Physiological evidence suggests that neighboring brain regions have similar perfusion characteristics (vascular supply, collateral blood flow). It is largely unknown whether integrating perfusion CT ...(pCT) information from the area surrounding a given voxel (i.e. the receptive field (RF)) improves the prediction of infarction of this voxel. Based on general linear regression models (GLMs) and using acute pCT-derived maps, we compared the added value of cuboid RF to predict the final infarct. To this aim, we included 144 stroke patients with acute pCT and follow-up MRI, used to delineate the final infarct. Overall, the performance of GLMs to predict the final infarct improved when using RF for all pCT maps (cerebral blood flow, cerebral blood volume, mean transit time and time-to-maximum of the tissue residual function (Tmax)). The highest performance was obtained with Tmax (glm(Tmax); AUC = 0.89 ± 0.03 with RF vs. 0.78 ± 0.02 without RF; p < 0.001) and with a model combining all perfusion parameters (glm(multi); AUC 0.89 ± 0.02 with RF vs. 0.79 ± 0.02 without RF; p < 0.001). These results suggest that prediction of infarction improves by integrating perfusion information from adjacent tissue. This approach may be applied in future studies to better identify ischemic core and penumbra thresholds and improve patient selection for acute stroke treatment.
The COVID-19 pandemic has considerably altered the regular medical education curriculum while increasing the need for health care professionals. Senior medical students are being incrementally ...deployed to the front line to address the shortage of certified physicians. These students, some of whom will be fast-tracked as physicians, may lack knowledge regarding the initial management of time-critical emergencies such as stroke.
Our aim was to determine whether an e-learning module could improve asynchronous distance knowledge acquisition of the National Institutes of Health Stroke Scale (NIHSS) in senior medical students compared to the traditional didactic video.
A randomized, data analyst-blinded web-based trial was conducted at the University of Geneva Faculty of Medicine between April and June 2020. Fifth year medical students followed a distance learning path designed to teach the NIHSS. The control group followed the traditional didactic video created by Patrick Lyden, while the e-learning group followed the updated version of a previously tested, highly interactive e-learning module. The main outcome was the score on a 50-question quiz displayed upon completion of the learning material. The difference in the proportion of correct answers for each specific NIHSS item was also assessed.
Out of 158 potential participants, 88 started their allocated learning path and 75 completed the trial. Participants who followed the e-learning module performed better than those who followed the video (38 correct answers, 95% CI 37-39, vs 35 correct answers, 95% CI 34-36, P<.001). Participants in the e-learning group scored better on five elements than the video group: key NIHSS concepts (P=.02), the consciousness - global item (P<.001), the facial palsy item (P=.04), the ataxia item (P=.03), and the sensory item (P=.04).
Compared to the traditional didactic video, a highly interactive e-learning module enhances asynchronous distance learning and NIHSS knowledge acquisition in senior medical students.
IMPORTANCE: The best reperfusion strategy in patients with acute minor stroke and large vessel occlusion (LVO) is unknown. Accurately predicting early neurological deterioration of presumed ischemic ...origin (ENDi) following intravenous thrombolysis (IVT) in this population may help to select candidates for immediate transfer for additional thrombectomy. OBJECTIVE: To develop and validate an easily applicable predictive score of ENDi following IVT in patients with minor stroke and LVO. DESIGN, SETTING, AND PARTICIPANTS: This multicentric retrospective cohort included 729 consecutive patients with minor stroke (National Institutes of Health Stroke Scale NIHSS score of 5 or less) and LVO (basilar artery, internal carotid artery, first M1 or second M2 segment of middle cerebral artery) intended for IVT alone in 45 French stroke centers, ie, including those who eventually received rescue thrombectomy because of ENDi. For external validation, another cohort of 347 patients with similar inclusion criteria was collected from 9 additional centers. Data were collected from January 2018 to September 2019. MAIN OUTCOMES AND MEASURES: ENDi, defined as 4 or more points’ deterioration on NIHSS score within the first 24 hours without parenchymal hemorrhage on follow-up imaging or another identified cause. RESULTS: Of the 729 patients in the derivation cohort, 335 (46.0%) were male, and the mean (SD) age was 70 (15) years; of the 347 patients in the validation cohort, 190 (54.8%) were male, and the mean (SD) age was 69 (15) years. In the derivation cohort, the median (interquartile range) NIHSS score was 3 (1-4), and the occlusion site was the internal carotid artery in 97 patients (13.3%), M1 in 207 (28.4%), M2 in 395 (54.2%), and basilar artery in 30 (4.1%). ENDi occurred in 88 patients (12.1%; 95% CI, 9.7-14.4) and was strongly associated with poorer 3-month outcomes, even in patients who underwent rescue thrombectomy. In multivariable analysis, a more proximal occlusion site and a longer thrombus were independently associated with ENDi. A 4-point score derived from these variables—1 point for thrombus length and 3 points for occlusion site—showed good discriminative power for ENDi (C statistic = 0.76; 95% CI, 0.70-0.82) and was successfully validated in the validation cohort (ENDi rate, 11.0% 38 of 347; C statistic = 0.78; 95% CI, 0.70-0.86). In both cohorts, ENDi probability was approximately 3%, 7%, 20%, and 35% for scores of 0, 1, 2 and 3 to 4, respectively. CONCLUSIONS AND RELEVANCE: The substantial ENDi rates observed in these cohorts highlights the current debate regarding whether to directly transfer patients with IVT-treated minor stroke and LVO for additional thrombectomy. Based on the strong associations observed, an easily applicable score for ENDi risk prediction that may assist decision-making was derived and externally validated.
Whether endovascular therapy (EVT) added on best medical management (BMM), as compared to BMM alone, is beneficial in acute ischemic stroke with isolated posterior cerebral artery occlusion is ...unknown.
We conducted a multicenter international observational study of consecutive stroke patients admitted within 6 hours from symptoms onset in 26 stroke centers with isolated occlusion of the first (P1) or second (P2) segment of the posterior cerebral artery and treated either with BMM+EVT or BMM alone. Propensity score with inverse probability of treatment weighting was used to account for baseline between-groups differences. The primary outcome was 3-month good functional outcome (modified Rankin Scale mRS score 0-2 or return to baseline modified Rankin Scale). Secondary outcomes were 3-month excellent recovery (modified Rankin Scale score 0-1), symptomatic intracranial hemorrhage, and early neurological deterioration.
Overall, 752 patients were included (167 and 585 patients in the BMM+EVT and BMM alone groups, respectively). Median age was 74 (interquartile range, 63-82) years, 329 (44%) patients were female, median National Institutes of Health Stroke Scale was 6 (interquartile range 4-10), and occlusion site was P1 in 188 (25%) and P2 in 564 (75%) patients. Baseline clinical and radiological data were similar between the 2 groups following propensity score weighting. EVT was associated with a trend towards lower odds of good functional outcome (odds ratio, 0.81 95% CI, 0.66-1.01;
=0.06) and was not associated with excellent functional outcome (odds ratio, 1.17 95% CI, 0.95-1.43;
=0.15). EVT was associated with a higher risk of symptomatic intracranial hemorrhage (odds ratio, 2.51 95% CI, 1.35-4.67;
=0.004) and early neurological deterioration (odds ratio, 2.51 95% CI, 1.64-3.84;
<0.0001).
In this observational study of patients with proximal posterior cerebral artery occlusion, EVT was not associated with good or excellent functional outcome as compared to BMM alone. However, EVT was associated with higher rates of symptomatic intracranial hemorrhage and early neurological deterioration. EVT should not be routinely recommended in this population, but randomization into a clinical trial is highly warranted.
OBJECTIVETo compare outcomes after endovascular therapy (EVT) and IV thrombolysis (IVT) in patients with stroke with emergent large vessel occlusion (LVO) and mild neurologic deficits.
METHODSThis ...was a retrospective analysis of patients from the Swiss Stroke Registry with admission NIH Stroke Scale score ≤5 and LVO treated by EVT (± IVT) vs IVT alone. The primary endpoint was favorable functional outcome (modified Rankin Scale mRS score 0–1) at 3 months. Secondary outcomes were independence (mRS score 0–2), mRS score (ordinal shift analysis), and survival with high disability (mRS score 4–5). Safety endpoints were mortality and symptomatic hemorrhage.
RESULTSOf 11,356 patients, 312 met the criteria and propensity score method matched 108 in each group. A comparably large proportion of patients with EVT and IVT had favorable outcome (63% vs 65.7% respectively; odds ratio 0.94, 95% confidence interval 0.51–1.72; p = 0.840). Patients with EVT showed a nonsignificant trend toward higher mRS score at 3 months (p = 0.717), while the proportion of surviving patients with high disability was comparably very low in both groups (p = 0.419). Mortality was slightly higher among those with EVT (9.3% vs 2.8%; p = 0.06), and symptomatic intracranial hemorrhage was a rare event in both groups (2.8% vs 0%; p = 0.997).
CONCLUSIONSIn acute ischemic stroke, EVT and IVT appear similarly effective in achieving favorable outcome at 3 months for patients with LVO and mild neurologic symptoms. EVT might be marginally inferior to IVT regarding outcome across all levels of disability and mortality. Further studies are required to determine whether certain subgroups of patients with LVO and mild symptoms benefit from EVT.
CLASSIFICATION OF EVIDENCEThis study provides Class III evidence that patients with LVO and mild symptoms receiving either EVT or IVT had similar favorable functional outcomes at 3 months.
Abstract
Background
The relative frequency of ischaemic versus haemorrhagic stroke among patients with chronic kidney disease (CKD) has not been clearly described. Moreover, no recent meta-analysis ...has investigated the outcomes of patients with CKD treated with thrombolysis for acute ischaemic stroke. We conducted a systematic review and meta-analysis to estimate the proportion of stroke subtypes and the outcomes of thrombolysis in CKD.
Methods
A PubMed, EMBASE and Cochrane literature research was conducted. The primary outcome was the proportion and incidence of ischaemic versus haemorrhagic strokes among patients with CKD. In addition, we assessed the impact of CKD on disability, mortality and bleeding among patients with acute ischaemic stroke treated with thrombolysis. The pooled proportion and the risk ratio were estimated using a random-effects model.
Results
Thirty-nine observational studies were included: 22 on the epidemiology of stroke types and 17 on the outcomes of thrombolysis in this population. In the main analysis (>99 281 patients), ischaemic stroke was more frequent than haemorrhagic among patients with CKD 78.3%, 95% confidence interval (CI) 73.3–82.5%. However, among patients with kidney failure, the proportion of ischaemic stroke decreased and was closer to that of haemorrhagic stroke (59.8%, 95% CI 49.4–69.4%). CKD was associated with worse clinical outcomes in patients with acute ischaemic stroke compared with patients with preserved kidney function.
Conclusions
The relative frequency of haemorrhagic stroke seems to increase as kidney function declines. Among patients with acute ischaemic stroke treated with thrombolysis, presence of CKD is associated with higher disability, mortality and bleeding, compared with patients with preserved kidney function.
Posterior thalamic pulvinar nuclei have been implicated in different aspects of spatial attention, but their exact role in humans remain unclear. Most neuropsychological studies of attention deficits ...after pulvinar lesion have concerned single patients or small samples. Here we examined a group of 13 patients with focal damage to posterior thalamus on a visual search task with faces, allowing us to test several hypotheses concerning pulvinar function in controlling attention to visually salient or emotionally significant stimuli. Our results identified two subgroups of thalamic patients with distinct patterns of attentional responsiveness to emotional and colour features in face targets. One group with lesions located in anterior and ventral portions of thalamus showed intact performance, with a normal facilitation of visual search for faces with emotional (fearful or happy) expressions on both side of space, similar to healthy controls. By contrast, a second group showed a slower and poorer detection of face targets, most severe for neutral faces, but with a paradoxically enhanced facilitation by both colour and emotional features. This second group had lesions centred on the pulvinar, involving mainly the dorso-medial sectors in patients showing enhanced effects of colour features, but extending to more dorso-lateral sectors in those with enhanced effects of emotional features. These findings reveal that pulvinar nuclei are not critical for orienting attention to emotionally or visually salient features, but instead provide new evidence in support of previous hypotheses suggesting an important role in controlling attention in visual scenes with distracting information.
Introduction In western countries, stroke is the fourth leading cause of death, after heart disease, cancer and chronic respiratory diseases. 1 Carotid artery disease may be responsible for 10-15% of ...all ischaemic strokes. 2 Randomised controlled trials (RCTs) have established the benefit of carotid endarterectomy (CEA) over medical management in patients with carotid disease. 3 Recent studies suggest that medical treatment including dual antiplatelet therapy and high-dose statins may result in lower incidence of recurrent events in symptomatic patients awaiting carotid revascularisation. 4 In asymptomatic patients with carotid stenosis greater than 60% the overall estimated risk of stroke may be 1-2% per year, although this may increase due to older age, multilevel vascular disease or smoking. 5 At the other end of the spectrum, with best medical treatment in selected patients with moderate (>=50%) asymptomatic carotid stenosis the annual incidence of stroke may be as low as 0.5%.
PDF
