Revolutionizing Intracranial Hemorrhage Diagnosis: A Retrospective Analytical Study of Viz.ai ICH for Enhanced Diagnostic Accuracy.

Introduction Artificial intelligence (AI) alerts the radiologist to the presence of intracranial hemorrhage (ICH) as fast as 1-2 minutes from scan completion, leading to faster diagnosis and treatment. We wanted to validate a new AI application called Viz.ai ICH to improve the diagnosis of suspected ICH. Methods We performed a retrospective analysis of 4,203 consecutive non-contrast brain computed tomography (CT) reports in a single institution between September 1, 2021, and January 31, 2022. The reports were made by neuroradiologists who reviewed each case for the presence of ICH. Reports and identified cases with positive findings for ICH were reviewed. Positive cases were categorized based on subtype, timing, and size/volume. Viz.ai ICH output was reviewed for positive cases. This AI model was validated by assessing its performance with Viz.ai ICH as the index test compared to the neuroradiologists' interpretation as the gold standard. Results According to neuroradiologists, 9.2% of non-contrast brain CT reports were positive for ICH. The sensitivity of Viz.ai ICH was 85%, specificity was 98%, positive predictive value was 81%, and negative predictive value was 99%. Subgroup analysis was performed based on intraparenchymal, subarachnoid, subdural, and intraventricular subtypes. Sensitivities were 94%, 79%, 83%, and 44%, respectively. Further stratification revealed sensitivity improves with higher acuity and volume/size across subtypes. Conclusion Our analysis indicates that AI can accurately detect ICH's presence, particularly for large-volume/large-size ICH. The paper introduces a novel AI model for detecting ICH. This advancement contributes to the field by revolutionizing ICH detection and improving patient outcomes.

Management of failed flow diversion for intracranial aneurysm beyond the first 6 months of follow-up: an international Delphi consensus.

OBJECTIVE: The placement of flow-diverting devices has become a common method of treating unruptured intracranial aneurysms of the internal carotid artery. The progressive improvement of aneurysm occlusion after treatment-with low complication and rupture rates-has led to a dilemma regarding the management of aneurysms in which occlusion has not occurred within 6-24 months. The authors aimed to identify clinical consensus regarding management of intracranial aneurysms displaying persistent filling 6-24 months after flow diversion and to ascertain questions that may drive future investigation. METHODS: An international panel of 67 experts was invited to participate in a multistep Delphi consensus process on the treatment of intracranial aneurysms after failed flow diversion. RESULTS: Of the 67 experts invited, 23 (34%) participated. Qualitative analysis of an initial survey with open-ended questions resulted in 51 statements regarding management of aneurysms showing persistent filling after flow diversion. The statements were grouped into 8 categories, and in the second round, respondents rated the degree of their agreement with each statement on a 5-point Likert scale. Flow diverters with surface modifiers did not influence administration of dual-antiplatelet therapy according to 83%. Consensus was also reached regarding the definition of treatment failure at specific time points, including at 6 months if there is aneurysm growth or persistent rapid flow through the entirety of the aneurysm (96%), at 12 months if there is aneurysm growth or symptom onset (78%), and at 24 months if there is persistent filling regardless of size and filling characteristics (74%). Although experts agreed that the degree of intimal hyperplasia or in-device stenosis could not be ascertained by noninvasive imaging alone (83%), only 65% chose digital subtraction angiography as the preferred modality. At 6 and 12 months, retreatment is preferred if there is persistent filling with aneurysm growth (96%, 96%), device malposition (48%, 87%), or a history of subarachnoid hemorrhage (65%, 70%), respectively, and at 24 months if there is persistent filling without reduction in aneurysm size (74%). Experts favored treatment with an additional flow diverter (87%) over aneurysm clipping, applying the same principles for follow-up (83%) and treatment failure (91%) as for the first flow diverter. CONCLUSIONS: The authors present the consensus practices of experts in the management of intracranial aneurysms without occlusion 6-24 months after treatment with a flow-diverting device.

Rescue Therapy for Failed Mechanical Thrombectomy in Acute Ischemic Stroke: A Pooled Analysis of the Society of Vascular and Interventional Neurology Registry.

OBJECTIVE: We aimed to evaluate the association between rescue therapy (RT) and functional outcomes compared to medical management (MM) in patients presenting after failed mechanical thrombectomy (MT). METHODS: This cross-sectional study utilized prospectively collected and maintained data from the Society of Vascular and Interventional Neurology Registry, spanning from 2011 to 2021. The cohort comprised patients with large vessel occlusions (LVOs) with failed MT. The primary outcome was the shift in the degree of disability, as gauged by the modified Rankin Scale (mRS) at 90 days. Additional outcomes included functional independence (90-day mRS score of 0-2), symptomatic intracranial hemorrhage (sICH), and 90-day mortality. RESULTS: Of a total of 7,018 patients, 958 presented failed MT and were included in the analysis. The RT group comprised 407 (42.4%) patients, and the MM group consisted of 551 (57.5%) patients. After adjusting for confounders, the RT group showed a favorable shift in the overall 90-day mRS distribution (adjusted common odds ratio = 1.79, 95% confidence interval [CI] = 1.32-2.45, p < 0.001) and higher rates of functional independence (RT: 28.8% vs MM: 15.7%, adjusted odds ratio [aOR] = 1.93, 95% CI = 1.21-3.07, p = 0.005) compared to the MM group. RT also showed lower rates of sICH (RT: 3.8% vs MM: 9.1%, aOR = 0.52, 95% CI = 0.28-0.97, p = 0.039) and 90-day mortality (RT: 33.4% vs MM: 45.5%, aOR = 0.61, 95% CI = 0.42-0.89, p = 0.009). INTERPRETATION: Our findings advocate for the utilization of RT as a potential treatment strategy for cases of LVO resistant to first-line MT techniques. Prospective studies are warranted to validate these observations and optimize the endovascular approach for failed MT patients. ANN NEUROL 2024;96:343-355.

Intravenous cangrelor use for neuroendovascular procedures: a two-center experience and updated systematic review.

Background: The optimal antiplatelet therapy regimen for certain neuroendovascular procedures remains unclear. This study investigates the safety and feasibility of intravenous dose-adjusted cangrelor in patients undergoing acute neuroendovascular interventions. Methods: We conducted a retrospective chart review of all consecutive patients on intravenous cangrelor for neuroendovascular procedures between September 1, 2020, and March 13, 2022. We also conducted an updated systematic review and meta-analysis using PubMed, Scopus, Web of Science, Embase and the Cochrane Library up to February 22, 2023. Results: In our cohort, a total of 76 patients were included [mean age (years): 57.2 ± 18.2, males: 39 (51.3), Black: 49 (64.5)]. Cangrelor was most used for embolization and intracranial stent placement (n = 24, 32%). Approximately 44% of our patients had a favorable outcome with a modified Rankin Scale (mRS) score of 0 to 2 at 90 days (n = 25/57); within 1 year, 8% of patients had recurrent or new strokes (n = 5/59), 6% had symptomatic intracranial hemorrhage [sICH] (4/64), 3% had major extracranial bleeding events (2/64), and 3% had a gastrointestinal bleed (2/64). In our meta-analysis, 11 studies with 298 patients were included. The pooled proportion of sICH and intraprocedural thromboembolic complication events were 0.07 [95% CI 0.04 to 1.13] and 0.08 [95% CI 0.05 to 0.15], respectively. Conclusion: Our study found that intravenous cangrelor appears to be safe and effective in neuroendovascular procedures, with low rates of bleeding and ischemic events. However, further research is needed to compare different dosing and titration protocols of cangrelor and other intravenous agents.

No-reflow phenomenon in acute ischemic stroke: an angiographic evaluation.

BACKGROUND: Futile recanalization (FR) is de fined as a poor 90-day outcome or lack of neurological improvement at 24 h despite successful recanalization in acute ischemic stroke (AIS) with large vessel occlusion (LVO) treated by mechanical throbectomy (MT). The No-reflow phenomenon (NRP) could be a possible cause of FR, but its evidence in AIS patients is scarce. METHODS: We retrospectively analyzed 185 digital subtraction angiographies (DSA) of AIS patients with anterior circulation LVO after endovascular treatment. To better define NRP, we designed a score called the modified capillary index score (mCIS). The score is obtained by dividing the middle cerebral artery territory in three segments. For each segment, we gave 2 points if the capillary blush was present without any delay, 1 if delayed, and 0 if absent. The primary endpoint was to use mCIS to identify NRP on post-interventional DSA and to test whether this marker may predict FR and failure of early neurological improvement (fENI). The secondary endpoint was to search for a correlation between NRP, lesion volume, and hemorrhagic transformation. We used the ROC curve to define mCIS ≤ 3 as the cut-off and marker of NRP. RESULTS: NRP was present in 35.1% of patients. NRP predicted fENI at 24 h (aOR 2.825, 95% CI 1.265-6.308, P = 0.011) and at 7 days (aOR 2.191, 95% CI 1.008-4.762, P = 0.048), but not 90-day FR. Moreover, NRP predicted hemorrhagic transformation (aOR 2.444, 95% CI 1.266-4.717, P = 0.008). CONCLUSIONS: The modified capillary index score (mCIS) seems useful in identifying NRP in AIS. In addition, mCIS was able to predict NRP that correlated with early clinical outcome and hemorrhagic transformation of the ischemic lesion. An external validation of the score is warranted.

International controlled study of revascularization and outcomes following COVID-positive mechanical thrombectomy.

BACKGROUND AND PURPOSE: Previous studies suggest that mechanisms and outcomes in patients with COVID-19-associated stroke differ from those in patients with non-COVID-19-associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID-19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors. METHODS: A cross-sectional, international multicenter retrospective study was conducted in consecutively admitted COVID-19 patients with concomitant acute LVO, compared to a control group without COVID-19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable-adjusted analysis was conducted. RESULTS: In this cohort of 697 patients with acute LVO, 302 had COVID-19 while 395 patients did not. There was a significant difference (p < 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID-19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID-19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23-0.48; p < 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12-0.77; p = 0.012). Moreover, endovascular complications, in-hospital mortality, and length of hospital stay were significantly higher among COVID-19 patients (p < 0.001). CONCLUSION: COVID-19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID-19 patients with LVO were more often younger and had higher morbidity/mortality rates.

Characteristics of a COVID-19 Cohort With Large Vessel Occlusion: A Multicenter International Study.

BACKGROUND: The mechanisms and outcomes in coronavirus disease (COVID-19)-associated stroke are unique from those of non-COVID-19 stroke. OBJECTIVE: To describe the efficacy and outcomes of acute revascularization of large vessel occlusion (LVO) in the setting of COVID-19 in an international cohort. METHODS: We conducted an international multicenter retrospective study of consecutively admitted patients with COVID-19 with concomitant acute LVO across 50 comprehensive stroke centers. Our control group constituted historical controls of patients presenting with LVO and receiving a mechanical thrombectomy between January 2018 and December 2020. RESULTS: The total cohort was 575 patients with acute LVO; 194 patients had COVID-19 while 381 patients did not. Patients in the COVID-19 group were younger (62.5 vs 71.2; P < .001) and lacked vascular risk factors (49, 25.3% vs 54, 14.2%; P = .001). Modified thrombolysis in cerebral infarction 3 revascularization was less common in the COVID-19 group (74, 39.2% vs 252, 67.2%; P < .001). Poor functional outcome at discharge (defined as modified Ranklin Scale 3-6) was more common in the COVID-19 group (150, 79.8% vs 132, 66.7%; P = .004). COVID-19 was independently associated with a lower likelihood of achieving modified thrombolysis in cerebral infarction 3 (odds ratio [OR]: 0.4, 95% CI: 0.2-0.7; P < .001) and unfavorable outcomes (OR: 2.5, 95% CI: 1.4-4.5; P = .002). CONCLUSION: COVID-19 was an independent predictor of incomplete revascularization and poor outcomes in patients with stroke due to LVO. Patients with COVID-19 with LVO were younger, had fewer cerebrovascular risk factors, and suffered from higher morbidity/mortality rates.

Acute ischaemic stroke associated with SARS-CoV-2 infection in North America.

BACKGROUND: To analyse the clinical characteristics of COVID-19 with acute ischaemic stroke (AIS) and identify factors predicting functional outcome. METHODS: Multicentre retrospective cohort study of COVID-19 patients with AIS who presented to 30 stroke centres in the USA and Canada between 14 March and 30 August 2020. The primary endpoint was poor functional outcome, defined as a modified Rankin Scale (mRS) of 5 or 6 at discharge. Secondary endpoints include favourable outcome (mRS ≤2) and mortality at discharge, ordinal mRS (shift analysis), symptomatic intracranial haemorrhage (sICH) and occurrence of in-hospital complications. RESULTS: A total of 216 COVID-19 patients with AIS were included. 68.1% (147/216) were older than 60 years, while 31.9% (69/216) were younger. Median [IQR] National Institutes of Health Stroke Scale (NIHSS) at presentation was 12.5 (15.8), and 44.2% (87/197) presented with large vessel occlusion (LVO). Approximately 51.3% (98/191) of the patients had poor outcomes with an observed mortality rate of 39.1% (81/207). Age >60 years (aOR: 5.11, 95% CI 2.08 to 12.56, p<0.001), diabetes mellitus (aOR: 2.66, 95% CI 1.16 to 6.09, p=0.021), higher NIHSS at admission (aOR: 1.08, 95% CI 1.02 to 1.14, p=0.006), LVO (aOR: 2.45, 95% CI 1.04 to 5.78, p=0.042), and higher NLR level (aOR: 1.06, 95% CI 1.01 to 1.11, p=0.028) were significantly associated with poor functional outcome. CONCLUSION: There is relationship between COVID-19-associated AIS and severe disability or death. We identified several factors which predict worse outcomes, and these outcomes were more frequent compared to global averages. We found that elevated neutrophil-to-lymphocyte ratio, rather than D-Dimer, predicted both morbidity and mortality.

Analysis of potential time saving in brain arteriovenous malformation stereotactic radiosurgery planning using a new software platform.

To evaluate the utility of integrating a 3D vessel tree co-registration software platform into the stereotactic radiosurgery (SRS) workflow and its time saving for brain arteriovenous malformation (bAVM) treatment in adults compared to the conventional stereotactic head frame workflow. Eight consecutive adult bAVM cases were selected and retrospectively reviewed. Total number of angiograms and SRS procedures were 8. The electronic medical records were analyzed by time stamps to determine the length of time for each component of the set-up, transport, and frame removal. Times were averaged and the start of sedation by anesthesia used as a surrogate for the start of the frame application process. Reductions in workflow times were then modeled assuming cerebral angiography as a separate procedure. There were 8 adult bAVM cases included. Six were female. All patients had a single treatment session. Average age was 51.5 years (Range: 36-71). All patients were treated under monitored anesthesia care. In 6 patients, the AVM was deeply located (basal ganglia, midbrain, brainstem); in 2 cases, the lesion was frontal. Spetzler-Martin grades were 4 (50%) Grade 2 and 4 (50%) Grade 3. The average prescription isodose volume (PIV) and 12 Gy volumes (V12Gy) were 0.85 cc and 1.74 cc, respectively. The mean time from frame application to arrival in the angiography room was 111.5 minutes (range 40 to 171 min; median 107 min; SD 35.3 min); transport from angiography room to SRS was 47.5 minutes (range 15 to 107 min; median 36 min; SD 31.1 min), and frame removal after SRS was 20.5 minutes (range 10 to 47 min; median 16 min; SD 11.6 min). The average total additional time for the entire process of frame application, patient transportation, and frame removal was 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). Therefore, assuming a non-frame based workflow and with angiography performed ahead of the actual radiosurgical treatment, the total time savings on the day of treatment was estimated at 132 minutes (range 87 to 181 min; median 127.5 min; SD 28.4 min). The ability to perform angiography, image fusion, and treatment planning for the actual day-of-delivery using 3-dimensional vessel tree co-registration could result in significant time savings over traditional workflow practices. Further experience with this system will evaluate its accuracy, reproducibility, and potential broader use in SRS workflow paradigms for the treatment of vascular pathologies. For bAVMs, the benefits of this time savings might allow for streamlined workflows on the day of SRS.

Intravenous alteplase has different effects on the efficacy of aspiration and stent retriever thrombectomy: analysis of the COMPASS trial.

BACKGROUND: There is conflicting evidence on the utility of intravenous (IV) alteplase in patients with emergent large vessel occlusion (ELVO) treated with mechanical thrombectomy (MT). METHODS: This was a post hoc analysis of the COMPASS: a trial of aspiration thrombectomy versus stent retriever thrombectomy as first-line approach for large vessel occlusion. We compared clinical, procedural and angiographic outcomes of patients with and without prior IV alteplase administration. RESULTS: In the COMPASS trial, 235 patients had presented to the hospital within the first 4 hours of stroke symptom onset and were eligible for analysis. On univariate analysis, administration of IV alteplase prior to MT was found to be significantly associated with favorable outcomes (modified Rankin scale (mRS) 0-2 at 3 months; 55.6% vs 40.0% in the MT-only group, P=0.037). However, on multivariate analysis, only baseline (pre-stroke) mRS, admission National Institutes of Health Stroke Scale (NIHSS) score and age were identified as independent predictors of favorable outcomes at 3 months. We found higher final thrombolysis in cerebral infarction (TICI) 2b/3 rates in patients without the use of alteplase prior to the aspiration first approach (100.0% vs 87.9% in IV altepase +aspiration first MT, P=0.03). In the stent retriever first group, final TICI 2b/3 rates were identical in patients with and without IV alteplase administration (87.5% and 87.5%, P=1.0). CONCLUSIONS: Prior administration of IV alteplase may adversely affect the efficacy of aspiration, but does not seem to influence the stent retriever first approach to MT in patients with anterior circulation ELVO.

Endovascular thrombectomy time metrics in the era of COVID-19: observations from the Society of Vascular and Interventional Neurology Multicenter Collaboration.

BACKGROUND: Unprecedented workflow shifts during the coronavirus disease 2019 (COVID-19) pandemic have contributed to delays in acute care delivery, but whether it adversely affected endovascular thrombectomy metrics in acute large vessel occlusion (LVO) is unknown. METHODS: We performed a retrospective review of observational data from 14 comprehensive stroke centers in nine US states with acute LVO. EVT metrics were compared between March to July 2019 against March to July 2020 (primary analysis), and between state-specific pre-peak and peak COVID-19 months (secondary analysis), with multivariable adjustment. RESULTS: Of the 1364 patients included in the primary analysis (51% female, median NIHSS 14 [IQR 7-21], and 74% of whom underwent EVT), there was no difference in the primary outcome of door-to-puncture (DTP) time between the 2019 control period and the COVID-19 period (median 71 vs 67 min, P=0.10). After adjustment for variables associated with faster DTP, and clustering by site, there remained a trend toward shorter DTP during the pandemic (ßadj=-73.2, 95% CI -153.8-7.4, Pp=0.07). There was no difference in DTP times according to local COVID-19 peaks vs pre-peak months in unadjusted or adjusted multivariable regression (ßadj=-3.85, 95% CI -36.9-29.2, P=0.80). In this final multivariable model (secondary analysis), faster DTP times were significantly associated with transfer from an outside institution (ßadj=-46.44, 95% CI -62.8 to - -30.0, P<0.01) and higher NIHSS (ßadj=-2.15, 95% CI -4.2to - -0.1, P=0.05). CONCLUSIONS: In this multi-center study, there was no delay in EVT among patients treated for intracranial occlusion during the COVID-19 era compared with the pre-COVID era.

Delays in thrombolysis during COVID-19 are associated with worse neurological outcomes: the Society of Vascular and Interventional Neurology Multicenter Collaboration.

INTRODUCTION: We have demonstrated in a multicenter cohort that the COVID-19 pandemic has led to a delay in intravenous thrombolysis (IVT) among stroke patients. Whether this delay contributes to meaningful short-term outcome differences in these patients warranted further exploration. METHODS: We conducted a nested observational cohort study of adult acute ischemic stroke patients receiving IVT from 9 comprehensive stroke centers across 7 U.S states. Patients admitted prior to the COVID-19 pandemic (1/1/2019-02/29/2020) were compared to patients admitted during the early pandemic (3/1/2020-7/31/2020). Multivariable logistic regression was used to estimate the effect of IVT delay on discharge to hospice or death, with treatment delay on admission during COVID-19 included as an interaction term. RESULTS: Of the 676 thrombolysed patients, the median age was 70 (IQR 58-81) years, 313 were female (46.3%), and the median NIHSS was 8 (IQR 4-16). Longer treatment delays were observed during COVID-19 (median 46 vs 38 min, p = 0.01) and were associated with higher in-hospital death/hospice discharge irrespective of admission period (OR per hour 1.08, 95% CI 1.01-1.17, p = 0.03). This effect was strengthened after multivariable adjustment (aOR 1.15, 95% CI 1.07-1.24, p < 0.001). There was no interaction of treatment delay on admission during COVID-19 (pinteraction = 0.65). Every one-hour delay in IVT was also associated with 7% lower odds of being discharged to home or acute inpatient rehabilitation facility (aOR 0.93, 95% CI 0.89-0.97, p < 0.001). CONCLUSION: Treatment delays observed during the COVID-19 pandemic led to greater early mortality and hospice care, with a lower probability of discharge to home/rehabilitation facility. There was no effect modification of treatment delay on admission during the pandemic, indicating that treatment delay at any time contributes similarly to these short-term outcomes.

Largest neurosurgical social media group and its impact on communication and research.

BACKGROUND: The use of social media to communicate and disseminate knowledge has increased exponentially, especially in the field of neurosurgery. 'Neurosurgery cocktail' (NC) was developed by a group of young neurosurgeons as a means of sharing didactic materials and clinical experiences via social media. It connects 35.000 neurosurgeons worldwide on multiple platforms, primarily Facebook and Twitter. Given the rising utilization of social media in neurosurgery, the popularity of NC has also increased since its inception. In this study, the authors surveyed the social media analytics of NC for both Facebook and Twitter. Besides, we reviewed the literature on the use of social media in neurosurgery. METHODS: Facebook and Twitter metrics were extracted through each respective platform's analytics tools from December 2020 (earliest available date for data analysis) through January 2021. A literature search was conducted using PubMed (MEDLINE) and Scopus databases. RESULTS: On Facebook, as of January 2021, the group had a total of 25.590 members (87.6% male), most commonly (29%) between 35 and 44 years of age with over 100 countries were represented. As of January 2021, they had amassed 6457 followers on Twitter. During the last 28 d between December 2020 and January 2021, the account published 65 tweets that garnered a total of 196,900 impressions. Twelve articles were identified in our literature review on the use of social media within the neurosurgical community. CONCLUSIONS: NC is one of the most widely utilized neurosurgical social media resources available. Sharing knowledge has been broadened thanks to the recent social media evolution, and NC has become a leading player in disseminating neurosurgical knowledge.

Collateral Circulation Augmentation and Neuroprotection as Adjuvant to Mechanical Thrombectomy in Acute Ischemic Stroke.

PURPOSE OF THE REVIEW: Mechanical thrombectomy (MT)-mediated endovascular recanalization has dramatically transformed treatment and outcomes after acute ischemic stroke caused by a large vessel occlusion (LVO). Current guidelines recommend MT up to 24 hours from stroke onset in carefully selected patients based on favorable clinical and imaging parameters. Despite optimal patient selection and low complication rates with current recanalization technology, approximately 1 in 2 patients with LVO stroke do not achieve functional independence at 3 months. This ceiling effect of MT efficacy may be explained by ischemic core expansion into the ischemic penumbra before recanalization and neuronal loss occurring after recanalization. Factors affecting the efficacy of MT, or the degree of irreversible injury, include time from symptom onset to recanalization, collateral circulation status, and differences in neuronal vulnerability. The purpose of this brief review is to discuss potential targets for neuroprotection, present and future potential pharmacologic and nonpharmacologic agents, and the data available in the literature. RECENT FINDINGS: In experimental ischemia models, several authors reported that pharmacologic and nonpharmacologic agents are able to slow the progression of ischemic core expansion. However, in the era of unsuccessful recanalization of the occluded artery, several neuroprotective agents that were promising in the preclinical stage failed phase II/III clinical trials. SUMMARY: Providing neuroprotection before and after recanalization of an LVO may play an important role in improving outcomes in the era of MT. Neuroprotection is classically defined as a process that results in the salvage, recovery, or regeneration of neuronal (and other supporting CNS cell) structure or function. The advent of successful recanalization of acute LVO by MT in the majority of patients may spur the growth of effective neuroprotection.

Age and Acute Ischemic Stroke Outcome in North American Patients With COVID-19.

Background Acute ischemic stroke (AIS) in the context of COVID-19 has received considerable attention for its propensity to affect patients of all ages. We aimed to evaluate the effect of age on functional outcome and mortality following an acute ischemic event. Methods and Results A prospectively maintained database from comprehensive stroke centers in Canada and the United States was analyzed for patients with AIS from March 14 to September 30, 2020 who tested positive for SARS-CoV-2. The primary outcome was Modified Rankin Scale score at discharge, and the secondary outcome was mortality. Baseline characteristics, laboratory values, imaging, and thrombectomy workflow process times were assessed. Among all 126 patients with COVID-19 who were diagnosed with AIS, the median age was 63 years (range, 27-94). There were 35 (27.8%) patients with AIS in the aged ≤55 years group, 47 (37.3%) in the aged 56 to 70 group, and 44 (34.9%) in the aged >70 group. Intravenous tissue plasminogen activator and thrombectomy rates were comparable across these groups, (P=0.331 and 0.212, respectively). There was a significantly lower rate of mortality between each group favoring younger age (21.9% versus 45.0% versus 48.8%, P=0.047). After multivariable adjustment for possible confounders, a 1-year increase in age was significantly associated with fewer instances of a favorable outcome of Modified Rankin Scale 0 to 2 (odds ratio [OR], 0.95; 95 CI%, 0.90-0.99; P=0.048) and higher mortality (OR, 1.06; 95 CI%, 1.02-1.10; P=0.007). Conclusions AIS in the context of COVID-19 affects young patients at much greater rates than pre-pandemic controls. Nevertheless, instances of poor functional outcome and mortality are closely tied to increasing age.

Risk of contracting SARS-CoV-2 (COVID-19) from hospital admission and the impact of protection efforts on acute stroke treatment.

BACKGROUND: It is unclear how interventions designed to restrict community and in-hospital exposure to the SARS-CoV-2 (COVID-19) virus influenced stroke care for patients seeking acute treatment. Therefore, we aimed to determine how these COVID-19 interventions impacted acute stroke treatment times and to assess the risk of contracting COVID-19 due to their stay in our medical center. METHODS: Retrospective, single center, two-phase study evaluating hospital and community trends from 12/2019 - 04/2020 compared to the previous year and pre/post (n = 156/93) intervention implementation. Phase I assessed stroke treatment times, delay to hospital arrival, and witnessed stroke volume. Phase II, a post-implementation telephone survey, assessed risk of developing symptoms or testing positive for COVID-19. RESULTS: Stroke volume declined by 29% (p < .05) from April to March compared to the previous year. However, no significant delays in seeking medical care (pre Mdn=112, post Mdn=95, p = .34) was observed. Witnessed stroke volume decreased 11% (p < .001) compared to the pre-implementation group, but no significant delay in IV alteplase (pre Mdn=22 mins; post Mdn=26 mins, p = .08) nor endovascular treatment (pre Mdn=60 mins; post Mdn=80 mins, p = .45) was observed. In Phase II, 63 patients participated, two tested (3%) COVID-19 positive during admission and four (6%) within two weeks of discharge. COVID-19 contraction risk during and after hospitalization remained similar to the general population (RR=1.75, 95%CI: 0.79-3.63). Overall results indicated a marked decrease in stroke volume, no significant delays to either seek or provide acute stroke care were evident, and COVID-19 contraction risk was low. CONCLUSIONS: Seeking acute stroke medical care outweighs the risk of COVID-19 exposure.

New Class of Radially Adjustable Stentrievers for Acute Ischemic Stroke: Primary Results of the Multicenter TIGER Trial.

[Figure: see text].

Duration of symptomatic stroke and successful reperfusion with endovascular thrombectomy for anterior circulation large vessel occlusive stroke.

BACKGROUND: It has been reported that longer time intervals from stroke onset to endovascular therapy are associated with lower rates of successful reperfusion in acute ischemic stroke patients with large vessel occlusion. However, procedural variables and potential mechanisms of this association have not been fully elucidated. METHODS: We performed a secondary analysis of individual patient data from the North American Solitaire Stent Retriever Acute Stroke (NASA) and Trevo Stent-Retriever Acute Stroke (TRACK) registries. We included patients with occlusion of the internal carotid artery or middle cerebral artery (M1 and M2 segments) who were treated by mechanical thrombectomy within 24 hours of last known normal. The primary outcome was reperfusion, defined as a Thrombolysis In Cerebral Infarction (TICI) score ≥2b. The secondary outcome was reperfusion on the first pass. The primary predictor was duration of symptomatic stroke, defined as time from last known normal to time of final pass. Adjusted logistic regression models were utilized to determine associations between variables and outcome. RESULTS: We included 506 patients, of which 401 (79.3%) achieved successful reperfusion (TICI 2b/3). The mean (SD) duration of symptomatic stroke was 6.8 (3.5) hours and in the adjusted logistic regression model the duration of symptomatic stroke was associated with reperfusion (OR 0.90, 95% CI 0.84 to 0.96) and reperfusion on the first pass (OR 0.89, 95% CI 0.83 to 0.95). In that model, the predicted probability of reperfusion was 88% (95% CI 0.83 to 0.92) at 1 hour, 81% (95% CI 0.78 to 0.84) at 6 hours, 70% (95% CI 0.63 to 0.77) at 12 hours, and 42% (95% CI 0.17 to 0.67) at 24 hours (ptrend=0.001). Reperfused patients were significantly younger, more likely to be male, and to have had a balloon guide catheter used during the procedure. CONCLUSION: In a real-world cohort of acute ischemic stroke patients with anterior circulation occlusion treated with endovascular therapy, longer duration of symptomatic stroke is associated with lower rates of successful reperfusion and reperfusion on the first pass.

Education Research: Challenges Faced by Neurology Trainees in a Neuro-Intervention Career Track.

OBJECTIVE: The widespread adoption of endovascular therapy (EVT) for emergent large vessel occlusion has led to increased nationwide demand for neurointerventionalists, heightened interest among neurology residents to pursue neurointervention as a career, and increased importance of neurointervention exposure for all neurologists who care for patients with acute ischemic stroke. Exposure to neurointervention and its career path are not well-defined for neurology trainees. METHODS: The Society for Vascular and Interventional Neurology (SVIN) Education Committee conducted a multicenter electronic survey directed towards neurology residents and vascular neurology (VN), neurocritical care (NCC), and neurointervention fellows in June 2018. A total of 250 programs were invited to participate; 76 trainees completed the survey. RESULTS: Respondents self-identified as 22% postgraduate year (PGY)2, 40% PGY3/4, 30% VN fellows, and 8% neurointervention or NCC fellows. Eighty-seven percent of trainees had more than 2 months exposure to VN during residency, 41% to NCC, and only 3% to neurointervention. Sixty-eight percent of respondents had no exposure to neurointervention during residency. Whereas 72% believed that a background in neurology was good preparation for neurointervention, only 41% agreed that fellowship training pathway in neurointervention is well-structured for neurology residents when compared to other subspecialties. CONCLUSION: In this survey, respondents identified lack of exposure to neurointervention and a well-defined training pathway as obstacles towards pursuing neurointervention as a career. These obstacles must be addressed for the continued development of neurointervention as a subspecialty of neurology.