Noncontrasted head computed tomography (NCHCT) has long been the standard of care for acute stroke imaging. New guidelines recommending advanced vascular imaging to identify eligible patients for ...endovascular therapy have renewed safety concerns on the use of contrast in the emergent setting without laboratory confirmation of renal function.
We compared computed tomographic angiography (CTA) versus NCHCT alone during acute stroke evaluation with focus on renal safety and timeliness of therapy delivery. We reviewed data on all emergency department patients for whom the Acute Stroke Intervention Team was activated between December 2013 and September 2014. Primary outcomes included acute kidney injury and change in serum creatinine from presentation to 24 to 48 hours (Δ serum creatinine Cr). We assessed therapy delay using door-to-CT and door-to-needle times.
Of 289 patients requiring Acute Stroke Intervention Team activation, 157 received CTA and 132 NCHCT only. There was no difference between groups in mean Cr at 24 to 48 hours (1.06 CTA; 1.40 NCHCT; P=0.059), ΔCr (-0.07 CTA, -0.11 NCHCT, P=0.489), or rates of acute kidney injury (5 CTA, 7 NCHCT, P=0.422). There was no significant difference in mean intravenous tissue plasminogen activator treatment times (68.11 minutes CTA, 81.36 minutes NCHCT; P=0.577). In the 157 patients who underwent CTA, 16 (10.2%) vascular anomalies and 55 (35.0%) high-grade stenoses or occlusions were identified.
CTA acquisition during acute stroke evaluation was safe with regards to renal function and did not delay appropriate therapy delivery. Acute CTA acquisition offers additional clinical value in rapid identification of vascular abnormalities.
The standard neurology clinical experience in medical school focuses primarily on bedside patient encounters; however, the limitations of the clinical environment due to the current COVID-19 pandemic ...have accelerated the need for virtual curriculum development. To provide guidance to Neurology clerkship directors during this unprecedented time, the American Academy of Neurology (AAN) Undergraduate Education Subcommittee (UES) formed a workgroup to develop an outline for a virtual curriculum, provide recommendations, and describe models of integrating virtual curricula into the neurology clerkship. In this overview, we discuss different methods of virtual instruction, hybrid models of clerkship training and the challenges to its implementation, professionalism issues, and modification of feedback and assessment techniques specific to the virtual learning environment. We also offer suggestions for implementation of a hybrid virtual curriculum into the neurology clerkship. The virtual curriculum is intended to supplement the core neurology in-person clinical experience and should not be used for shortening or replacing the required neurology clinical clerkship.
Background
Current EMS stroke screening tools facilitate early detection and triage, but the tools' accuracy and reliability are limited and highly variable. An automated stroke screening tool could ...improve stroke outcomes by facilitating more accurate prehospital diagnosis and delivery. We hypothesize that a machine learning algorithm using video analysis can detect common signs of stroke. As a proof-of-concept study, we trained a computer algorithm to detect presence and laterality of facial weakness in publically available videos with comparable accuracy, sensitivity, and specificity to paramedics.
Methods and Results
We curated videos of people with unilateral facial weakness (
n
= 93) and with a normal smile (
n
= 96) from publicly available web-based sources. Three board certified vascular neurologists categorized the videos according to the presence or absence of weakness and laterality. Three paramedics independently analyzed each video with a mean accuracy, sensitivity and specificity of 92.6% 95% CI 90.1–94.7%, 87.8% 95% CI 83.9–91.7% and 99.3% 95% CI 98.2–100%. Using a 5-fold cross validation scheme, we trained a computer vision algorithm to analyze the same videos producing an accuracy, sensitivity and specificity of 88.9% 95% CI 83.5–93%, 90.3% 95% CI 82.4–95.5% and 87.5 95% CI 79.2–93.4%.
Conclusions
These preliminary results suggest that a machine learning algorithm using computer vision analysis can detect unilateral facial weakness in pre-recorded videos with an accuracy and sensitivity comparable to trained paramedics. Further research is warranted to pursue the concept of augmented facial weakness detection and external validation of this algorithm in independent data sets and prospective patient encounters.
Evidence of the so-called "obesity paradox," which refers to the protective effect and survival benefit of obesity in patients with spontaneous intracerebral hemorrhage (ICH), remains controversial. ...This study aims to determine the association between body mass index (BMI) and functional outcomes in patients with ICH and whether it is modified by race/ethnicity.
Included individuals were derived from the Ethnic/Racial Variations of Intracerebral Hemorrhage study, which prospectively recruited 1,000 non-Hispanic White, 1,000 non-Hispanic Black, and 1,000 Hispanic patients with spontaneous ICH. Only patients with available BMI were included. The primary outcome was 90-day mortality. Secondary outcomes were mortality at discharge, modified Rankin Scale (mRS), Barthel Index, and self-reported health status measures at 90 days. Associations between BMI and ICH outcomes were assessed using univariable and multivariable logistic, ordinal, and linear regression models, as appropriate. Sensitivity analyses after excluding frail patients and by patient race/ethnicity were performed.
A total of 2,841 patients with ICH were included. The median age was 60 years (interquartile range 51-73). Most patients were overweight (n = 943; 33.2%) or obese (n = 1,032; 36.3%). After adjusting for covariates, 90-day mortality was significantly lower among overweight and obese patients than their normal weight counterparts (adjusted odds ratio aOR = 0.71 0.52-0.98 and aOR = 0.70 0.50-0.97, respectively). Compared with patients with BMI <25 kg/m
, those with BMI ≥25 kg/m
had better 90-day mRS (aOR = 0.80 CI 0.67-0.95), EuroQoL Group 5-Dimension (EQ-5D) (aβ = 0.05 0.01-0.08), and EQ-5D VAS (aβ = 3.80 0.80-6.98) scores. These differences persisted after excluding withdrawal of care patients. There was an inverse relationship between BMI and 90-day mortality (aOR = 0.97 0.96-0.99). Although non-Hispanic White patients had significantly higher 90-day mortality than non-Hispanic Black and Hispanic (26.6% vs 19.5% vs 18.0%, respectively;
< 0.001), no significant interactions were found between BMI and race/ethnicity. No significant interactions between BMI and age or sex for 90-day mortality were found, whereas for 90-day mRS, there was a significant interaction with age (
= 0.004).
We demonstrated that a higher BMI is associated with decreased mortality, improved functional outcomes, and better self-reported health status at 90 days, thus supporting the paradoxical role of obesity in patients with ICH. The beneficial effect of high BMI does not seem to be modified by race/ethnicity or sex, whereas age may play a significant role in patient functional outcomes.
To assess the impact of dissected artery occlusion (DAO) on functional outcome and complications in patients with cervical artery dissection (CeAD).
We analyzed combined individual patient data from ...3 multicenter cohorts of consecutive patients with CeAD (the Cervical Artery Dissection and Ischemic Stroke Patients CADISP-Plus consortium dataset). Patients with data on DAO and functional outcome were included. We compared patients with DAO to those without DAO. Primary outcome was favorable functional outcome (i.e., modified Rankin Scale mRS score 0-1) measured 3-6 months from baseline. Secondary outcomes included delayed cerebral ischemia, major hemorrhage, recurrent CeAD, and death. We performed univariate and multivariable binary logistic regression analyses and calculated odds ratios (OR) with 95% confidence intervals (CI), with adjustment for potential confounders.
Of 2,148 patients (median age 45 years interquartile range (IQR) 38-52, 43.6% women), 728 (33.9%) had DAO. Patients with DAO more frequently presented with cerebral ischemia (84.6% vs 58.5%,
< 0.001). Patients with DAO were less likely to have favorable outcome when compared to patients without DAO (mRS 0-1: 59.6% vs 80.1%,
< 0.001). After adjustment for age, sex, and initial stroke severity, DAO was independently associated with less favorable outcome (mRS 0-1: OR 0.65, CI 0.50-0.84,
= 0.001). Delayed cerebral ischemia occurred more frequently in patients with DAO than in patients without DAO (4.5% vs 2.9%,
= 0.059).
DAO independently predicts less favorable functional outcome in patients with CeAD. Further research on vessel patency, collateral status and effects of revascularization therapies particularly in patients with DAO is warranted.
Mixed data exist regarding the association between hyperglycemia and functional outcome after acute ischemic stroke when accounting for the impact of leptomeningeal collateral flow. We sought to ...determine whether collateral status modifies the association between treatment group and functional outcome in a subset of patients with large vessel occlusion enrolled in the Stroke Hyperglycemia Insulin Network Effort (SHINE) trial.
In this post-hoc analysis, we analyzed patients enrolled into the SHINE trial with anterior circulation large vessel occlusion who underwent imaging with CT angiography prior to glucose control treatment group assignment. The primary analysis assessed the degree to which collateral status modified the effect between treatment group and functional outcome as defined by the 90-day modified Rankin Scale score. Logistic regression was used to model the data, with adjustments made for thrombectomy status, age, post-perfusion thrombolysis in cerebral infarction (TICI) score, tissue plasminogen activator (tPA) use, and baseline National Institutes of Health Stroke Scale (NIHSS) score. Five SHINE trial centers contributed data for this analysis. Statistical significance was defined as a p-value < 0.05.
Among the 1151 patients in the SHINE trial, 57 with angiographic data were included in this sub-analysis, of whom 19 had poor collaterals and 38 had good collaterals. While collateral status had no effect (p = 0.855) on the association between glucose control treatment group and functional outcome, patients with good collaterals were more likely to have a favorable functional outcome (p = 0.001, OR 5.02; 95% CI 1.37-16.0).
In a post-hoc analysis using a subset of patients with angiographic data enrolled in the SHINE trial, collateral status did not modify the association between glucose control treatment group and functional outcome. However, consistent with prior studies, there was a significant association between good collateral status and favorable outcome in patients with large vessel occlusion stroke.
ClinicalTrials.gov Identifier is NCT01369069. Registration date is June 8, 2011.
Background and Purpose- Although cigarette use may be a risk for intracerebral hemorrhage (ICH), animal models suggest that nicotine has a potential neuroprotective effect. The aim of this ...multicenter study is to determine the effect of smoking history on outcome in ICH patients. Methods- We analyzed prospectively collected data from the Ethnic/Racial Variations of Intracerebral Hemorrhage study and included patients with smoking status data in the analysis. Patients were dichotomized into nonsmokers versus ever-smokers, and the latter group was further categorized as former (>30 days before ICH) or current (≤30 days before ICH) smokers. The primary outcome was 90-day modified Rankin Scale score shift analysis. Secondary outcomes were in-hospital mortality and mortality, Barthel Index, and self-reported health status measures at 90 days. Results- The overall study cohort comprised 1509 nonsmokers and 1423 ever-smokers (841 former, 577 current, 5 unknown). No difference in primary outcome was observed between nonsmokers versus ever-smokers (adjusted odds ratio aOR, 1.041; 95% CI, 0.904-1.199; P=0.577). No differences in primary outcome were observed between former (aOR, 0.932; 95% CI, 0.791-1.178; P=0.399) or current smokers (aOR, 1.178; 95% CI, 0.970-1.431; P=0.098) versus nonsmokers. Subgroup analyses by race/ethnicity demonstrated no differences in primary outcome when former and current smokers were compared with nonsmokers. Former, but not current, smokers had a lower in-hospital mortality rate (aOR, 0.695; 95% CI, 0.500-0.968; P=0.031), which was only observed in Hispanics (aOR, 0.533; 95% CI, 0.309-0.921; P=0.024). Differences in self-reported health status measures were only observed in whites. Conclusions- Cigarette smoking history does not seem to provide a beneficial effect on 90-day functional outcome in patients with ICH.
With ongoing advancements in noninvasive vascular imaging and high-throughput genomics, we have the opportunity to reclassify the cerebrocervical disorders by these shared associations, rather than ...their downstream events, and to better understand etiology, mechanism and preventive treatments going forward.
The common nonatherosclerotic, large-vessel arteriopathies affecting the cerebrovasculature include intracranial aneurysms, cervical artery dissection, fibromuscular dysplasia and moyamoya disease. Together, these entities contribute to a high incidence of devastating cerebrovascular outcomes, including ischemic stroke and subarachnoid hemorrhage, leading to long-term physical and cognitive disability frequently in young otherwise healthy adults. In addition to well reported clinical overlap, these polygenic phenotypes share epidemiological characteristics, environmental risk and a common pathological weakening of the arterial wall.
We reviewed both past and present studies relating these shared associations, including reported candidate gene analyses and genome-wide association data. We also catalogue recent descriptions of novel arteriopathic syndromes that add to the growing list of monogenic connective tissue disease affecting the arterial wall, and further inform our understanding of more common polygenic phenotypes. We also place these cerebrocervical arteriopathies in the context of other systemic nonatherosclerotic, large-vessel vascular disease (e.g. aortic aneurysm and dissection).
PDF
