34 stroke centers in France, Italy, Spain, and Belgium. Data were collected between March 1, 2020 and May 5, 2020. Consecutive laboratory-confirmed COVID-19 cases with large vessel occlusion, who were treated with MT, were included. Primary investigated outcome: 30-day mortality. Secondary outcomes: early neurological improvement (National Institutes of Health Stroke Scale improvement ≥8 points or 24 hours National Institutes of Health Stroke Scale 0–1), successful reperfusion (modified Thrombolysis in Cerebral Infarction grade ≥2b), and symptomatic intracranial hemorrhage. Results: We evaluated 93 patients with COVID-19 with large vessel occlusion who underwent MT (median age, 71 years [interquartile range, 59–79]; 63 men [67.7%]). Median pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early Computed Tomography score were 17 (interquartile range, 11–21) and 8 (interquartile range, 7–9), respectively. Anterior circulation acute ischemic stroke represented 93.5% of cases. The rate modified Thrombolysis in Cerebral Infarction 2b to 3 was 79.6% (74 patients [95% CI, 71.3–87.8]). Thirty-day mortality was 29% (27 patients [95% CI, 20–39.4]). Early neurological improvement was 19.5% (17 patients [95% CI, 11.8–29.5]), and symptomatic intracranial hemorrhage was 5.4% (5 patients [95% CI, 1.7–12.1]). Patients who died at 30 days exhibited significantly lower lymphocyte count, higher levels of aspartate, and LDH (lactate dehydrogenase). After adjustment for age, initial National Institutes of Health Stroke Scale, Alberta Stroke Program Early Computed Tomography score, and successful reperfusion, these biological markers remained associated with increased odds of 30-day mortality (adjusted odds ratio of 2.70 [95% CI, 1.21–5.98] per SD-log decrease in lymphocyte count, 2.66 [95% CI, 1.22–5.77] per SD-log increase in aspartate, and 4.30 [95% CI, 1.43–12.91] per SD-log increase in LDH). Conclusions: The 29% rate of 30-day mortality after MT among patients with COVID-19 is not negligible. Abnormalities of lymphocyte count, LDH and aspartate may depict a patient’s profiles with poorer outcomes after MT. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04406090.

Objective. To evaluate the relationship between normal appearing white matter (NAWM) integrity and post-ischemic stroke recovery in four main domains including, cognition, mood, gait, and dependency. Methods. A prospective study was conducted, including patients diagnosed for an ischemic supratentorial stroke on a 3T-brain MRI performed 24-72 hours after symptoms onset. Clinical assessment one-year after stroke included a Montreal Cognitive Assessment, an Isaacs set test (IST), a Zazzo's cancellation task, a Hospital anxiety and depression scale, a 10-m walking test, a modified Rankin scale (mRS). DTI parameters in the NAWM were computed using FMRIB's Diffusion Toolbox. The relationships between mean NAWM DTI parameters and the clinical scores were assessed using linear and ordinal regression analyses, including the volumes of white matter hyperintensities (WMH), grey matter and ischemic stroke as radiological covariates. Results. 207 subjects were included (66 ± 13 y.o, 67% men, median NIHSS 3, interquartile range 2-6). In the models including only radiological variables, NAWM fractional anisotropy (FA) was associated with the mRS and the cognitive scores. After adjusting for demographic confounders, NAWM FA remained a significant predictor of mRS (β =-0.24, p = 0.04). Additional path analysis showed that NAWM FA had a direct effect on mRS (β =-0.241, p = 0.001), and a less important indirect effect mediating WMH burden. Similar results were found with mean diffusivity, axial and radial diffusivity. In further subgroup analyses, a relationship between NAWM integrity in widespread white matter tracts, mRS and IST was found in right-hemispheric strokes. Conclusion. NAWM DTI parameters measured early after an ischemic stroke are independent predictors of functional outcome and may be additional markers to include in studies evaluating poststroke recovery.

Background and Purpose— Nonagenarians represent a growing stroke population characterized by a higher frailty. Although endovascular therapy (ET) is a cornerstone of the management of acute ischemic stroke related to large vessel occlusion, the benefit of reperfusion among nonagenarians is poorly documented. We aimed to assess the impact of ET-related reperfusion on the functional outcome of reperfusion in this elderly population. Methods— A retrospective analysis of clinical and imaging data from all patients aged over 90 included in the ETIS (Endovascular Treatment in Ischemic Stroke) registry between October 2013 and April 2018 was performed. Association between post-ET reperfusion and favorable (modified Rankin Scale [0–2] or equal to prestroke value) and good (modified Rankin Scale [0–3] or equal to prestroke value) outcome were evaluated. Demographic and procedural predictors of functional outcome, including the first-pass effect, were evaluated. Results were adjusted for center, admission National Institutes of Health Stroke Scale, and use of intravenous thrombolysis. Results— Among the 124 nonagenarians treated with ET, those with successful reperfusion had the lowest 90-day modified Rankin Scale (odds ratio, 3.26; 95% CI, 1.04–10.25). Only patients with successful reperfusion after the first pass (n=53, 56.7%) had a reduced 90-day mortality (odds ratio, 0.15; 95% CI, 0.05–0.45) and an increased rate of good outcome (odds ratio, 4.55; 95% CI, 1.38–15.03). No increase in the rate of intracranial hemorrhage was observed among patients successfully reperfused. Conclusions— Successful reperfusion improves the functional outcome of nonagenarians who should not be excluded from ET. The first-pass effect should be considered in the procedural management of this frail population.