Combined Use of X-ray Angiography and Intraprocedural MRI Enables Tissue-based Decision Making Regarding Revascularization during Acute Ischemic Stroke Intervention.

Background For patients with acute ischemic stroke undergoing endovascular mechanical thrombectomy with x-ray angiography, the use of adjuncts to maintain vessel patency, such as stents or antiplatelet medications, can increase risk of periprocedural complications. Criteria for using these adjuncts are not well defined. Purpose To evaluate use of MRI to guide critical decision making by using a combined biplane x-ray neuroangiography 3.0-T MRI suite during acute ischemic stroke intervention. Materials and Methods This retrospective observational study evaluated consecutive patients undergoing endovascular intervention for acute ischemic stroke between July 2019 and May 2020 who underwent either angiography with MRI or angiography alone. Cerebral tissue viability was assessed by using MRI as the reference standard. For statistical analysis, Fisher exact test and Student t test were used to compare groups. Results Of 47 patients undergoing acute stroke intervention, 12 patients (median age, 69 years; interquartile range, 60-77 years; nine men) underwent x-ray angiography with MRI whereas the remaining 35 patients (median age, 80 years; interquartile range, 68-86 years; 22 men) underwent angiography alone. MRI results influenced clinical decision making in one of three ways: whether or not to perform initial or additional mechanical thrombectomy, whether or not to place an intracranial stent, and administration of antithrombotic or blood pressure medications. In this initial experience, decision making during endovascular acute stroke intervention in the combined angiography-MRI suite was better informed at MRI, such that therapy was guided in real time by the viability of the at-risk cerebral tissue. Conclusion Integrating intraprocedural 3.0-T MRI into acute ischemic stroke treatment was feasible and guided decisions of whether or not to continue thrombectomy, to place stents, or to administer antithrombotic medication or provide blood pressure medications. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Lev and Leslie-Mazwi in this issue.

Minimally invasive surgery for intracerebral hemorrhage.

PURPOSE OF REVIEW: Spontaneous intracerebral hemorrhage (ICH) is common, associated with a high degree of mortality and long-term functional impairment, and remains without effective proven treatments. Surgical hematoma evacuation can reduce mass effect and decrease cytotoxic effects from blood product breakdown. However, results from large clinical trials that have examined the role of open craniotomy have not demonstrated a significant outcome benefit over medical management. We review the data on minimally invasive surgery (MIS) that is emerging as a treatment modality for spontaneous ICH. RECENT FINDINGS: The use of MIS for supratentorial ICH has increased significantly in recent years and appears to be associated with decreased mortality and improved functional outcome compared with medical management. The role of MIS for posterior fossa ICH is ill-defined. Currently available MIS devices allow for stereotactic aspiration and thrombolysis, endoport-mediated evacuation, and endoscopic aspiration. Clinical series demonstrate that MIS can facilitate significant hematoma volume reduction and may be associated with less morbidity than conventional open surgical approaches. SUMMARY: MIS is an appealing treatment modality for supratentorial ICH and with careful patient selection and technologic advances has the potential to improve neurologic outcomes and reduce mortality. Early and extensive hematoma evacuation are important therapeutic targets and current studies are underway that have the potential to change the management for ICH patients.

Hematoma Expansion Differences in Lobar and Deep Primary Intracerebral Hemorrhage.

BACKGROUND: Hematoma expansion (HE) after intracerebral hemorrhage (ICH) is associated with worse outcome. Lobar ICHs are known to have better outcomes compared to deep ICH; however, it is unclear whether there are HE differences between these locations. We sought to investigate the hypothesis that lobar ICH has less HE compared to deep ICH. METHODS: Primary ICH patients admitted between 2009 and 2016 were included in a prospective single-center ICH cohort study. Patients with preceding anticoagulant use, coagulopathy on admission labs, or presenting after 24 h from symptom onset were excluded. Lobar and deep ICH patients with baseline and follow-up computed tomography (CT) (within 24 h of admission CT) were evaluated. HE was defined primarily as relative growth > 33% given expected baseline hematoma volume differences between locations. Other commonly utilized definitions of HE: > 6 mL, and > 33% or > 6 mL, were additionally assessed. Multivariable logistic regression was used to assess the association of ICH location with HE while adjusting for previously identified covariates of HE. RESULTS: There were 59 lobar and 143 deep ICH patients analyzed. Lobar ICH patients had significantly larger baseline hematoma volumes, lower admission systolic blood pressure, and longer times to admission CT compared to deep ICH. Multivariable logistic regression revealed an association of lobar ICH with lower odds of HE (> 33%) [odds ratio (OR) 0.32; 95% confidence interval (CI) 0.11-0.93; p = 0.04] compared to deep ICH after adjusting for baseline ICH volume, blood pressure, and time to CT. Secondary analysis did not identify an association of lobar ICH with HE defined as > 6 mL (adjusted OR 1.44; 95% CI 0.59-3.50; p = 0.41) or > 33% or > 6 mL (adjusted OR 0.71; 95% CI 0.29-1.70; p = 0.44). CONCLUSION: We identified less HE in lobar compared to deep ICH. The use of absolute growth thresholds in defining HE may be limited when assessing groups with largely different baseline hematoma sizes. Further study is required to replicate our findings and investigate mechanisms for HE differences between lobar and deep ICH locations.

ABO Blood Type and Hematoma Expansion After Intracerebral Hemorrhage: An Exploratory Analysis.

BACKGROUND/PURPOSE: Blood type has become an increasingly recognized risk factor for coagulopathy. We explored the association between blood type and hematoma expansion (HE) after intracerebral hemorrhage (ICH). METHODS: Spontaneous ICH patients prospectively enrolled in an ongoing ICH cohort study at Columbia University Irving Medical Center from 2009 to 2016 were evaluated. Primary ICH patients with admission blood type testing were evaluated for HE differences, defined as > 33% relative HE. The association of blood type with radiographic HE outcomes was assessed using multivariable logistic regression models. The association of blood type and poor clinical outcomes using modified Rankin Scale (mRS 4-6) was additionally explored. RESULTS: Of 272 ICH patients with blood type data and neuroimaging available to determine HE, there were 146 (54%) type-O, 82 (30%) type-A, 34 (13%) type-B, and 10 (3%) type-AB patients. No significant baseline demographic, clinical, or radiographic differences were noted between blood types. Type-B blood was associated with more HE compared to other blood types (OR 2.82; 95% CI 1.23-6.45) after adjusting for known covariates of HE (anticoagulant use, time to admission computed tomography scan, and baseline hematoma volume). No associations with blood type and poor 3 month mRS were identified, but these analyses were limited secondary to our smaller cohort. CONCLUSIONS: There may be differences in HE after ICH in patients with different blood types. Further work is required to replicate these findings and identify the pathophysiologic mechanisms behind coagulopathy between blood types after ICH.

First Pass Effect: A New Measure for Stroke Thrombectomy Devices.

BACKGROUND AND PURPOSE: In acute ischemic stroke, fast and complete recanalization of the occluded vessel is associated with improved outcomes. We describe a novel measure for newer generation devices: the first pass effect (FPE). FPE is defined as achieving a complete recanalization with a single thrombectomy device pass. METHODS: The North American Solitaire Acute Stroke Registry database was used to identify a FPE subgroup. Their baseline features and clinical outcomes were compared with non-FPE patients. Clinical outcome measures included 90-days modified Rankin Scale score, National Institutes of Health Stroke Scale score, mortality, and symptomatic intracranial hemorrhage. Multivariate analyses were performed to determine whether FPE independently resulted in improved outcomes and to identify predictors of FPE. RESULTS: A total of 354 acute ischemic stroke patients underwent thrombectomy in the North American Solitaire Acute Stroke registry. FPE was achieved in 89 out of 354 (25.1%). More middle cerebral artery occlusions (64% versus 52.5%) and fewer internal carotid artery occlusions (10.1% versus 27.7%) were present in the FPE group. Balloon guide catheters were used more frequently with FPE (64.0% versus 34.7%). Median time to revascularization was significantly faster in the FPE group (median 34 versus 60 minutes; P=0.0003). FPE was an independent predictor of good clinical outcome (modified Rankin Scale score ≤2 was seen in 61.3% in FPE versus 35.3% in non-FPE cohort; P=0.013; odds ratio, 1.7; 95% confidence interval, 1.1-2.7). The independent predictors of achieving FPE were use of balloon guide catheters and non-internal carotid artery terminus occlusion. CONCLUSIONS: The achievement of complete revascularization from a single Solitaire thrombectomy device pass (FPE) is associated with significantly higher rates of good clinical outcome. The FPE is more frequently associated with the use of balloon guide catheters and less likely to be achieved with internal carotid artery terminus occlusion.

Primary Intracerebral Hemorrhage: A Closer Look at Hypertension and Cerebral Amyloid Angiopathy.

BACKGROUND/PURPOSE: Primary intracerebral hemorrhage (ICH) studies often use hematoma location rather than ICH etiologies when assessing outcome. Characterizing ICH using hematoma location is effective/reproducible, but may miss heterogeneity among these ICH locations, particularly lobar ICH where competing primary ICH etiologies are possible. We subsequently investigated baseline characteristics/outcome differences of spontaneous, primary ICH by their etiologies: cerebral amyloid angiopathy (CAA) and hypertension. METHODS: Primary ICH clinical/outcomes data were prospectively collected between 2009 and 2015. Modified Boston criteria were used to identify "probable/definite" and "possible" CAA-ICH, which were evaluated separately. SMASH-U criteria were used to identify hypertension ICH. Medication and systemic disease coagulopathy ICH were excluded. Baseline characteristics/outcomes among "probable/definite" CAA-ICH, "possible" CAA-ICH, and hypertension ICH were compared using logistic regression. Mortality models using ICH etiologies compared to hematoma location as predictor variables were assessed. RESULTS: Two hundred and four hypertension ICHs, 55 "probable/definite" CAA-ICHs, and 46 "possible" CAA-ICHs were identified. Despite older age and larger ICH volumes, lower hospital mortality was seen in "probable/definite" CAA-ICH versus hypertension ICH (OR 0.2; 95% CI 0.05-0.8; p = 0.02) after adjusting for female gender, components of ICH score, and EVD placement. There were no mortality differences between "possible" CAA-ICH and hypertension ICH. However, lower hospital mortality was seen in "probable/definite" versus "possible" CAA-ICH (OR 0.2; 95% CI 0.04-0.7; p = 0.02). When using ICH etiology rather than hematoma location, hospital mortality models significantly improved (χ2: [df = 2, N = 305] = 6.2; p = 0.01). CONCLUSIONS: Further investigation is required to confirm the mortality heterogeneity seen within our primary ICH cohort. Hematoma location may play a role for these findings, but the mortality differences seen among lobar ICH using CAA-ICH subtypes and a failure to identify mortality differences between "possible" CAA-ICH and hypertension ICH suggest the limitations of accounting for hematoma location alone.

A novel approach to diagnose reversible cerebral vasoconstriction syndrome: a case series.

BACKGROUND: Reversible cerebral vasoconstriction syndrome (RCVS) is classically diagnosed based on the presence of severe thunderclap headache, focal neurologic symptoms, and the radiographic findings of reversible diffuse segmental cerebral vasoconstriction. We present a diagnostic test that may assist in the clinical diagnosis and facilitate treatment. METHODS: From October 1, 2010, to August 1, 2013, we identified consecutive patients who presented with a presumptive diagnosis of RCVS and underwent cerebral diagnostic angiography with intra-arterial (IA) vasodilator therapy. Medical records including clinical presentation, radiographic, and angiographic images were all reviewed. RESULTS: We identified a total of 7 patients (4 females; age range, 22-56; mean, 45 years) who met our inclusion criteria. Four patients received a combination of milrinone and nicardipine infusion either in the internal carotid arteries or in the left vertebral artery; the remaining patients received IA therapy solely with either nicardipine or milrinone. Five patients had a positive angiographic response, defined as significant improvement or resolution of the blood vessels irregularities. All 5 patients had a definite discharge diagnosis of RCVS. The remaining 2 patients had a negative angiographic response and based on their clinical and radiographic course had a final diagnosis of intracranial atherosclerotic disease. CONCLUSIONS: Our small case series suggest that IA administration of vasodilators is safe and may aid in distinguishing vasodilator responsive syndromes such as RCVS from other causes. Further study is required with long-term clinical outcome to determine the utility of this diagnostic test.

"Picture to puncture": a novel time metric to enhance outcomes in patients transferred for endovascular reperfusion in acute ischemic stroke.

BACKGROUND: Comprehensive stroke centers allow for regionalization of subspecialty stroke care. Efficacy of endovascular treatments, however, may be limited by delays in patient transfer. Our goal was to identify where these delays occurred and to assess the impact of such delays on patient outcome. METHODS AND RESULTS: This was a retrospective study evaluating patients treated with endovascular therapy from November 2010 to July 2012 at our institution. We compared patients transferred from outside hospitals with locally treated patients with respect to demographics, imaging, and treatment times. Good outcomes, as defined by 90-day modified Rankin Scale scores of 0 to 2, were analyzed by transfer status as well as time from initial computed tomography to groin puncture ("picture-to-puncture" time). A total of 193 patients were analyzed, with a mean age of 65.8 ± 14.5 years and median National Institutes of Health Stroke Scale score of 19 (interquartile range, 15-23). More than two thirds of the patients (132 [68%]) were treated from referring facilities. Outside transfers were noted to have longer picture-to-puncture times (205 minutes [interquartile range, 162-274] versus 89 minutes [interquartile range, 70-119]; P<0.001), which was attributable to the delays in transfer. This corresponded to fewer patients with favorable Alberta Stroke Program Early CT Scores on preprocedural computed tomographic imaging (Alberta Stroke Program Early CT Scores >7: 50% versus 76%; P<0.001) and significantly worse clinical outcomes (29% versus 51%; P=0.003). In a logistic regression model, picture-to-puncture times were independently associated with good outcomes (odds ratio, 0.994; 95% confidence interval, 0.990-0.999; P=0.009). CONCLUSIONS: Delays in picture-to-puncture times for interhospital transfers reduce the probability of good outcomes among treated patients. Strategies to reduce such delays herald an opportunity for hospitals to improve patient outcomes.

Pittsburgh outcomes after stroke thrombectomy score predicts outcomes after endovascular therapy for anterior circulation large vessel occlusions.

BACKGROUND AND PURPOSE: Prognostication tools that predict good outcome in patients with anterior circulation large vessel occlusions after endovascular therapy are lacking. We aim to develop a tool that incorporates clinical and imaging data to predict outcomes after endovascular therapy. METHODS: In a derivation cohort of anterior circulation large vessel occlusion stroke patients treated with endovascular therapy within 8 hours from time last seen well (n=247), we performed logistic regression to identify independent predictors of good outcome (90-day modified Rankin Scale, 0-2). Factors were weighted based on ß-coefficients to derive the Pittsburgh Outcomes After Stroke Thrombectomy (POST) score. POST was validated in an institutional endovascular database (University of Pittsburgh Medical Center, n=393) and the Diffusion-Weighted Imaging Evaluation for Understanding Stroke Evolution Study-2 (DEFUSE-2) data set (n=105), as well as in patients treated beyond 8 hours (n=194) and in octogenarians (n=111). RESULTS: In the derivation cohort, independent predictors (P<0.1) of good outcome included 24- to 72-hour final infarct volume (in cm(3), P<0.001), age (years, P<0.001), and parenchymal hematoma types 1 and 2 (H, P=0.01). POST was calculated as age+0.5×final infarct volume+15×H. Patients with POST score <60 had a 91% chance of good outcome compared with 4% with POST score ≥120. POST accurately predicted good outcomes in the derivation (area under the curve [AUC]=0.85) and validation cohorts (University of Pittsburgh Medical Center, AUC=0.81; DEFUSE-2, AUC=0.86), as well as in patients treated beyond 8 hours (AUC, 0.85) and octogenarians (AUC=0.76). POST had better predictive accuracy for good and poor outcome than the ischemic stroke predictive risk score (iSCORE). CONCLUSIONS: POST score is a validated predictor of outcome in patients with anterior circulation large vessel occlusions after endovascular therapy.

Influence of age on clinical and revascularization outcomes in the North American Solitaire Stent-Retriever Acute Stroke Registry.

BACKGROUND AND PURPOSE: The Solitaire With the Intention for Thrombectomy (SWIFT) and thrombectomy revascularization of large vessel occlusions in acute ischemic stroke (TREVO 2) trial results demonstrated improved recanalization rates with mechanical thrombectomy; however, outcomes in the elderly population remain poorly understood. Here, we report the effect of age on clinical and angiographic outcome within the North American Solitaire-FR Stent-Retriever Acute Stroke (NASA) Registry. METHODS: The NASA Registry recruited sites to submit data on consecutive patients treated with Solitaire-FR. Influence of age on clinical and angiographic outcomes was assessed by dichotomizing the cohort into ≤80 and >80 years of age. RESULTS: Three hundred fifty-four patients underwent treatment in 24 centers; 276 patients were ≤80 years and 78 were >80 years of age. Mean age in the ≤80 and >80 cohorts was 62.2±13.2 and 85.2±3.8 years, respectively. Of patients >80 years, 27.3% had a 90-day modified Rankin Score ≤2 versus 45.4% ≤80 years (P=0.02). Mortality was 43.9% and 27.3% in the >80 and ≤80 years cohorts, respectively (P=0.01). There was no significant difference in time to revascularization, revascularization success, or symptomatic intracranial hemorrhage between the groups. Multivariate analysis showed age >80 years as an independent predictor of poor clinical outcome and mortality. Within the >80 cohort, National Institutes of Health Stroke Scale (NIHSS), revascularization rate, rescue therapy use, and symptomatic intracranial hemorrhage were independent predictors of mortality. CONCLUSION: Greater than 80 years of age is predictive of poor clinical outcome and increased mortality compared with younger patients in the NASA registry. However, intravenous tissue-type plasminogen activator use, lower NIHSS, and shorter revascularization time are associated with better outcomes. Further studies are needed to understand the endovascular therapy role in this cohort compared with medical therapy.

North American SOLITAIRE Stent-Retriever Acute Stroke Registry: choice of anesthesia and outcomes.

BACKGROUND AND PURPOSE: Previous work that predated the availability of the safer stent-retriever devices has suggested that general anesthesia (GA) may have a negative impact on outcomes in patients with acute ischemic stroke undergoing endovascular therapy. METHODS: We reviewed demographic, clinical, procedural (GA versus local anesthesia [LA], etc), and site-adjudicated angiographic and clinical outcomes data from consecutive patients treated with the Solitaire FR device in the investigator-initiated North American SOLITAIRE Stent-Retriever Acute Stroke (NASA) Registry. The primary outcomes were 90-day modified Rankin Scale, mortality, and symptomatic intracranial hemorrhage. RESULTS: A total of 281 patients from 18 centers were enrolled. GA was used in 69.8% (196/281) of patients. Baseline demographic and procedural factors were comparable between the LA and GA groups, except the former demonstrated longer time-to-groin puncture (395.4±254 versus 337.4±208 min; P=0.04), lower National Institutes of Health Stroke Scale (NIHSS; 16.2±5.8 versus 18.8±6.9; P=0.002), lower balloon-guide catheter usage (22.4% versus 49.2%; P=0.0001), and longer fluoroscopy times (39.5±33 versus 28±22.8 min; P=0.008). Recanalization (thrombolysis in cerebral infarction ≥2b; 72.94% versus 73.6%; P=0.9) and rate of symptomatic intracranial hemorrhage (7.1% versus 11.2%; P=0.4) were similar but modified Rankin Scale ≤2 was achieved in more LA patients, 52.6% versus 35.6% (odds ratio, 1.4 [1.1-1.8]; P=0.01). In multivariate analysis, hypertension, NIHSS, unsuccessful revascularization, and GA use (odds ratio, 3.3 [1.6-7.1]; P=0.001) were associated with death. When only anterior circulation and elective GA patients were included, there was a persistent difference in good outcomes in favor of LA patients (50.7% versus 35.5%; odds ratio, 1.3 [1.01-1.6]; P=0.04). CONCLUSIONS: The NASA Registry has demonstrated that clinical outcomes and survival are significantly better in patients treated with LA, without increased symptomatic intracranial hemorrhage risk. Future trials should prospectively evaluate the effect of GA on outcomes.

Balloon guide catheter improves revascularization and clinical outcomes with the Solitaire device: analysis of the North American Solitaire Acute Stroke Registry.

BACKGROUND AND PURPOSE: Efficient and timely recanalization is an important goal in acute stroke endovascular therapy. Several studies demonstrated improved recanalization and clinical outcomes with the stent retriever devices compared with the Merci device. The goal of this study was to evaluate the role of the balloon guide catheter (BGC) and recanalization success in a substudy of the North American Solitaire Acute Stroke (NASA) registry. METHODS: The investigator-initiated NASA registry recruited 24 clinical sites within North America to submit demographic, clinical, site-adjudicated angiographic, and clinical outcome data on consecutive patients treated with the Solitaire Flow Restoration device. BGC use was at the discretion of the treating physicians. RESULTS: There were 354 patients included in the NASA registry. BGC data were reported in 338 of 354 patients in this subanalysis, of which 149 (44%) had placement of a BGC. Mean age was 67.3±15.2 years, and median National Institutes of Health Stroke Scale score was 18. Patients with BGC had more hypertension (82.4% versus 72.5%; P=0.05), atrial fibrillation (50.3% versus 32.8%; P=0.001), and were more commonly administered tissue plasminogen activator (51.6% versus 38.8%; P=0.02) compared with patients without BGC. Time from symptom onset to groin puncture and number of passes were similar between the 2 groups. Procedure time was shorter in patients with BGC (120±28.5 versus 161±35.6 minutes; P=0.02), and less adjunctive therapy was used in patients with BGC (20% versus 28.6%; P=0.05). Thrombolysis in cerebral infarction 3 reperfusion scores were higher in patients with BGC (53.7% versus 32.5%; P<0.001). Distal emboli and emboli in new territory were similar between the 2 groups. Discharge National Institutes of Health Stroke Scale score (mean, 12±14.5 versus 17.5±16; P=0.002) and good clinical outcome at 3 months were superior in patients with BGC compared with patients without (51.6% versus 35.8%; P=0.02). Multivariate analysis demonstrated that the use of BGC was an independent predictor of good clinical outcome (odds ratio, 2.5; 95% confidence interval, 1.2-4.9). CONCLUSIONS: Use of a BGC with the Solitaire Flow Restoration device resulted in superior revascularization results, faster procedure times, decreased need for adjunctive therapy, and improved clinical outcome.

Optimizing prediction scores for poor outcome after intra-arterial therapy in anterior circulation acute ischemic stroke.

BACKGROUND AND PURPOSE: Intra-arterial therapy (IAT) promotes recanalization of large artery occlusions in acute ischemic stroke. Despite high recanalization rates, poor clinical outcomes are common. We attempted to optimize a score that combines clinical and imaging variables to more accurately predict poor outcome after IAT in anterior circulation occlusions. METHODS: Patients with acute ischemic stroke undergoing IAT at University of Texas (UT) Houston for large artery occlusions (middle cerebral artery or internal carotid artery) were reviewed. Independent predictors of poor outcome (modified Rankin Scale, 4-6) were studied. External validation was performed on IAT-treated patients at Emory University. RESULTS: A total of 163 patients were identified at UT Houston. Independent predictors of poor outcome (P≤0.2) were identified as score variables using sensitivity analysis and logistic regression. Houston Intra-Arterial Therapy 2 (HIAT2) score ranges 0 to 10: age (≤59=0, 60-79=2, ≥80 years=4), glucose (<150=0, ≥150=1), National Institute Health Stroke Scale (≤10=0, 11-20=1, ≥21=2), the Alberta Stroke Program Early CT Score (8-10=0, ≤7=3). Patients with HIAT2≥5 were more likely to have poor outcomes at discharge (odds ratio, 6.43; 95% confidence interval, 2.75-15.02; P<0.001). After adjusting for reperfusion (Thrombolysis in Cerebral Infarction score≥2b) and time from symptom onset to recanalization, HIAT2≥5 remained an independent predictor of poor outcome (odds ratio, 5.88; 95% confidence interval, 1.96-17.64; P=0.02). Results from the cohort of Emory (198 patients) were consistent; patients with HIAT2 score≥5 had 6× greater odds of poor outcome at discharge and at 90 days. HIAT2 outperformed other previously published predictive scores. CONCLUSIONS: The HIAT2 score, which combines clinical and imaging variables, performed better than all previous scores in predicting poor outcome after IAT for anterior circulation large artery occlusions.

Hyper-Acute Necrotizing Encephalopathy-Like Syndrome in Early Pregnancy.

Acute necrotizing encephalopathy (ANE) is a rare and life-threatening disease. It is caused by a cytokine-mediated injury to the brain with characteristic hemorrhagic and edematous lesions involving the bilateral thalami, brainstem, and other subcortical structures. The disease is commonly associated with antecedent viral triggers such as influenza, parainfluenza, and more recently, SARS-CoV-2, with subsequent neurologic deterioration occurring within days to weeks. Here, we present a case of a pregnant adult woman who developed a hyperacute form of ANE, progressing to brain death within 36 hours of symptom onset. Her diagnosis was confirmed via brain imaging, CSF studies, and neurohistopathological analysis. This case highlights the importance of establishing an early diagnosis for this under-recognized disease, and also suggests an association between ANE and early pregnancy.

Resilience to Injury: A New Approach to Neuroprotection?

Despite thousands of neuroprotectants demonstrating promise in preclinical trials, a neuroprotective therapeutic has yet to be approved for the treatment of acute brain injuries such as stroke or traumatic brain injury. Developing a more detailed understanding of models and populations demonstrating "neurological resilience" in spite of brain injury can give us important insights into new translational therapies. Resilience is the process of active adaptation to a stressor. In the context of neuroprotection, models of preconditioning and unique animal models of extreme physiology (such as hibernating species) reliably demonstrate resilience in the laboratory setting. In the clinical setting, resilience is observed in young patients and can be found in those with specific genetic polymorphisms. These important examples of resilience can help transform and extend the current neuroprotective framework from simply countering the injurious cascade into one that anticipates, monitors, and optimizes patients' physiological responses from the time of injury throughout the process of recovery. This review summarizes the underpinnings of key adaptations common to models of resilience and how this understanding can be applied to new neuroprotective approaches.

North American Solitaire Stent Retriever Acute Stroke registry: post-marketing revascularization and clinical outcome results.

BACKGROUND: Limited post-marketing data exist on the use of the Solitaire FR device in clinical practice. The North American Solitaire Stent Retriever Acute Stroke (NASA) registry aimed to assess the real world performance of the Solitaire FR device in contrast with the results from the SWIFT (Solitaire with the Intention for Thrombectomy) and TREVO 2 (Trevo versus Merci retrievers for thrombectomy revascularization of large vessel occlusions in acute ischemic stroke) trials. METHODS: The investigator initiated NASA registry recruited North American sites to submit retrospective angiographic and clinical outcome data on consecutive acute ischemic stroke (AIS) patients treated with the Solitaire FR between March 2012 and February 2013. The primary outcome was a Thrombolysis in Myocardial Ischemia (TIMI) score of ≥2 or a Treatment in Cerebral Infarction (TICI) score of ≥2a. Secondary outcomes were 90 day modified Rankin Scale (mRS) score, mortality, and symptomatic intracranial hemorrhage. RESULTS: 354 patients underwent treatment for AIS using the Solitaire FR device in 24 centers. Mean time from onset to groin puncture was 363.4±239 min, mean fluoroscopy time was 32.9±25.7 min, and mean procedure time was 100.9±57.8 min. Recanalization outcome: TIMI ≥2 rate of 83.3% (315/354) and TICI ≥2a rate of 87.5% (310/354) compared with the operator reported TIMI ≥2 rate of 83% in SWIFT and TICI ≥2a rate of 85% in TREVO 2. Clinical outcome: 42% (132/315) of NASA patients demonstrated a 90 day mRS ≤2 compared with 37% (SWIFT) and 40% (TREVO 2). 90 day mortality was 30.2% (95/315) versus 17.2% (SWIFT) and 29% (TREVO 2). CONCLUSIONS: The NASA registry demonstrated that the Solitaire FR device performance in clinical practice is comparable with the SWIFT and TREVO 2 trial results.

Clinical and Angiographic Outcomes with the Combined Local Aspiration and Retriever in the North American Solitaire Stent-Retriever Acute Stroke (NASA) Registry.

BACKGROUND: Various techniques are used to enhance the results of mechanical thrombectomy with stent-retrievers, including proximal arrest with balloon guide catheter (BGC), conventional large bore proximal catheter (CGC), or in combination with local aspiration through a large-bore catheter positioned at the clot interface (Aspiration-Retriever Technique for Stroke [ARTS]). We evaluated the impact of ARTS in the North American Solitaire Acute Stroke (NASA) registry. SUMMARY: Data on the use of the aspiration technique were available for 285 anterior circulation patients, of which 29 underwent ARTS technique, 131 CGC, and 125 BGC. Baseline demographics were comparable, except that ARTS patients are less likely to have hypertension or atrial fibrillation. The ARTS group had more ICA occlusions (41.4 vs. 22% in the BGC, p = 0.04 and 26% in CGC, p = 0.1) and less MCA/M1 occlusions (44.8 vs. 68% in BGC and 62% in CGC). Time from arterial puncture to reperfusion or end of procedure with ARTS was shorter than with CGC (54 vs. 91 min, p = 0.001) and was comparable to the BGC time (54 vs. 67, p = 0.11). Final degree of reperfusion was comparable among the groups (TICI [modified Thrombolysis in Cerebral Infarction] score 2b or higher was 72 vs. 70% for CGC vs. 78% for BGC). Procedural complications, mortality, and good clinical outcome at 90 days were similar between the groups. KEY MESSAGES: The ARTS mechanical thrombectomy in acute ischemic stroke patients appears to yield better results as compared to the use of CGCs with no significant difference when compared to BGC. This early ARTS technique NASA registry data are limited by the earlier generation distal large bore catheters and small sample size. Future studies should focus on the comparison of ARTS and BGC techniques.

Presence of the hyperintense acute reperfusion marker on MRI after mechanical thrombectomy for large vessel occlusion is associated with worse early neurological recovery.

BACKGROUND: Mechanical thrombectomy has become the accepted treatment for large vessel occlusion in acute ischemic stroke. Unfortunately, a large cohort of patients do not achieve functional independence with treatment, even though the results are more robust than with medical management. The hyperintense acute reperfusion marker (HARM) on MRI is an indication of the breakdown of the blood-brain barrier and reperfusion injury. OBJECTIVE: To examine the hypothesis that the presence of HARM on MRI correlates with worse neurological recovery after reperfusion therapy. METHODS: We retrospectively reviewed 35 consecutive patients who between February 24, 2016 and April 23, 2016 underwent MRI to determine the presence of HARM after thrombectomy for anterior circulation large vessel occlusion. Demographic, radiographic imaging, and outcome data were collected. Univariate and binary logistic regression models were performed to assess predictors for improvement of the National Institutes of Health Stroke Scale (NIHSS) score by ≥8 points at 24 hours. RESULTS: The 35 patients studied had an average age of 64±14 years of age with a median NIHSS score of 15 (IQR 9-20). Eighteen patients (51%) were found to have a HARM-positive MRI. In univariate analysis, patients with HARM were older, had lower reperfusion rates and more postprocedural hemorrhages. In binary logistic regression modeling, the absence of HARM was independently associated with a ≥8-point NIHSS score improvement at 24 hours (OR=7.14, 95% CI 1.22 to 41.67). CONCLUSIONS: This preliminary analysis shows that the presence of HARM may be linked to worse neurological recovery 24 hours after thrombectomy. Reperfusion injury may affect the number of patients achieving functional independence after treatment.

Complete reperfusion mitigates influence of treatment time on outcomes after acute stroke.

BACKGROUND: Time to reperfusion following endovascular treatment (ET) predicts outcomes after acute ischemic stroke (AIS). OBJECTIVE: To assess the time-outcome relationship within reperfusion grades in the North American Solitaire Acute Stroke registry. METHODS: We identified patients given ET for anterior circulation ischemic stroke within 8 h from onset and in whom reperfusion was achieved. Together with clinical and outcome data, site-adjudicated modified Thrombolysis in Cerebral Ischemia (TICI) was recorded. We assessed the impact of time to reperfusion (onset to procedure completion time) on good outcome (modified Rankin Scale 0-2 at 3 months) in patients who achieved TICI 2 or higher reperfusion in multivariable models. We further assessed this relationship within strata of reperfusion grades. A p<0.05 was considered significant. RESULTS: Independent predictors of good outcome at 3 months among those achieving TICI ≥2a reperfusion (n=188) were initial National Institutes of Health Stroke Scale score (adjusted OR=0.90, 95% CI 0.85 to 0.95), symptomatic hemorrhage (adj. OR=0.16, 95% CI 0.05 to 0.60), TICI grade (TICI 3: adj. OR=11.52, 95% CI 3.34 to 39.77; TICI 2b: adj. OR=5.14, 95% CI 1.61 to 16.39), and time to reperfusion per 30 min interval (adj. OR=0.91, 95% CI 0.82 to 0.99). There was an interaction between final TICI grade and 30 min time to reperfusion intervals (p=0.001) such that the effect of time was strongest in TICI 2a patients. CONCLUSIONS: Time to reperfusion was a strong predictor of outcome following ET for AIS. However, the effect varied by TICI grade such that its greatest effect was in those achieving TICI 2a reperfusion.