Three-month and long-term outcomes and their predictors in acute basilar artery occlusion treated with intra-arterial thrombolysis

Locked-in syndrome following elective cervical foraminotomy: a case report

INTRODUCTION

There are no previously reported cases of locked-in syndrome occurring following cervical spinal surgery. We describe a case of locked-in syndrome following an elective cervical foraminotomy and discuss potential etiologies and contributing factors to our patient's presentation.

CASE PRESENTATION

A 54-year-old male with a history of head and neck cancer and prior anterior cervical discectomy and fusion presented with neck pain following a motor vehicle accident. The patient underwent C4-C7 left-sided cervical posterior foraminotomy with no intraoperative complications. On postoperative day 1, the patient suddenly developed rapidly progressing weakness of the extremities and soon became non-verbal. CT angiography and near-infrared spectroscopy confirmed a basilar artery occlusion and left vertebral artery dissection. On MRI, infarcts involving the bilateral pons, left cerebral hemisphere, and left cerebellar infarct were identified.

CONCLUSION

The etiology of locked-in syndrome in our patient remains unclear, but it is likely multifactorial. It is possible that the patient was predisposed to vascular injury from prior radiation therapy to the head and neck. In addition, intraoperative vascular insult may have occurred from vibrational shear stress, in turn leading to a vertebral artery dissection, basilar artery occlusion, and pontine infarct, ultimately resulting in our patient's locked-in state.

IV Thrombolysis in Basilar Artery Occlusion: Outcomes and Comparison With Endovascular Thrombectomy

BACKGROUND AND OBJECTIVES

Recanalization is considered a prerequisite for favorable outcome in basilar artery occlusion (BAO). Intravenous thrombolysis (IVT) has been successfully used for eligible patients with BAO well beyond the 4.5-hour time window but has been largely underrepresented in the best medical management arms in recent randomized controlled trials of recanalization therapy in BAO. We aimed to analyze the outcomes of patients with BAO treated with IVT only and to compare IVT with endovascular thrombectomy (EVT).

METHODS

This observational single-center, retrospective cohort study included consecutive patients with BAO treated with IVT and/or EVT up to 48 hours of symptom onset during 1995-2022. The primary outcome was favorable functional outcome (modified Rankin Scale 0-3) at 3 months collected by a stroke physician by phone. In the first part, we described the outcomes and factors associated with functional outcome in the IVT-only cohort during 1995-2022. In the second part, we used doubly robust inverse probability-weighted regression adjustment models to compare functional outcome of patients treated with IVT vs EVT+/-IVT during 2010-2022.

RESULTS

In the whole cohort of 376 patients with acute BAO treated with recanalization therapy, 245 (65.2%) received only IVT. In the IVT-only cohort, most patients had moderate-to-severe clinical presentation (median NIH Stroke Scale 18) but no extensive early ischemic changes in the posterior circulation on admission. Half of them had onset-to-treatment time over 6 hours. 46.5% of the IVT-treated patients achieved 3-month favorable functional outcome, whereas mortality was 35.9%. sICH occurred in 11.1%. In a multivariable analysis, younger age, milder symptom severity, and less baseline ischemic changes predicted favorable functional outcome. In the 2010-2022 cohort, when compared with patients treated with EVT+/-IVT (n = 121), the IVT-only cohort (n = 122) had higher odds for favorable functional outcome (IVT 58.2% vs EVT 43.0% (aOR 2.82 [95% CI 1.31-6.05]).

DISCUSSION

IVT alone produced outcomes comparable with those in recent trials of endovascular BAO recanalization. Furthermore, in head-to-head comparison in our cohort, the IVT-only approach was more often associated with favorable outcome than EVT+/-IVT. Thus, it should not be overlooked as the first-line recanalization therapy in acute BAO, even in longer time windows.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that tPA is as effective as thrombectomy for basilar artery thrombosis.

Posterior circulation collaterals as predictors of outcome in basilar artery occlusion: a sub-analysis of the BASICS randomized trial

Introduction and purpose

Basilar artery occlusion (BAO) is still one of the most devastating neurological conditions associated with high morbidity and mortality. In the present study, we aimed to assess the role of posterior circulation collaterals as predictors of outcome in the BASICS trial and to compare two grading systems (BATMAN score and PC-CS) in terms of prognostic value.

Methods

We performed a sub-analysis of the BASICS trial. Baseline clinical and imaging variables were analyzed. For the imaging analysis, baseline CT and CTA were analyzed by a central core lab. Only those patients with good or moderate quality of baseline CTA and with confirmed BAO were included. Multivariable binary logistic regression analysis was used to test the independent association of clinical and imaging characteristics with a favorable outcome at 3 months (defined as a modified Rankin Score of ≤3). ROC curve analysis was used to assess and compare accuracy between the two collateral grading systems.

Results

The mean age was 67.0 (±12.5) years, 196 (65.3%) patients were males and the median NIHSS was 21.5 (IQR 11-35). Median NCCT pc-ASPECTS was 10 (IQR10-10) and median collateral scores for BATMAN and PC-CS were 8 (IQR 7-9) and 7 (IQR 6-8) respectively. Collateral scores were associated with favorable outcome at 3 months for both BATMAN and PC-CS but only with a modest accuracy on ROC curve analysis (AUC 0.62, 95% CI [0.55-0.69] and 0.67, 95% CI [0.60-0.74] respectively). Age (OR 0.97, 95% CI [0.95-1.00]), NIHSS (OR 0.91, 95% CI [0.89-0.94]) and collateral score (PC-CS - OR 1.2495% CI [1.02-1.51]) were independently associated with clinical outcome.

Conclusion

The two collateral grading systems presented modest prognostic accuracy. Only the PC-CS was independently associated with a favorable outcome at 3 months.

Development and validation of a novel scoring system for acute ischemic stroke

BACKGROUND

This study aimed to assess the clinical application of the Artery Occlusion Image Score (AOIS), a new metric based on computed tomographic angiography (CTA) that reflects the severity of occlusive changes in the main intracranial arteries.

MATERIALS AND METHODS

Patients diagnosed with acute ischemic stroke (AIS) were divided into three groups: anterior circulation infarcts (ACI group), posterior circulation infarcts (PCI group), and both anterior and posterior circulation infarcts (ACI + PCI group). The sensitivity and specificity of AOIS were evaluated using the Basilar Artery on Computed Tomography Angiography (BATMAN) score, the Clot Burden Score (CBS), and the National Institutes of Health Stroke Scale (NIHSS) as comparators through receiver-operating characteristic (ROC) curve analysis.

RESULTS

The final analysis included 439 consecutive patients. In the ACI group, AOIS demonstrated high sensitivity (86.3%) and specificity (85.0%) and outperformed CBS in predicting patient prognosis. In the PCI group, AOIS also showed high sensitivity (88.9%) and specificity (90.0%) and outperformed BATMAN in predicting patient prognosis. In the ACI + PCI group, AOIS positively correlated with the NIHSS score (Spearman's ρ = 0.602, P < .001). Additionally, the scoring time of AOIS did not significantly differ from CBS and BATMAN.

CONCLUSION

AOIS is a convenient and reliable method for guiding treatment and predicting outcomes in patients with ACI or/and PCI. Furthermore, AOIS is the first CTA-based scoring system that covers both the anterior and posterior circulation, providing a convenient and reliable evaluation for patients with concurrent acute ischemic stroke in both circulations.

Radiology resident competency in detecting basilar artery occlusion: a simulation-based assessment

PURPOSE

Basilar artery strokes are rare but can have characteristic imaging findings that can often be overlooked. This retrospective study aims to assess radiology residents' ability to identify CT imaging findings of basilar artery occlusion in a simulated call environment.

METHODS

The Wisdom in Diagnostic Imaging Emergent/Critical Care Radiology Simulation (WIDI SIM)-a tested and reliable computer-aided emergency imaging simulation-was employed to assess resident readiness for independent radiology call. The simulations include 65 cases of varying complexity, including normal studies, with one case specifically assessing basilar artery stroke. Residents were presented with a single, unique case of basilar artery occlusion in two separate years of testing and were only provided with non-contrast CT images. Residents' free text responses were manually scored by faculty members using a standardized grading rubric, with errors subsequently classified by type.

RESULTS

A total of 454 radiology residents were tested in two separate years on the imaging findings of basilar artery occlusion using the Wisdom in Diagnostic Imaging simulation web-based testing platform. Basilar artery occlusion was consistently underdiagnosed by radiology residents being tested for call readiness irrespective of the numbers of years in training. On average, only 14% of radiology residents were able to correctly identify basilar artery occlusion on non-contrast CT.

CONCLUSIONS

Our findings underscore a potential gap in radiology residency training related to the detection of basilar artery occlusion, highlighting the potential need for increased educational efforts in this area.

Prognostic factors for acute vertebrobasilar artery occlusion-reperfusion: a multicenter retrospective cohort study

BACKGROUND

This study aimed to analyze the long-term prognostic factors in acute vertebrobasilar artery occlusion (VBAO) patients treated with endovascular treatment (EVT).

METHODS

This study was performed using the acute posterior circulation ischemic stroke registry database from 21 stroke centers in 18 cities in China and retrospectively included consecutive patients aged 18 years or older with an acute, symptomatic, radiologically confirmed VBAO who were treated with EVT between December 2015 and December 2018. Favorable clinical outcomes were evaluated by machine-learning methods. A clinical signature was constructed in the training cohort using the least absolute shrinkage and selection operator regression and was validated in the validation cohort.

RESULTS

From 28 potential factors, 7 variables were independent prognostic factors and were included in the model: Modified Thrombolysis in Cerebral Infarction (M) [odds ratio (OR): 2.900; 95% confidence interval [CI]: 1.566-5.370], age (A) (OR, 0.977; 95% CI: 0.961-0.993), National Institutes of Health Stroke Scale (N) (13-27 vs. ≤12: OR, 0.491; 95% CI: 0.275-0.876; ≥28 vs. ≤12: OR, 0.148; 95% CI: 0.076-0.289), atrial fibrillation (A) (OR, 2.383; 95% CI: 1.444-3.933), Glasgow Coma Scale (G) (OR, 2.339; 95% CI: 1.383-3.957), endovascular stent-retriever thrombectomy (E) (stent-retriever vs. aspiration: OR, 0.375; 95% CI: 0.156-0.902), and estimated time of onset of the occlusion to groin puncture (Time) (OR, 0.950; 95% CI: 0.909-0.993) (abbreviated as MANAGE Time). In the internal validation set, this model was well calibrated with good discrimination [C-index (95% CI)=0.790 (0.755-0.826)]. A calculator based on the model can be found online ( http://ody-wong.shinyapps.io/1yearFCO/ ).

CONCLUSION

Our results indicate that optimizing for EVT, along with specific risk stratification, may improve long-term prognosis. However, a larger prospective study is needed to confirm the findings.

What Is the Evidence for Endovascular Thrombectomy in Posterior Circulation Stroke?

Posterior circulation infarcts comprise approximately 25% of ischemic strokes but are less often treated with recanalization therapy and have longer treatment delays compared with anterior circulation strokes. Among posterior circulation strokes, basilar artery occlusion is associated with the most severe deficits and the worst prognosis. Endovascular thrombectomy is a standard of care for patients with anterior circulation large vessel occlusion, but not until recently were the first randomized controlled trials on endovascular thrombectomy in basilar artery occlusion published. Two of the trials were neutral, whereas two others showed better functional outcome after thrombectomy up to 24 hours of symptom onset compared with best medical treatment, which in most cases had low rates of intravenous thrombolysis. According to observational data, thrombectomy seems to be safe also in isolated posterior cerebral artery occlusions and might be an option for selected patients, even if its outcome benefit is yet to be demonstrated.

Functional recovery continues beyond 3 months post-basilar artery thrombectomy: A retrospective cohort study

INTRODUCTION

Untreated basilar artery occlusion (BAO) carries 70% mortality. Guidelines recommend thrombectomy with or without thrombolysis.

AIM

We compared Modified Rankin Scores (mRS) at 3 and 12 months post thrombectomy to determine benefit of long-term follow up.

METHODS

Retrospective, single centre analysis of BAO thrombectomies between 2015 and 2019. Inclusion criteria were symptomatic BAO on CT angiography, absent early ischemic changes, premorbid independence and intervention within 24 h. All received stroke ward care. Results were analysed with simple statistics and binary logistic regression as appropriate.

RESULTS

Of 82 patients: most were male (61%, 50/82) with median age 68 years (IQR 17 years) and median NIHSS 14 (IQR 15). Median door-to-puncture time was 42 min (IQR 72 min). Total deaths were 34.1% (28/82) at 3 months, and 37.8% (31/82) at 12 months. Of 51 patients alive at 12 months: 41% (21/51) had improved mRS, 16% (8/51) had worse mRS and 43% (22/51) had unchanged mRS, compared to 3 months. Improvements to mRS were: one point in 57.1% (14/21), two points in 28.9% (6/21) and three points in 4.8% (1/21). Nursing home admission was avoided in 11.8% (6/51) who improved from mRS4. Increased age was associated with decreased likelihood of reaching the primary outcome OR 0.87, 95% CI 0.76-0.99 (p value = 0.03).

CONCLUSION

Over a quarter of patients improved beyond 3 months. Future studies should adopt long-term follow up as primary outcome.

Machine learning based outcome prediction of large vessel occlusion of the anterior circulation prior to thrombectomy in patients with wake-up stroke

PURPOSE

Outcome prediction of large vessel occlusion of the anterior circulation in patients with wake-up stroke is important to identify patients that will benefit from thrombectomy. Currently, mismatch concepts that require MRI or CT-Perfusion (CTP) are recommended to identify these patients. We evaluated machine learning algorithms in their ability to discriminate between patients with favorable (defined as a modified Rankin Scale (mRS) score of 0-2) and unfavorable (mRS 3-6) outcome and between patients with poor (mRS5-6) and non-poor (mRS 0-4) outcome.

METHODS

Data of 8395 patients that were treated between 2018 and 2020 from the nationwide registry of the German Society for Neuroradiology was retrospectively analyzed. Five models were trained with clinical variables and Alberta Stroke Program Early CT Score (ASPECTS). The model with the highest accuracy was validated with a test dataset with known stroke onset and with a test dataset that consisted only of wake-up strokes.

RESULTS

2419 patients showed poor and 3310 patients showed favorable outcome. The best performing Random Forest model achieved a sensitivity of 0.65, a specificity of 0.81 and an AUC of 0.79 on the test dataset of patients with wake-up stroke in the classification analysis between favorable and unfavorable outcome and a sensitivity of 0.42, a specificity of 0.83 and an AUC of 0.72 in the classification analysis between poor and non-poor outcome.

CONCLUSION

Machine learning algorithms have the potential to aid in the decision making for thrombectomy in patients with wake-up stroke especially in hospitals, where emergency CTP or MRI imaging is not available.

Endovascular treatment for distal basilar artery occlusion stroke

Background

This study aimed to investigate the clinical outcomes of endovascular treatment (EVT) for distal basilar artery occlusion (BAO) and compare them with the outcomes of standard medical treatment (SMT) in daily clinical practice.

Methods

Patients with distal BAO enrolled in the BASILAR study from January 2014 to May 2019 were included. Differences in clinical outcomes were analyzed using Pearson's chi-square test and multivariable logistic regression. Clinical outcomes were evaluated using the modified Rankin Scale (mRS) score at 90 days, the mortality at 90 days, and the occurrence of symptomatic intracranial hemorrhage within 48 h.

Results

Among the 267 patients with distal BAO (222 patients in the EVT group and 45 patients in the SMT group), compared with the SMT group, the EVT group was associated with a favorable outcome (mRS 0–3; 40.1 vs. 15.6%; aOR 5.44; 95% CI, 1.68–17.66; P = 0.005) and decreased mortality (44.6 vs. 71.1%, aOR 0.32, 95% CI, 0.13–0.77; P = 0.012). In the EVT group, multivariable analysis showed that the initial National Institutes of Health Stroke Scale (NIHSS) score and posterior circulation-Alberta Stroke Program Early CT Score (pc-ASPECTS) were associated with favorable functional outcomes and mortality.

Conclusion

Our study suggests that, compared with SMT, EVT is technically feasible and safe for patients with distal BAO.

Mechanical thrombectomy for acute ischemic stroke due to large vessel occlusion in Argentina: An economic analysis

OBJECTIVES

Mechanical thrombectomy (MT) after intravenous thrombolysis (IV-tPA) is an effective and cost-saving treatment for stroke due to large vessel occlusion. However, rates of MT use are low in Argentina. This study was designed to estimate the economic value and the budget impact of incorporating MT after thrombolysis, simulating scenarios from Argentinian compulsory social health insurance (Obras Sociales) and private insurances (Empresas de Medicina Prepaga).

MATERIALS AND METHODS

We adapted a previously published cost-utility and budget-impact (CUA and BIA) model to the Argentinian setting. The CUA was carried out for a lifetime horizon with efficacy inputs from the SWIFT PRIME clinical trial. For seven possible health states, we identified local costs (Argentinian Pesos AR$), utility (QALY), and transition/distribution probabilities (5% discounted rate) and performed deterministic and probabilistic sensitivity analyses. The BIA was based on a six-step approach and a static model for a five-year horizon, and two scenarios (staggered growth and no growth).

RESULTS

Despite higher incremental procedure costs, IV-tPA and MT was dominant over IV-tPA alone (AR$1,049,062 overall savings). Cost-effectiveness remained in the deterministic sensitivity analysis (100% probability of cost-effectiveness). Increased MT procedure volume resulted in savings in years three (0.96%), four (2.6%), and five (4.4%). By year five, 1,280 patients were treated with MT (versus 480) with overall savings of 1.8% (AR$817,244,417).

CONCLUSIONS

MT after IV-tPA is cost-effective in Argentina. Savings offset the incremental hospitalization and long-term costs from the third year onwards. With increased, access the superior efficacy of MT mitigates future disability and comorbidity, reducing overall expenses.

Predictors of unfavorable outcome at 90 days in basilar artery occlusion patients

BACKGROUND

In a previous study, basilar artery occlusion (BAO) was shown to lead to death or disability in 80% of the patients. The treatment for BAO patients in the acute stage includes thrombolysis and intra-arterial thrombectomy, but not all patients benefit from these treatments. Thus, understanding the predictors of outcome before initiating these treatments is of special interest.

AIM

To determine the predictors related to the 90-d clinical outcome in patients with BAO in an Asian population.

METHODS

We performed a retrospective case review of patients admitted to a tertiary stroke center between 2015 and 2019. We used the international classification of diseases-10 criteria to identify cases of posterior circulation stroke. A neurologist reviewed every case, and patients fulfilling the criteria defined in the Basilar Artery International Cooperation Study were included. We then analyzed the patients’ characteristics and factors related to the 90-d outcome.

RESULTS

We identified a total of 99 patients as real BAO cases. Of these patients, 33 (33.3%) had a favorable outcome at 90 d (modified Rankin Scale: 0–3). Moreover, 72 patients received intra-arterial thrombectomy, while 13 patients received intravenous tissue-type plasminogen activator treatment. We observed a favorable outcome in 33.3% of the cases and an unfavorable outcome in 66.7% of the cases. We found that the initial National Institutes of Health Stroke Scale (NIHSS) score and several BAO symptoms, including impaired consciousness, tetraparesis, and pupillary abnormalities, were significantly associated with an unfavorable outcome (P < 0.05), while cerebellar symptoms were associated with a favorable outcome (P < 0.05). In the receiver operating characteristic (ROC) analysis, the areas under the ROC curve of initial NIHSS score, impaired consciousness, tetraparesis, cerebellar symptoms, and pupillary abnormalities were 0.836, 0.644, 0.727, 0.614, and 0.614, respectively. Initial NIHSS score showed a higher AUROC (0.836) compared to BAO symptoms.

CONCLUSION

The most important predictor of an unfavorable outcome was the initial NIHSS score. BAO symptoms, including tetraparesis, impaired consciousness, and pupillary abnormality were also related to an unfavorable outcome.

Posterior Circulation Ischemia in the Endovascular Era

BACKGROUND AND OBJECTIVES

To perform literature review of clinical, radiographic, and anatomical features of posterior circulation ischemia (PCI) and systematic review of the literature on the management of basilar artery occlusion (BAO) and associated outcomes.

METHODS

Review of literature was conducted to identify publications describing the risk factors, etiology, clinical presentation, and imaging for PCI. A systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. PubMed and Ovid MEDLINE were searched from 2009 to 2020 for articles relating to management of BAO. A synthesis was compiled summarizing current evidence on management of BAO.

RESULTS

PCI accounts for 15%-20% of strokes. Risk factors are similar to anterior circulation strokes. Dizziness (47%), unilateral limb weakness (41%), and dysarthria (31%) are the most common presenting symptoms. A noncontrast head CT will identify PCI in 21% of cases; diffusion-weighted MRI or CT perfusion increase sensitivity to 85%. Recent trials have shown endovascular therapy can achieve >80% recanalization of BAO. In select patients, 30%-60% who receive endovascular treatment can achieve favorable outcome vs without. A total of 13% achieve good outcome and there is an 86% mortality rate.

DISCUSSION

PCI can present with waxing and waning symptoms or clinical findings that overlap with stroke mimics and anterior circulation ischemia, making diagnosis more heavily dependent on imaging. Recanalization is an important predictor of improved functional outcome and survival. In this endovascular era, trials of BAO are fraught with deterrents to enrollment. Despite limitations, endovascular treatment has shown improved outcome in select patients.

Prognostic Scores for Large Vessel Occlusion Strokes

PURPOSE OF THE REVIEW

Endovascular thrombectomy (EVT) for large vessel occlusion strokes (LVOS) presents several treatment challenges. We provide a summary of existing tools for patient selection (pre-EVT tools) and for prognostication of long-term outcomes following reperfusion therapy (post-EVT tools).

RECENT FINDINGS

Recently published randomized trials demonstrated superiority of EVT over medical therapy alone for LVOS. Uniform patient selection paradigms based on demographic, clinical, and radiographic variables are not completely standardized, leading to variability in patient selection for EVT for LVOS. Post-EVT, an accurate assessment of long-term prognosis is critical in the decision-making process.

SUMMARY

Prognostic scores can serve as useful adjuncts to facilitate clinical decision-making during early management of patients with ischemic stroke, particularly those with LVOS. The acute management of LVOS comprises rapid clinical assessment, triage, and cerebrovascular imaging, followed by evaluation for candidacy for thrombolysis and EVT. Pre-EVT prognostic tools that accurately predict the likelihood of benefit from EVT may guide reliable, efficient, and cost-effective patient selection. Following EVT, severe stroke deficits and subacute poststroke complications that portend a poor prognosis may warrant invasive therapies. Clinical decisions regarding these treatment options involve careful discussions between providers and patient families, and are also based on prognosis provided by the treating clinician. Reliable post-EVT prognostic tools can facilitate this by providing accurate and objective prognostic information. Several prognostic tools have been developed and validated in the literature, some of which may be applicable in the pre-EVT and post-EVT settings, although clinical utility and application varies. Validation in contemporary datasets as well as implementation and impact studies are needed before these scales can be used to guide clinical decisions for individual patients.

Effects of and prognostic factors affecting endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion

PURPOSE

To investigate the clinical outcome and factors affecting the prognosis of endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion.

MATERIALS AND METHODS

Eighty-three patients with acute vertebrobasilar artery occlusion were treated with endovascular mechanical thrombectomy, and the recanalization rate, clinical outcomes at three months, modified DWI-PC-ASPECTS, and MRA-BATMAN scores were analyzed.

RESULTS

Following acute mechanical thrombectomy, the TICI 2B-3 score was achieved in all patients (100%). At three-month evaluation, 56 (67.5%) patients had good prognosis with the mRS score of 0-2, including 13 (23.2%) patients who had arterial occlusion caused by emboli and 43 (76.8%) who had atherosclerotic stenosis. In analyzing factors affecting the prognosis, a significant difference (P < 0.05) existed between patients with good (mRS 0-2) and poor (mRS 3-6) prognosis in the NIHSS (17.3 vs. 31.2, P = 0.000001), modified DWI-PC-ASPECTS (10.4 vs. 7.8, P = 0.021), and MRA-BATMAN (6.3 vs. 4.6, P = 0.003) scores. Univariate Logistic regression analysis demonstrated NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 to be the risk factors for poor prognosis. Multivariate Logistic regression analysis revealed NIHSS score ≥ 21 as an independent risk factor for poor prognosis.

CONCLUSION

Endovascular mechanical thrombectomy is safe and effective in recanalizing occluded vertebrobasilar artery occlusion, and NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 are the risk factors for poor prognosis.

Mechanical thrombectomy for acute ischemic stroke in the posterior circulation: assessment of efficacy and outcome and identification of prognostic factors

BACKGROUND

Mechanical thrombectomy (MT) is well-established in the treatment of acute ischemic anterior circulation stroke. However, there is no evidence from randomized trials or meta-analyses that MT is safe and effective in the treatment of patients with acute ischemic posterior circulation stroke (PCS).

PURPOSE

To evaluate the clinical and procedural factors associated with recanalization and outcome of patients with PCS treated with MT.

MATERIAL AND METHODS

Forty-three patients with PCS (median age 73 years) who underwent treatment with MT were included. Data including demographics, baseline stroke severity, radiological imaging, procedure and post-procedure complications were documented. Clinical outcome was evaluated using the modified Rankin Scale (mRS). The patients were classified into two groups based on clinical outcome (favorable vs. unfavorable mRS after 90 days).

RESULTS

Median baseline National Institute of Health Stroke Scale (NIHSS) was 17. Twenty patients were eligible for intravenous thrombolysis and received recombinant tissue plasminogen activator before MT. Successful recanalization was observed in 88.4% of patients. After 90 days, favorable outcome (defined as mRS 0-2) was achieved in 26 patients; six patients had an unfavorable outcome (mRs >2). Final mortality rate was 25.5%. Baseline NIHSS, onset to reperfusion time, procedure duration, and successful recanalization had a statistically significant association with outcome. Failed recanalization and occurrence of intracranial hemorrhage were found to be associated with a higher mortality rate.

CONCLUSION

MT is feasible and effective method in treatment of PCS. Baseline NIHSS and onset to reperfusion time were found to be independent predictive factors of clinical outcome.

First-Pass Effect in Basilar Artery Occlusions: Insights From the Endovascular Treatment of Ischemic Stroke Registry

BACKGROUND AND PURPOSE

In the settings of thrombectomy, the first-pass effect (FPE), defined by a complete recanalization after one pass with no rescue therapy, has been shown to be associated with an improved outcome. As this phenomenon has been predominantly described in anterior circulation strokes, we aimed to study the prevalence, outcomes, and predictors of FPE in patients with a basilar artery occlusion.

METHODS

From a prospective multicentric registry, we collected the data of all consecutive basilar artery occlusion patients who underwent thrombectomy and compared the outcomes of patients who achieved FPE and those who did not. We also compared FPE patients with those who achieved a complete recanalization with >1 pass. Finally, a multivariate analysis was performed to determine the predictors of FPE.

RESULTS

Data from 280 patients were analyzed in our study, including 84 of 280 patients (30%) with an atheromatous etiology. An FPE was achieved in 93 patients (33.2%), with a significantly higher proportion of good outcomes (modified Rankin Scale score 0-2 at 3 months) and lower mortality than non-FPE patients. An FPE was also associated with improved outcomes compared with patients who went on to have full recanalization with >1 pass. Contact aspiration as first-line strategy was a strong predictor of FPE, whereas baseline antiplatelets and atheromatous etiology were negative predictors.

CONCLUSIONS

In our study, an FPE was achieved in approximately one-third of patients with a basilar artery occlusion and was associated with improved outcomes. More research is needed to improve devices and techniques to increase the incidence of FPE. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03776877.

Long-term outcome of endovascular therapy for acute basilar artery occlusion

The long-term functional outcome of acute basilar artery occlusion (BAO) patients who received modern endovascular therapy (EVT) is unclear. We sought to assess the long-term functional outcome of BAO patients treated with EVT and determine the prognostic factors associated with favorable outcome. We enrolled consecutive BAO patients who received EVT between December 2012 and December 2018 in this observational study. Baseline characteristics and outcomes were presented. Multivariable logistic regression analysis was performed to identify the prognostic factors associated with long-term outcome. Among the 177 BAO patients included in this study, 80 patients (45.2%) obtained favorable outcome and 97 patients (54.8%) had unfavorable outcome at long-term follow-up with a median observation time of 12 months (interquartile range, 3-19). A total of 67 patients (37.9%) died. National Institutes of Health Stroke Scale (NIHSS), posterior circulation Alberta Stroke Program Early Computed Tomography Score (pc-ASPECTS), time from stroke onset to recanalization, and recanalization condition were identified as independent predictors for long-term outcome. Over 40% of BAO patients who were treated with modern EVT achieved favorable outcome at long-term follow-up. NIHSS, pc-ASPECTS, time from stroke onset to recanalization, and recanalization condition were identified as independent prognostic factors of long-term outcome.

Comatose With Basilar Artery Occlusion: Still Odds of Favorable Outcome With Recanalization Therapy

Background: Around 30–60% of patients with basilar artery occlusion (BAO) present with coma, which is often considered as a hallmark of poor prognosis.

Aim: To examine factors that will help predict outcomes in patients with BAO comatose on admission.

Methods: A total of 312 patients with angiography-proven BAO were analyzed. Comas were assessed as Glasgow Coma Scale (GCS) of ≤8 or impaired level of consciousness ascertained in the medical records. Outcomes were evaluated with the modified Rankin Scale (mRS) over a phone call at 3 months. In our study, 53 patients were excluded due to inadequate data on the level of consciousness.

Results: In total, 103/259 (39.8%) of BAO patients were comatose on admission. Factors associated with acute coma were higher age, coronary artery disease, convulsions, extent of early ischemia by posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) < 8, absence of patent posterior collateral vasculature, and occlusion over multiple segments of BA. A total of 21/103 (20.4%) of comatose patients had a favorable outcome (mRS 0–3), and 12/103 (11.7%) had a good outcome (mRS 0–2). Factors associated with a favorable outcome in comatose BAO patients were younger age (p = 0.010), less extensive baseline ischemia (p = 0.027), recanalization (p = 0.013), and avoiding symptomatic intracranial hemorrhage (sICH) (p = 0.038). Factors associated with the poorest outcome or death (mRS 5–6) were older age (p = 0.001), diabetes (p = 0.022), atrial fibrillation (p = 0.016), lower median GCS [4 (IQR 3.6) vs. 6 (5–8); p = 0.006], pc-ASPECTS < 8 (p = 0.003), unsuccessful recanalization (p = 0.006), and sICH (p = 0.010). Futile recanalization (mRS 4–6) was significantly more common in comatose patients (49.4 vs. 18.5%, p < 0.001).

Conclusions: One in five BAO patients with acute coma had a favorable outcome. Older patients with cardiovascular comorbidities and already existing ischemic lesions before reperfusion therapies tended to have a poor prognosis, especially if no recanalization is achieved and sICH occurred.

Outcomes and long-term mortality after basilar artery occlusion-A cohort with up to 20 years' follow-up

BACKGROUND

The data on long-term outcome after basilar artery occlusion (BAO) are scarce. Little is known about BAO survivors´ outcome over decades.

AIM

We set out to investigate long-term survival and causes of death in BAO patients with up to two decades of follow-up. We also evaluated differences in outcome trends.

METHODS

Two hundred and seven BAO patients treated with intravenous thrombolysis (IVT) at the Department of Neurology, Helsinki University Hospital, between 1995 and 2016, were analyzed. Short-term outcome was assessed by modified Rankin Scale (mRS) at 3 months. Long-term cumulative survival rate was analyzed using Kaplan-Meier analysis. Factors associated with mortality were analyzed with Cox regression.

RESULTS

Moderate outcome (mRS 0-3) was achieved in 41.1% and good outcome (mRS 0-2) in 30.4% of patients at 3 months. Three-month mortality was 39.6%, of which 89% died within the first month. The median follow-up time in 3-month survivors was 8.9 years (maximum 21.8 years). Total mortality during follow-up was 52.2%. Cumulative mortality rate was 25.7%. Older age, coronary artery disease and more extensive ischemic changes on admission brain imaging were independently associated with long-term mortality. After the acute phase, the rate of other vascular causes of death increased in relation to stroke.

CONCLUSIONS

The described evolution of a large, single-center BAO cohort shows a trend towards a higher rate of good and/or moderate outcome during later years in IVT-treated patients. Survivors showed relative longevity, and the rate of cardiac and other vascular causes of death increased in relation to stroke sequelae over the long term.

Postcontrast CT to Estimate Arteriosclerotic Stenosis at the Site of Occlusion before Emergency Endovascular Treatment for Vertebral-Basilar Artery Occlusion

Objective

Thrombectomy may be an effective therapy for vertebrobasilar artery (VBA) occlusion in addition to carotid or middle cerebral artery occlusion. Underlying arterial stenosis can be a cause of failure in thrombectomy; however, it is difficult to identify candidates with VBA occlusion before thrombectomy. The purpose of our study was to investigate whether postcontrast computed tomography (pcCT) is useful for identifying candidates with VBA occlusion for thrombectomy.

Methods

In this retrospective study, we included patients who 1) were admitted to our institution between January 1, 2013, and July 1, 2019; 2) underwent pcCT; and 3) underwent emergency endovascular therapy for VBA occlusion. We defined no opacification of the top of the basilar artery (BA) in reconstructed coronal images of pcCT scans as distal BA occlusion and opacification of the top of the BA as distal BA open. We assessed the presence of underlying arterial stenosis at the site of occlusion according to angiographic findings during endovascular procedures. We also evaluated the relationship between the distal BA findings and the presence of underlying arterial stenosis.

Results

Thirty-two patients met our inclusion criteria and were analyzed. Among 19 patients with distal BA occlusion, none (0%) had ischemic stroke with underlying arterial stenosis. Among 13 patients with distal BA open, 4 (31%) were diagnosed with ischemic stroke without underlying arterial stenosis and 9 (69%) with underlying arterial stenosis (p <0.001).

Conclusion

Distal basilar-artery findings in reconstructed coronal postcontrast CT images were useful for identifying candidates with VBA occlusion for thrombectomy.

Predicting outcomes after acute reperfusion therapy for basilar artery occlusion

BACKGROUND AND PURPOSE

Basilar artery occlusion (BAO) leads to high rates of morbidity and mortality, despite successful recanalization. The discordance between flow restoration and long-term functional status clouds clinical decision-making regarding further aggressive care. We sought to develop and validate a practical, prognostic tool for the prediction of 3-month favorable outcome after acute reperfusion therapy for BAO.

METHODS

This retrospective, multicenter, observational study was conducted at four high-volume stroke centers in the USA and Europe. Multivariate regression analysis was performed to identify predictors of favorable outcome (90-day modified Rankin scale scores 0-2) and derive a clinically applicable prognostic model (the Pittsburgh Outcomes after Stroke Thrombectomy-Vertebrobasilar (POST-VB) score). The POST-VB score was evaluated and internally validated with regard to calibration and discriminatory ability. External validity was assessed in patient cohorts at three separate centers.

RESULTS

In the derivation cohort of 59 patients, independent predictors of favorable outcome included smaller brainstem infarct volume on post-procedure magnetic resonance imaging (P < 0.01) and younger age (P = 0.01). POST-VB score was calculated as: age + (10 × brainstem infarct volume). POST-VB score demonstrated excellent discriminatory ability [area under the receiver-operating characteristic curve (AUC) = 0.91] and adequate calibration (P = 0.88) in the derivation cohort (Center A). It performed equally well across the three external validation cohorts (Center B, AUC = 0.89; Center C, AUC = 0.78; Center D, AUC = 0.80). Overall, a POST-VB score < 49 was associated with an 88% likelihood of favorable outcome, as compared to 4% with a score ≥ 125.

CONCLUSIONS

The POST-VB score effectively predicts 3-month functional outcome following acute reperfusion therapy for BAO and may aid in guiding post-procedural care.

Basilar artery thrombectomy: assessment of outcome and identification of prognostic factors

Mechanical thrombectomy (MT) has been demonstrated as an effective treatment for acute ischemic stroke (AIS), thanks to large vessel occlusion (LVO), especially in case of anterior cerebral artery with many randomized clinical trials (RCTs) every year. On the other hand, there is a limited number of basilar artery occlusion (BAO)-related studies which have been conducted. The fact prompts our range of case studies, which furnish BAO understanding with our experience, results and some prognosis factors of MT. This retrospective and single-center study was conducted on 22 patients who were diagnosed with BAO and underwent the treatment of MT from October 2012 to January 2018. Clinical feature such as radiological imaging, procedure complications, and intracranial hemorrhage were all documented and evaluated. All the studies' results based on performance using modified Rankin scale score (mRS) and mortality at 90 days. The results from these BAO patients study indicated that the posterior circulation Acute Stroke Prognosis Early CT Score (pcASPECTS) recorded before the intervention was 7.7 ± 1.6, while the admission National Institutes of Health Stroke Scale (NIHSS) was 17.5 ± 5.4. 15/22 cases achieved successful recanalization (TICI, Thrombolysis in Cerebral Infarction scale, of 2b-3), accounting for 68.2%. The results highlighted 50% of the favorable outcome (mRS 0-2) occupying 11 out of 22 patients in total and the overall mortality was 36.4%. The intracranial hemorrhagic complication was detected in three cases (13.6%). Placing in juxtaposition the poor-outcome group and the favorable-outcome group, we could witness statistically significant difference (P < 0.05) suggesting both good baseline image (pc-ASPECTS ≥ 7) and recanalization (TICI 2b-3) were two good prognosis factors. Our case series showed that MT would be an effective and feasible treatment for BAO. The pre-procedural pcASPECTS ≥ 7 and post-procedural good recanalization (TICI 2b-3) were two important prognosis factors for predicting good clinical outcome.

Long-term mortality, disability and stroke recurrence in patients with basilar artery occlusion

BACKGROUND AND PURPOSE

The long-term outcomes and stroke recurrence after basilar artery occlusion (BAO) are largely unknown. We aimed to assess these variables in a comparatively large series of consecutive patients.

METHODS

Adults with acute BAO were retrospectively identified from 1976 to 2011. Post-discharge records were reviewed to assess for stroke recurrences, mortality and disability. Exploratory analysis of survival was carried out using Kaplan-Meier and log-rank tests. Factors associated with survival time were determined using Cox models.

RESULTS

A total of 86 patients (34% female, median age 72 [interquartile range (IQR), 60-79] years) with a median National Institutes of Health Stroke Scale score of 11 (IQR, 6-27) were included. Twenty-nine patients (34%) died during the initial hospitalization. Median modified Rankin Scale (mRS) score at discharge among survivors was 4 (IQR, 2.5-5.5). At 1 and 5 years, 70% of survivors ad a mRS ≤3. Seventeen patients had recurrent strokes during the hospitalization and 12 patients had 19 recurrent strokes after discharge. The median survival time was 52 days (IQR, 6-1846). Older age per decade on admission [adjusted hazard ratios (aHR), 1.32; 95% confidence interval (CI), 1.05-1.66, P = 0.02] and a higher mRS at discharge (aHR, 4.48; 95% CI, 2.72-7.39, P < 0.0001) were associated with mortality. Patients who were not treated with any reperfusion therapy had a trend towards reduced mortality (aHR, 0.39; 95% CI, 0.14-1.08, P = 0.07).

CONCLUSIONS

Survivors from BAO had severe short-term functional disability. Most deaths and stroke recurrences occurred within the first year following the initial event. The risk of death was higher in older and more disabled survivors. However, favorable long-term recovery was possible.

Stroke mechanisms and outcomes of isolated symptomatic basilar artery stenosis

Background

While diffuse atherosclerotic disease affecting the posterior circulation has been described extensively, the prevalence, natural history and angiographic characteristics of isolated symptomatic basilar artery stenosis (ISBAS) remain unknown.

Methods

We reviewed our prospective institutional database to identify patients with ≥50% symptomatic basilar artery (BA) stenosis without significant atherosclerotic burden in the vertebral or posterior cerebral arteries. Stroke mechanism, collateral circulation, and degree and length of stenosis were analysed. The primary outcome was time from index event to new transient ischaemic attack (TIA), acute ischaemic stroke (AIS) or death. Other outcome variables included modified Rankin Scale (mRS) score on discharge and last follow-up.

Results

Of 6369 patients with AIS/TIA, 91 (1.43%) had ISBAS. Seventy-three (80.2%) patients presented with AIS and 18 (19.8%) with TIA. Twenty-nine (31.9%) were women and the median age was 66.8±13.6 years. The mean follow-up time was 2.7 years. The most common stroke mechanism was artery-to-artery thromboembolism (45.2%), followed by perforator occlusion (28.7%) and flow-dependent/hypoperfusion (15.1%). The percentage of stenosis was lower in patients who had favourable outcome compared with those with mRS 3-6 on discharge (78.3±14.3 vs 86.9±14.5, p=0.007). Kaplan-Meier curves showed higher recurrence/death rates in patients with ≥80% stenosis, mid-basilar location and poor collateral circulation. Approximately 13% of patients with ISBAS presented with complete BA occlusion.

Conclusion

ISBAS is an uncommon (1.43%) cause of TIA and AIS. Men in their 60s are mostly affected, and artery-to-artery embolism is the most common stroke mechanism. Mid-basilar location, ≥80% stenosis and poor collateral circulation are important factors associated with worse prognosis.

Mechanical thrombectomy for basilar artery occlusion: efficacy, outcomes, and futile recanalization in comparison with the anterior circulation

BACKGROUND

Performing mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO) is currently not evidence-based.

OBJECTIVE

To compare patients' outcome, relative merits of achieving recanalization, and predictors of futile recanalization (FR) between BAO and anterior circulation large vessel occlusion (ACLVO) MT.

METHODS

In the multicenter BEYOND-SWIFT registry (NCT03496064), univariate and multivariate (displayed as adjusted Odds Ratios, aOR and 95% confidence intervals, 95%-CI) outcome comparisons between BAO (N=165) and ACLVO (N=1574) were performed. The primary outcome was favorable outcome at 90 days (modified Rankin Scale, mRS 0-2). Secondary outcome included mortality, symptomatic intracranial hemorrhage (sICH) and FR. The relative merits of achieving successful recanalization between ACLVO and BAO were evaluated with interaction terms.

RESULTS

MT in BAO was more often technically effective and equally safe in regards to mortality and sICH when compared to ACLVO. When adjusting for baseline differences, there was no significant difference between BAO vs ACLVO regarding rates of favorable outcome (aOR 0.986, 95%-CI 0.553 - 1.758). However, BAO were associated with increased rates of FR (aOR 2.146, 95%-CI 1.267 - 3.633). Predictors for FR were age, stroke severity, maneuver count and intracranial stenting. No significant heterogeneity on the relative merits of achieving successful recanalization on several outcome parameters were observed when comparing BAO and ACLVO.

CONCLUSIONS

In selected patients, similar outcomes can be achieved in BAO and ACLVO patients treated with MT. Randomized controlled trials comparing patient selection and interventional strategies seem warranted to avoid FR.

TRIAL REGISTRATION NUMBER

NCT03496064.

Posterior circulation ischemic stroke-a review part II: imaging and acute treatment

Posterior circulation strokes affect the vertebrobasilar arterial system, account for about 20-25% of all ischemic strokes, and are a significant cause of patient disability and mortality. Diagnosis can be challenging; clinical presentation and common pitfalls facing posterior circulation stroke have been discussed elsewhere. In the first part of the review, we focus on the imaging, discussing the information that can be gathered through a correct selection and interpretation of different possible studies helping to achieve an early diagnosis and to select the best medical treatment. In the second part of the review, we will discuss the best therapeutic treatments available at the moment for posterior circulation ischemia.

Intravenous Thrombolysis in Posterior Circulation Stroke

Background: Intravenous thrombolysis (IVT) is a standard treatment for both anterior circulation ischemic stroke (ACIS) and posterior circulation ischemic stroke (PCIS). PCIS is a clinical syndrome associated with ischemia-related changes in the territory of the posterior circulation arteries. Embolism is the most common stroke mechanism in posterior circulation. PCIS represents 12–19% of all IVT-treated strokes.

Methods and Results: We searched the PubMed database for assessments of intracerebral hemorrhage (ICH) and clinical outcome in PCIS patients treated with IVT. ICH occurs in 0–6.9% of posterior ischemic stroke depending on the definition of symptomatic ICH, and any ICH in 17–23.4% of posterior ischemic stroke. For patients with PCIS, 38–49% have a favorable outcome (mRS 0–1) after IVT. Better clinical outcomes occur more often in patients with PCIS than in those with ACIS. The mortality rate among PCIS patients treated with IVT ranges from 9 to 19%; it does not differ significantly between PCIS and ACIS.

Conclusions: Up to date, no data about PCIS and IVT are available from RTCs. Based on limited results from retrospective clinical studies and case series, IVT is safer for use in PCIS than in ACIS. Patients with brainstem ischemia, vertebral artery occlusion, and absence of basilar or posterior cerebral artery occlusion could be considered for treatment with IVT even in borderline cases. Time to IVT in PCIS seems to be a less crucial factor than in ACIS. IVT for PCIS may be beneficial even after 4.5 h from symptom onset.

Baseline Troponin T level in stroke and its association with stress cardiomyopathy

BACKGROUND

Differential diagnosis of elevated high sensitive Troponin T (hsTnT) in acute ischemic stroke includes myocardial infarction (MI) and neurogenic stunned myocardium (NSM). The aim of this study was to identify factors associated with baseline hsTnT levels and MI or NSM in acute ischemic stroke.

METHODS

We studied 204 consecutive patients of the prospective acquired Bern Stroke Database with acute ischemic stroke diagnosed by brain MR. All patient histories and cardiac examinations were reviewed retrospectively. Volumetry of lesions on diffusion and perfusion weighted brain imaging (circular singular value decomposition, Tmax >6sec) was performed. Voxel based analysis was performed to identify brain areas associated with hsTnT elevation. Linear regression analysis was used to identify predictors of baseline hsTnT levels and myocardial infarction.

RESULTS

Elevated hsTnT was observed in 58 of the 204 patients (28.4%). The mean age was 68.3 years in the normal hsTnT group and 69.7 years in the elevated hsTnT group. Creatinine (p<0.001, OR 6.735, 95% CI 58.734-107.423), baseline NIHSS score (p = 0.029, OR 2.207, 95% CI 0.675-12.096), ST segment depression (p = 0.025, OR 2.259, 95% CI 2.419-35.838), and negative T waves in baseline ECG (p = 0.002, OR 3.209, 95% CI 13.007-54.564) were associated with hsTnT elevation, while infarct location and size were not. Coronary angiography was performed in 30 of the 204 patients (14.7%) and myocardial infarction was diagnosed in 7 of them (23.3%). Predictive factors for myocardial infarction could not be identified.

CONCLUSION

Elevated baseline baseline hsTnT was associated with NIHSS, creatinine, ST segment depression and inverted T waves, but not with stroke location or size. None of the factors was helpful to differentiate MI and NSM. Therefore, ancillary investigations such as coronary angiography, cardiac MRI or both may be needed to solve the differential diagnosis.

Predictors of Good Outcome After Endovascular Treatment for Patients with Vertebrobasilar Artery Occlusion due to Intracranial Atherosclerotic Stenosis

PURPOSE

To investigate the predictors for good outcome of endovascular therapy (EVT) for patients with acute vertebrobasilar artery occlusion (VBAO) due to intracranial atherosclerosis stenosis (ICAS).

METHODS

From April 2012 to February 2018, patients with VBAO due to ICAS who received EVT were retrospectively analyzed. ICAS was defined as fixed stenosis of >70%, or a degree of fixed stenosis >50% in addition to either perfusion impairment or evidence to re-occlusion. Good outcome was defined as mRS≤2 at 90 days. Both logistic regression and receiver operating characteristic curve (ROC) analyses were performed to explore the predictors.

RESULTS

Among 103 patients enrolled in the analysis, 40.8% achieved good outcome. Prior antiplatelet therapy (OR, 7.301; 95% CI, 1.761-30.265; P=0.006), EVT+IVT (OR, 7.343; 95% CI, 1.621-33.263; P=0.010 ), the pc-ASPECT on DWI (OR, 1.705; 95% CI, 1.127-2.580; P=0.012), BATMAN (OR, 1.395; 95% CI, 1.005-1.937; P=0047), general anesthesia (OR, 0.081; 95% CI, 0.010-0.633; P=0.017), onset-to-recanalization time (≤542min vs. >542min) (OR, 0.194; 95% CI, 0.057-0.661; P=0.009) and the initial NIHSS (OR, 0.882; 95% CI, 0.820-0.949; P=0.001) were significantly associated with good outcome in logistic regression. Based on ROC analyses, initial NIHSS score (area under the curve [AUC]= 0.816, p <0.001; cutoff,19.5; sensitivity, 78.7%; specificity, 72.5%) was significant predictors of good outcome.

CONCLUSIONS

For patients with VBAO due to ICAS, prior antiplatelet therapy, EVT+IVT, local anesthesia, short onset-to-recanalization time, a low initial NIHSS, a high pc-ASPECT and BATMAN might be helpful to predict the good outcome at 90 days after EVT.

Association of anemia and hemoglobin decrease during acute stroke treatment with infarct growth and clinical outcome

Background and purpose

Anemia is associated with worse outcome in stroke, but the impact of anemia with intravenous thrombolysis or endovascular therapy has hardly been delineated. The aim of this study was to analyze the role of anemia on infarct evolution and outcome after acute stroke treatment.

Methods

1158 patients from Bern and 321 from Los Angeles were included. Baseline data and 3 months outcome assessed with the modified Rankin Scale were recorded prospectively. Baseline DWI lesion volumes were measured in 345 patients and both baseline and final infarct volumes in 180 patients using CT or MRI. Multivariable and linear regression analysis were used to determine predictors of outcome and infarct growth.

Results

712 patients underwent endovascular treatment and 446 intravenous thrombolysis. Lower hemoglobin at baseline, at 24h, and nadir until day 5 predicted poor outcome (OR 1.150–1.279) and higher mortality (OR 1.131–1.237) independently of treatment. Decrease of hemoglobin after hospital arrival, mainly induced by hemodilution, predicted poor outcome and had a linear association with final infarct volumes and the amount and velocity of infarct growth. Infarcts of patients with newly observed anemia were twice as large as infarcts with normal hemoglobin levels.

Conclusion

Anemia at hospital admission and any hemoglobin decrease during acute stroke treatment affect outcome negatively, probably by enlarging and accelerating infarct growth. Our results indicate that hemodilution has an adverse effect on penumbral evolution. Whether hemoglobin decrease in acute stroke could be avoided and whether this would improve outcome would need to be studied prospectively.

Relating Acute Lesion Loads to Chronic Outcome in Ischemic Stroke-An Exploratory Comparison of Mismatch Patterns and Predictive Modeling

Objectives: To investigate the relationship between imaging features derived from lesion loads and 3 month clinical assessments in ischemic stroke patients. To support clinically implementable predictive modeling with information from lesion-load features. Methods: A retrospective cohort of ischemic stroke patients was studied. The dataset was dichotomized based on revascularization treatment outcome (TICI score). Three lesion delineations were derived from magnetic resonance imaging in each group: two clinically implementable (threshold based and fully automatic prediction) and 90-day follow-up as final groundtruth. Lesion load imaging features were created through overlay of the lesion delineations on a histological brain atlas, and were correlated with the clinical assessment (NIHSS). Significance of the correlations was assessed by constructing confidence intervals using bootstrap sampling. Results: Overall, high correlations between lesion loads and clinical score were observed (up to 0.859). Delineations derived from acute imaging yielded on average somewhat lower correlations than delineations derived from 90-day follow-up imaging. Correlations suggest that both total lesion volume and corticospinal tract lesion load are associated with functional outcome, and in addition highlight other potential areas associated with poor clinical outcome, including the primary somatosensory cortex BA3a. Fully automatic prediction was comparable to ADC threshold-based delineation on the successfully treated cohort and superior to the Tmax threshold-based delineation in the unsuccessfully treated cohort. Conclusions: The confirmation of established predictors for stroke outcome (e.g., corticospinal tract integrity and total lesion volume) gives support to the proposed methodology-relating acute lesion loads to 3 month outcome assessments by way of correlation. Furthermore, the preliminary results indicate an association of further brain regions and structures with three month NIHSS outcome assessments. Hence, prediction models might observe an increased accuracy when incorporating regional (instead of global) lesion loads. Also, the results lend support to the clinical utilization of the automatically predicted volumes from FASTER, rather than the simpler DWI and PWI lesion delineations.

Diagnosis and Management of Acute Ischemic Stroke

Acute ischemic stroke (AIS) is among the leading causes of death and long-term disability. Intravenous tissue plasminogen activator has been the mainstay of acute therapy. Recently, several prospective randomized trials documented the value of endovascular revascularization in selected patients with large-vessel occlusion within the anterior circulation. This finding has led to a paradigm shift in the management of AIS, including wide adoption of noninvasive neuroimaging to assess vessel patency and tissue viability, with the supplemental and independent use of intravenous tissue plasminogen activator to improve clinical outcomes. In this article, we review the landmark studies on management of AIS and the current position on the diagnosis and management of AIS. The review also highlights the importance of early stabilization and prompt initiation of therapeutic interventions before, during, and after the diagnosis of AIS within and outside of the hospital.

Characteristics associated with outcome in patients with first-ever posterior fossa stroke

BACKGROUND AND PURPOSE

Factors such as infarct volume, infarct location and symptom severity can considerably influence long-term outcome in posterior fossa strokes. The decision about therapy can sometimes be complicated by discrepancies between infarct volume and clinical severity. We aimed to evaluate imaging and clinical parameters possibly influencing long-term outcome in patients with first-ever posterior fossa stroke.

METHODS

Imaging was performed on a 3-T magnetic resonance imaging scanner. Sixty-one of 1795 patients from the observational 1000Plus and LOBI studies (NCT00715533 and NCT02077582, clinicaltrials.org) were enrolled, meeting the inclusion criteria of first-ever posterior fossa stroke and magnetic resonance imaging examination within 24 h after symptom onset. Infarcts were classified as belonging to a proximal, middle or distal territory location in the posterior fossa. Good outcome was defined as a modified Rankin scale score of ≤1 at 3 months.

RESULTS

The largest lesion volumes on diffusion-weighted imaging on day 0 and fluid attenuation inversion recovery (FLAIR) on day 6 were found in the middle territory location with a median volume of 0.4 mL on diffusion-weighted imaging and 1.0 mL on FLAIR on day 6 versus 0.1/0.3 mL in the proximal and 0.1/0.1 mL in the distal territory location of the posterior fossa, respectively. Parameters associated with poor outcome were older age (P = 0.005), higher National Institutes of Health Stroke Scale score on admission/discharge (P = 0.016; P = 0.001), larger lesion volumes on FLAIR on day 6 (P = 0.013) and dysphagia (P = 0.02). There was no significant association between infarct location and modified Rankin scale score on day 90.

CONCLUSION

Infarct volume and clinical severity, but not infarct location, were the main contributors to poor long-term outcome in first-ever posterior fossa strokes.

Impact of stroke mechanism in acute basilar occlusion with reperfusion therapy

Objective

We aimed to evaluate the impact of underlying mechanism of basilar artery (BA) occlusion on the outcomes after endovascular therapy (EVT) for reperfusion and the outcome factors associated with each mechanism, and to identify radiologic parameters enabling to distinguish the underlying mechanism.

Methods

From a registry database, 194 consecutive patients with acute BA occlusion who underwent EVT were analyzed. Stroke mechanism, classified into in situ atherosclerotic thrombosis (ISAT) and embolism, clot sign location profiles in pre‐angiography magnetic resonance image (MRI), parameters of angiography and EVT, and reperfusion were assessed. Poor outcome was defined as a modified Rankin‐Scale score at 90 days of 3–6.

Results

The mean age was 68.8±11.8 years (range 21–92 years) and seventy‐eight (40.2%) were female patients. 102 (52.6%) patients were classified into an embolism mechanism and 92 (47.4%) into an ISAT mechanism. Overall, ISAT mechanism compared with embolism was significantly associated with poor outcomes (P = 0.002), along with the NIHSS scores, reperfusion status, and collateral status. In the embolism group, reperfusion (P = 0.001), NIHSS scores (P < 0.001), and onset‐to‐treatment time (P = 0.030) were significant outcome factors. However, in the ISAT group, baseline collateral status (P = 0.001) and NIHSS scores (P < 0.001) were significant outcome factors. A clot sign at the distal BA segment on pre‐angiography MRI was strongly associated with embolism mechanism (P < 0.001).

Interpretation

Stroke mechanism has a major influence on outcomes, and outcome predictors differ according to the underlying mechanism in acute BA occlusion with EVT. Clot sign profile on pre‐angiography MRI might be useful to determine the underlying mechanism.

Focal T2 and FLAIR hyperintensities within the infarcted area: A suitable marker for patient selection for treatment?

Background and purpose

Some authors use FLAIR imaging to select patients for stroke treatment. However, the effect of hyperintensity on FLAIR images on outcome and bleeding has been addressed in only few studies with conflicting results.

Methods

466 patients with anterior circulation strokes were included in this study. They all were examined with MRI before intravenous or endovascular treatment. Baseline data and 3 months outcome were recorded prospectively. Focal T2 and FLAIR hyperintensities within the ischemic lesion were evaluated by two raters, and the PROACT II classification was applied to assess bleeding complications on follow up imaging. Logistic regression analysis was used to determine predictors of bleeding complications and outcome and to analyze the influence of T2 or FLAIR hyperintensity on outcome.

Results

Focal hyperintensities were found in 142 of 307 (46.3%) patients with T2 weighted imaging and in 89 of 159 (56%) patients with FLAIR imaging. Hyperintensity in the basal ganglia, especially in the lentiform nucleus, on T2 weighted imaging was the only independent predictor of any bleeding after reperfusion treatment (33.8% in patients with vs. 18.2% in those without; p = 0.003) and there was a non-significant trend for more bleedings in patients with FLAIR hyperintensity within the basal ganglia (p = 0.069). However, there was no association of hyperintensity on T2 weighted or FLAIR images and symptomatic bleeding or worse outcome.

Conclusion

Our results question the assumption that T2 or FLAIR hyperintensities within the ischemic lesion should be used to exclude patients from reperfusion therapy, especially not from endovascular treatment.

Fully automated stroke tissue estimation using random forest classifiers (FASTER)

Several clinical trials have recently proven the efficacy of mechanical thrombectomy for treating ischemic stroke, within a six-hour window for therapy. To move beyond treatment windows and toward personalized risk assessment, it is essential to accurately identify the extent of tissue-at-risk ("penumbra"). We introduce a fully automated method to estimate the penumbra volume using multimodal MRI (diffusion-weighted imaging, a T2w- and T1w contrast-enhanced sequence, and dynamic susceptibility contrast perfusion MRI). The method estimates tissue-at-risk by predicting tissue damage in the case of both persistent occlusion and of complete recanalization. When applied to 19 test cases with a thrombolysis in cerebral infarction grading of 1-2a, mean overestimation of final lesion volume was 30 ml, compared with 121 ml for manually corrected thresholding. Predicted tissue-at-risk volume was positively correlated with final lesion volume ( p < 0.05). We conclude that prediction of tissue damage in the event of either persistent occlusion or immediate and complete recanalization, from spatial features derived from MRI, provides a substantial improvement beyond predefined thresholds. It may serve as an alternative method for identifying tissue-at-risk that may aid in treatment selection in ischemic stroke.

Utility of digital subtraction angiography-based collateral evaluation in medically treated acute symptomatic basilar artery stenosis

BACKGROUND AND PURPOSE

Although a stroke from atherosclerosis in the basilar artery (BA) often presents with mild initial stroke severity, it has heterogeneous clinical courses. We investigated the efficacy of digital subtraction angiography (DSA)-based collateral perfusion evaluation in association with long-term outcomes of medically treated symptomatic basilar artery stenosis.

METHODS

From a registry database of all consecutive patients with stroke, we included 98 medically treated patients (due to mild initial stroke severity) [National Institute of Health Stroke Scale (NIHSS) scores ≤ 4; symptomatic basilar artery stenosis, 70-99%] with available initial diagnostic DSA. Basilar collateral scoring was performed via the DSA, using a modified version of the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology grading system in both the superior cerebellar artery and anterior/posterior-inferior cerebellar artery territories (score 0-8). The outcomes were designated as the 90-day modified Rankin Scale (mRS90) score (poor, 3-6). Student's t-test, chi-square test and logistic regression analyses were used to identify factors associated with a poor outcome.

RESULTS

The median initial NIHSS score was 2 [interquartile range (IQR), 0-3], median posterior circulation Alberta Stroke Program Early CT Score was 8 (IQR, 7-10), median collateral score was 7 (IQR, 7-8) and 20 (20.4%) had poor mRS90 scores. In multivariate analysis, poorer collateral scores (P = 0.003), higher NIHSS scores (P = 0.005) and lower posterior circulation Alberta Stroke Program Early CT Score (P = 0.017) were independently associated with a poor mRS90 score.

CONCLUSIONS

The DSA-based collateral scoring of the BA large branches might predict long-term outcome in medically treated symptomatic basilar artery stenosis with mild initial severity. Evaluation of BA collateral perfusion status might be useful to determine appropriate treatment strategies.

A leap forward in the endovascular management of acute basilar artery occlusion since the appearance of stent retrievers: a single-center comparative study

OBJECTIVE

Contrary to acute ischemic stroke involving the anterior circulation, no randomized trial has yet demonstrated the safety and effectiveness of endovascular management in acute basilar artery occlusion (BAO). Recently developed thrombectomy devices, such as stentrievers and aspiration systems, have helped in improving the endovascular management of acute ischemic stroke. The authors sought to assess the impact of these devices in the endovascular treatment of acute BAO.

METHODS

A retrospective analysis of 34 consecutive patients treated in Pitié-Salpêtrière Hospital for acute BAO was carried out. All patients had undergone an endovascular procedure. In addition to the global results in terms of safety and effectiveness (recanalization rate and 3-month clinical outcome based on the modified Rankin Scale [mRS]), the authors aimed to determine if the patients treated with the most recently developed devices (i.e., the Solitaire stentriever or the ADAPT catheter) had better angiographic and clinical outcomes than those treated with older endovascular strategies.

RESULTS

The overall successful recanalization rate (thrombolysis in cerebral infarction score 2b–3) was 50% (17 of 34 patients). A good clinical outcome (mRS score 0–2 at 3-month follow-up) was achieved in 11 (32.3%) of 34 patients. The mortality rate at 3-month follow-up was 29.4% (10 of 34 patients). Patients treated with the Solitaire stentriever and the ADAPT catheter had a higher recanalization rate (12 [92.3%] of 13 patients vs 5 [23.8%] of 21 patients, p = 0.0002) and a shorter mean (± SD) procedure duration (88 ± 31 minutes vs 126 ± 58 minutes, p = 0.04) than patients treated with older devices.

CONCLUSIONS

The latest devices have improved the effectiveness of mechanical thrombectomy in acute BAO. Their use in further studies may help demonstrate a benefit in the endovascular management of acute BAO.

The Basilar Artery on Computed Tomography Angiography Prognostic Score for Basilar Artery Occlusion

Background and Purpose—

Basilar artery occlusion is associated with high risk of disability and mortality. This study aimed to assess the prognostic value of a new radiological score: the Basilar Artery on Computed Tomography Angiography (BATMAN) score.

Methods—

A retrospective analysis of consecutive stroke patients with basilar artery occlusion diagnosed on computed tomographic angiography was performed. BATMAN score is a 10-point computed tomographic angiography–based grading system which incorporates thrombus burden and the presence of collaterals. Reliability was assessed with intraclass coefficient correlation. Good outcome was defined as modified Rankin Scale score of ≤3 at 3 months and successful reperfusion as thrombolysis in cerebral infarction 2b-3. BATMAN score was externally validated and compared with the Posterior Circulation Collateral score.

Results—

The derivation cohort included 83 patients with 41 in the validation cohort. In receiver operating characteristic (ROC) analysis, BATMAN score had an area under receiver operating characteristic curve of 0.81 (95% confidence interval [CI], 0.7–0.9) in derivation cohort and an area under receiver operating characteristic curve of 0.74 (95% CI, 0.6–0.9) in validation cohort. In logistic regression adjusted for age and clinical severity, BATMAN score of <7 was associated with poor outcome in derivation cohort (odds ratio, 5.5; 95% CI, 1.4–21; P =0.01), in validation cohort (odds ratio, 6.9; 95% CI, 1.4–33; P =0.01), and in endovascular patients, after adjustment for recanalization and time to treatment (odds ratio, 4.8; 95% CI, 1.2–18; P =0.01). BATMAN score of <7 was not associated with recanalization. Interrater agreement was substantial (intraclass coefficient correlation, 0.85; 95% CI, 0.8–0.9). BATMAN score had greater accuracy compared with Posterior Circulation Collateral score ( P =0.04).

Conclusions—

The addition of collateral quality to clot burden in BATMAN score seems to improve prognostic accuracy in basilar artery occlusion patients.

Aging-related alterations in eNOS and nNOS responsiveness and smooth muscle reactivity of murine basilar arteries are modulated by apocynin and phosphorylation of myosin phosphatase targeting subunit-1

Aging causes major alterations of all components of the neurovascular unit and compromises brain blood supply. Here, we tested how aging affects vascular reactivity in basilar arteries from young (<10 weeks; y-BA), old (>22 months; o-BA) and old (>22 months) heterozygous MYPT1-T-696A/+ knock-in mice. In isometrically mounted o-BA, media thickness was increased by ∼10% while the passive length tension relations were not altered. Endothelial denudation or pan-NOS inhibition (100 µmol/L L-NAME) increased the basal tone by 11% in y-BA and 23% in o-BA, while inhibition of nNOS (1 µmol/L L-NPA) induced ∼10% increase in both ages. eNOS expression was ∼2-fold higher in o-BA. In o-BA, U46619-induced force was augmented (pEC50 ∼6.9 vs. pEC50 ∼6.5) while responsiveness to DEA-NONOate, electrical field stimulation or nicotine was decreased. Basal phosphorylation of MLC20-S19 and MYPT1-T-853 was higher in o-BA and was reversed by apocynin. Furthermore, permeabilized o-BA showed enhanced Ca2+-sensitivity. Old T-696A/+ BA displayed a reduced phosphorylation of MYPT1-T696 and MLC20, a lower basal tone in response to L-NAME and a reduced eNOS expression. The results indicate that the vascular hypercontractility found in o-BA is mediated by inhibition of MLCP and is partially compensated by an upregulation of endothelial NO release.