Basilar artery occlusive disease in the New England Medical Center Posterior Circulation Registry

Intravenous thrombolysis for ischemic stroke in the posterior circulation: A systematic review and meta-analysis

OBJECTIVES

Intravenous thrombolysis (IVT) is recommended in patients with ischemic stroke in the anterior and posterior circulation. Neurological outcomes due to posterior circulation strokes (PCS) without treatment remain poor. Our aim was to overview the literature on outcomes of IVT and conservative treatment in PCS, based on a systematic review and meta-analysis.

METHODS

A systematic literature search was performed on February 27th 2023. Outcome measures included favorable functional outcome at 90 days (modified Rankin Scale [mRS] 0-2), mortality at 90 days, and symptomatic intracranial hemorrhages (sICH). Weighted averages with DerSimonian-Laird approach was used to analyze the data. Subgroup analyses by time window were performed: standard time window (<4.5 hours after symptom onset) and extended time window (>4.5 hours). Analyses were performed using R.

RESULTS

Eight prospective and four retrospective cohort studies were included (n = 1589 patients); no studies with conservative treatment were eligible. The pooled weighted probability regarding favorable functional outcome after IVT was 63 % (95 %CI:0.45-0.78), for mortality 19 % (95 %CI:0.11-0.30), and for sICH 4 % (95 %CI:0.02-0.07). Subgroup analyses showed higher probabilities on achieving favorable functional outcomes for patients treated in the standard (77 %; 95 %CI:0.62-0.88) compared to the extended time window (38 %; 95 %CI:0.29-0.48) with RR = 1.93 (95 %CI:1.66-2.24). Lower probabilities regarding mortality at 90 days and sICH were seen in patients treated in standard compared to extended time window (RR = 0.42, 95 %CI:0.34-0.51 and RR = 0.27, 95 %CI:0.16-0.45, respectively).

CONCLUSIONS

IVT in patients with PCS seems to be safe and effective in standard and extended time window. The effect of IVT is higher in the standard time window.

Chronic basilar artery occlusion: a retrospective monocentric study

BACKGROUND

Acute basilar artery occlusion is a life-threatening medical emergency with a highly elevated mortality rate when left untreated. Little is known about symptoms and clinical progression of chronic occlusions. The aim of this study was to systematically analyze the clinical presentation of patients with chronic basilar artery occlusion (CBAO).

METHODS

Monocentric retrospective analysis of adult patients with CBAO was treated between 2015 and 2023 in the Department of Neurology, Klinikum Kassel. Inclusion criteria were basilar artery occlusion without brainstem infarction as well as patients with a basilar artery occlusion in whom revascularization could not be achieved and a follow-up period of at least 3 months.

RESULTS

A total of 15 patients were found. In five patients basilar artery occlusion was diagnosed as an incidental finding, four patients had neurological symptoms but no proven brainstem infarction (3 × transient ischemic attack, 1 × isolated posterior artery infarct) and six patients presented with acute basilar artery occlusion and a follow-up > 3 months. The most common site of occlusion was midbasilar (80%, n = 12), isolated (n = 7) or in combination with other locations (n = 5). In all cases collateralization could be demonstrated by the posterior communicating arteries. The most common vascular risk factors (VRF) were hypertension (100%) and hypercholesterolemia (67%).

CONCLUSIONS

Patients with CBAO may present with only mild symptoms or may even be asymptomatic. This condition may be survived for a long time. The high percentage of vascular risk factors and further cerebral vessel occlusions suggest arteriosclerosis as the major causing factor of CBAO.

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.

A bibliometric analysis of the 100 most-cited clinical articles in the research of intracranial artery stenosis and intracranial atherosclerosis

Background

Intracranial arterial stenosis (ICAS), caused by intracranial atherosclerosis, is one of the major causes of ischemic stroke. This study identified the top 100 most-cited publications on ICAS through a bibliometric analysis.

Methods

Two independent authors conducted a search in the Web of Science database for clinical articles on ICAS published between 1993 and 2022. The top 100 most-cited articles were then extracted. For each article, the analysis covered the title, author, country of origin/affiliation, journal, total number of citations, number of citations per year, and type of study.

Results

The top 100 most-cited papers in the ICAS were authored by 565 authors from 12 countries and published in 29 journals. In terms of the 5-year trend, the largest number of papers were published between 2003 and 2007 (n = 31). The median number of citations for the 100 papers was 161 (range 109-1,115). The journal with the highest proportion of the 100 most published articles was Stroke, accounting for 41% of articles and 37% of the citations. According to country of origin, the United States of America accounted for the largest number of articles, followed by China, Japan, and South Korea, with these four countries together accounting for 81% of the total number of articles and 88% of the citations. Trends in the past five years included the use of terms such as acute ischemic stroke and mechanical thrombectomy.

Conclusion

The findings of this study provide novel insight into this field and will facilitate future research endeavors.

Presentation of basilar artery stroke secondary to patent foramen ovale: a diagnosis made with a 'selfie'

We report the case of a woman in her late 20s, with no significant medical history, who was found unresponsive at home. Her mother revealed a 'selfie' sent to her by the patient 30 min prior to collapse which revealed bilateral ptoses. Initial brain imaging with non-contrast CT of the brain revealed nil of note. A multiphase CT angiogram revealed an acute basilar artery thrombosis. She underwent timely thrombolysis and was transferred for endovascular thrombectomy. Further evaluation with an aim to define the aetiology revealed the diagnosis of patent foramen ovale with a resultant paradoxical embolism. The differential diagnoses of unexplained rapidly evolving neurology with reduced Glasgow coma scale, and relevant appropriate investigations are discussed in this case report.

Posterior circulation cerebral infarction: A review of clinical, imaging features, management, and outcomes

Objective

This narrative review discusses posterior circulation cerebral infarcts (PCCI) and provides an update given recent randomized trials in the management of basilar artery occlusion (BAO). We examine clinical characteristics, imaging protocols, management updates, and outcomes of PCCI.

Methods

The following databases were searched: MEDLINE, Scopus, Google Scholar, and Web of Science for articles on PCCI. We included randomized trials and observational studies in humans. We also reviewed relevant references from the literature identified.

Results

PCCI and BAO is associated with high morbidity and mortality. Early assessment and accurate diagnosis of PCCI remains a clinical challenge. Neuroimaging advances have improved early detection, but barriers remain due to costs and availability. Recent randomized trials provide new insights for BAO patients and support the efficacy of endovascular thrombectomy.

Discussion

PCCI requires specific diagnostic and management that is distinct from anterior circulation stroke. While further studies are needed in varied populations and in the subset of BAO patients presenting with milder deficits, growing randomized data support the treatment of BAO patients with endovascular thrombectomy.

Basilar artery occlusion: A review of clinicoradiologic features, treatment selection, and endovascular techniques

Basilar artery occlusion (BAO) is an infrequent but often fatal subtype of stroke. Predicting outcomes and selecting patients for endovascular therapy (EVT) remains challenging. Advances in neuroimaging and the development of prognostic scoring systems have augmented clinical decision-making over time. Recent randomized trials, BEST (Basilar Artery Occlusion Endovascular Intervention vs. Standard Medical Treatment), BASICS (Basilar Artery International Cooperation Study), BAOCHE (Basilar Artery Occlusion CHinese Endovascular Trial) and ATTENTION (Endovascular Treatment for Acute Basilar Artery Occlusion), compared EVT and medical management for patients with BAO. These trials yielded mixed results. The former two suggested unclear benefit while the latter two supported a benefit of EVT. While all had limitations, most providers agree caution should be exercised when excluding patients from EVT who may stand to benefit. Further studies are therefore needed to determine the effectiveness, safety, selection criteria, and optimal technical approach for EVT among patients with BAO. Hyperacute-phase advanced imaging can offer several benefits to aid decision making. It is reasonable to exclude patients with low National Institutes of Health Stroke Scale (NIHSS), large imaging-proven cores, and evidence of perforator occlusion by branch atheromatous disease. Herein, we review the clinical presentation, imaging work-up, treatments, and clinical outcomes for BAO, while highlighting knowledge gaps in treatment selection and technique.

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.

Influencing factors of futile recanalization after endovascular therapy for cerebral infarction with posterior circulation occlusion of large vessels: a retrospective study

BACKGROUND

The optimal treatment for cerebral infarction caused by posterior circulation occlusion of large vessels has not yet been determined. Intravascular interventional therapy is an important treatment for cerebral infarction with posterior circulation occlusion of large vessels. However, endovascular therapy (EVT) of some posterior circulation cerebrovascular is ineffective and eventually become futile recanalization. Therefore, we performed a retrospective study to explore the factors influencing futile recanalization after EVT in patients with posterior circulation large-vessel occlusion.

METHODS

Eighty-six patients with acute cerebral infarction and posterior circulation large vessel occlusion after intravascular intervention were divided into two groups according to their modified Rankin scale (mRS) scores after 3 months: group 1, mRS scores less than or equal to 3 (the effective recanalization group); group 2, mRS scores greater than 3 (the ineffective recanalization group). The basic clinical data, imaging index scores, time from onset to recanalization, and operation time between the two groups were compared and analyzed. Logistic regression was used to analyze the factors influencing indicators of good prognosis, and the ROC curve and Youden index were used to determine the best cutoff value.

RESULTS

Between the two groups, there were significant differences in the posterior circulation CT angiography (pc-CTA) scores, GCS scores, pontine midbrain index scores, time from discovery to recanalization, operation time, NIHSS score and incidence of gastrointestinal bleeding. The logistic regression revealed that the NIHSS score and time from discovery to recanalization were associated with good prognoses.

CONCLUSION

NIHSS score and recanalization time were independent influencing factors of ineffective recanalization of cerebral infarctions caused by posterior circulation occlusion. EVT is relatively effective for cerebral infarction caused by posterior circulation occlusion when the NIHSS score is less than or equal to 16 and the time from onset to recanalization is less than or equal to 570 min.

Delayed revascularization in acute ischemic stroke patients

Stroke shares a significant burden of global mortality and disability. A significant decline in the quality of life is attributed to the so-called post-stroke cognitive impairment including mild to severe cognitive alterations, dementia, and functional disability. Currently, only two clinical interventions including pharmacological and mechanical thrombolysis are advised for successful revascularization of the occluded vessel. However, their therapeutic effect is limited to the acute phase of stroke onset only. This often results in the exclusion of a significant number of patients who are unable to reach within the therapeutic window. Advances in neuroimaging technologies have allowed better assessment of salvageable penumbra and occluded vessel status. Improvement in diagnostic tools and the advent of intravascular interventional devices such as stent retrievers have expanded the potential revascularization window. Clinical studies have demonstrated positive outcomes of delayed revascularization beyond the recommended therapeutic window. This review will discuss the current understanding of ischemic stroke, the latest revascularization doctrine, and evidence from clinical studies regarding effective delayed revascularization in ischemic stroke.

Endovascular treatment of acute basilar artery occlusion in patients with and without atrial fibrillation: results from the ATTENTION registry

Background

Previous studies have shown a potential beneficial effect of endovascular therapy (EVT) in patients with acute basilar artery occlusion (BAO). It was unclear that whether atrial fibrillation (AF) can affect the clinical outcomes for BAO patients treated with EVT.

Objectives

To investigate the association between AF and clinical outcomes, and whether AF can modify the efficacy and safety of EVT in patients with BAO.

Design

We conducted a multicenter, nationwide, retrospective analysis to investigate how the presence of AF affects treatment allocation for BAO patients.

Methods

The endovascular treatment for acute basilar artery occlusion (ATTENTION) registry was a multicenter, prospective study in China that included acute BAO patients who underwent EVT or received best medical management (BMM) between 2017 and 2021. The outcomes include the distribution of 3-month modified Rankin scale (mRS) score, functional independence (defined as mRS 0-3), symptomatic intracerebral hemorrhage, and mortality.

Results

2134 patients were included in the study, of which 619 had AF and 1515 did not have AF. The median age was 65 (interquartile range [IQR]: 56-73) years, and 689 (32.3%) patients were female. Multivariate regression analysis indicated no significant association existed between AF and the distribution of mRS (adjusted common odds ratio, 1.05 [95% CI: 0.88, 1.25]; p = 0.564) at 90 days. Similarly, AF was not found to have a significant association with and other measured outcomes, or with the effects of EVT in AF subgroups for at 90 days as measured by ordinal mRS (p for heterogeneity = 0.247). Finally, no significant differences were found for symptomatic intracerebral hemorrhage and mortality within 90 days between the EVT and BMM groups across AF subgroups.

Conclusions

Our results illustrated that the effect of EVT did not differ statistically in acute ischemic stroke patients with and without AF. Moreover, no significant association between AF and functional or safety outcomes could be detected at 90 days.

Mechanical thrombectomy for vertebral and basilar artery occlusions: An institutional experience with 17 patients

Acute ischemic stroke of the posterior circulation as a result of vertebrobasilar artery occlusions is often associated with severe morbidity and mortality rates. Vertebrobasilar artery occlusion retrieval via mechanical thrombectomy (MT) is a novel treatment modality for occlusive strokes. Nevertheless, factors associated with positive outcomes have not yet been adequately investigated. Thus, the present study focused on factors associated with good prognosis following this type of treatment. The present study retrospectively analyzed a series of 17 patients with acute vertebral artery occlusions (VAOs) and basilar artery occlusions (BAOs) treated with MT. In all patients, information such as sex and age, time from admission to the onset of femoral artery access, the number of thrombi removed, the time of femoral artery access to recanalization, pre- and post-operative National Institutes of Health Stroke Scale (NIHSS) scores, pre- and post-operative thrombolysis in cerebral infarction, as well as modified Rankin scale scores were documented and analyzed. The analysis comprised of 11 patients with BAOs and 6 patients with VAOs. A recanalization rate of 70.6% was achieved with an overall good functional outcome of 58.8% at 90 days. Observationally, there was a notable improvement in outcomes when comparing the NIHSS prior to surgery with NIHSS at 1 week after the surgery. A lower NIHSS score prior to MT may be a good prognostic factor. An average time of ~5.5 h from patient admittance to recanalization with a 70.6% recanalization rate with an overall good functional outcome of 58.8% at 90 days suggested that, patients for whom the surgeries were performed within 5 h of admittance may still have hope for recanalization compared to an initial 1.5-h average time for recanalization.

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.

Outcomes of acute basilar artery occlusion-real-world experience in a middle-income country

OBJECTIVES

Our goal was to describe outcomes in a single-center, real-world series of patients with acute basilar artery occlusion in a middle-income country. In addition, we assessed potential outcome predictors.

MATERIAL AND METHODS

Data from 28 patients were retrospectively reviewed. The primary outcome was death until last follow-up. Other outcomes were rates of favorable outcome until last follow-up and rates of intracranial hemorrhage. Outcomes were compared in subgroups according to several variables, including reperfusion (REP group) or no reperfusion (NOREP group) interventions, with chi-squared, Fisher's exact test, or Mann-Whitney tests.

RESULTS

The rate of overall intrahospital death was 46%. Death until last follow-up occurred in 8/17 (47%) in the REP and in 7/11 (63%) of the NOREP group. Favorable outcomes were observed in 35.7% of the patients: 8/17 (47%) in REP and in 2/11 (18.1%) in NOREP. NIH stroke scale scores were significantly lower in patients with favorable outcomes. Intracranial hemorrhage was observed in 6/28 (21.4%) of the patients (all in REP group). Twenty patients were treated with anticoagulants within the first 24 h. No hemorrhage was observed in those treated with enoxaparin, while three occurred in subjects treated with unfractionated heparin.

CONCLUSION

Together with other series, our results underscore the relevance of NIH stroke scale at admission as a prognostic marker, the importance of reperfusion to improve outcomes, and the need of clinical trials to compare the impact of treatment with anticoagulants within first 24 h in basilar artery occlusion.

Posterior Circulation Stroke: Coma (More Than Time) is Brain

BACKGROUND AND PURPOSE

Contrary to anterior circulation, the legitimacy of endovascular treatment in posterior circulation stroke is still being questioned. Finding reliable prognostic factors and determining how patient selection should be done has become top priority.

METHODS

Observational and retrospective study from two Portuguese hospitals, including all consecutive patients with posterior circulation occlusions who underwent thrombectomy between January 1st 2015 and December 31st 2019.

RESULTS

Out of a total of 126 patients, the median age was 74 (IQR 61-80) and 39.7% were female. A good clinical outcome (mRS ≤2) was associated with a lower incidence of coma (24,2% vs 66,7%, p < 0,001) and of sudden onset coma (3% vs 18%,=0,04), a lower NIHSS at admission (14 vs 19, p < 0,001), a higher pc-ASPECTS at admission (10 vs 9, p < 0,001) and at 24 h (8 vs 6, p < 0,001) and a higher BATMAN score (7 vs 6, p = 0,017). Differences in the times of symptom-onset-to-recanalization (496 vs 536, p = 0,19) and symptom-onset-to-coma (130 vs 195, p = 0,52) were not remarkable. When excluding NIHSS and pc-ASPECTS at 24 h, coma (p = 0,003; OR=0,22; 95% CI: 0,08-0,59) and the pc-ASPECTS at admission (p = 0,037; OR=1,63; 95% CI: 1,03-2,57) become independent predictors of good outcome.

CONCLUSIONS

In strokes from the posterior circulation, coma, more than time, appears to be an important prognostic factor. The BATMAN and the pc-ASPECTS scores were also associated with clinical outcome and coma.

Endovascular Treatment for Posterior Circulation Stroke in Routine Clinical Practice: Results of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry

BACKGROUND AND PURPOSE

The benefit of endovascular treatment (EVT) for posterior circulation stroke (PCS) remains uncertain, and little is known on treatment outcomes in clinical practice. This study evaluates outcomes of a large PCS cohort treated with EVT in clinical practice. Simultaneous to this observational study, several intervention centers participated in the BASICS trial (Basilar Artery International Cooperation Study), which tested the efficacy of EVT for basilar artery occlusion in a randomized setting. We additionally compared characteristics and outcomes of patients treated outside BASICS in trial centers to those from nontrial centers.

METHODS

We included patients with PCS from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry: a prospective, multicenter, observational study of patients who underwent EVT in the Netherlands between 2014 and 2018. Primary outcome was a score of 0 to 3 on the modified Rankin Scale at 90 days. Secondary outcomes included reperfusion status and symptomatic intracranial hemorrhage. For outcome comparison between patients treated in trial versus nontrial centers, we used ordinal logistic regression analysis.

RESULTS

We included 264 patients of whom 135 (51%) had received intravenous thrombolysis. The basilar artery was most often involved (77%). Favorable outcome (modified Rankin Scale score 0-3) was observed in 115/252 (46%) patients, and 109/252 (43%) patients died. Successful reperfusion was achieved in 178/238 (75%), and symptomatic intracranial hemorrhage occurred in 9/264 (3%). The 154 nontrial patients receiving EVT in BASICS trial centers had similar characteristics and outcomes as the 110 patients treated in nontrial centers (modified Rankin Scale adjusted cOR: 0.77 [95% CI, 0.5-1.2]).

CONCLUSIONS

Our study shows that high rates of favorable clinical outcome and successful reperfusion can be achieved with EVT for PCS, despite high mortality. Characteristics and outcomes of patients treated in trial versus nontrial centers were similar indicating that our cohort is representative of clinical practice in the Netherlands. Randomized studies using modern treatment approaches are needed for further insight in the benefit of EVT for PCS.

Mechanical Thrombectomy for Anterior versus Posterior Circulation Large Vessel Occlusion Stroke with Emphasis on Posterior Circulation Outcomes

PURPOSE

Although there is class I evidence for mechanical thrombectomy (MT) for anterior circulation large vessel occlusion (LVO) stroke, no high-class evidence exists for the posterior circulation. Here, we sought to compare clinical features of anterior versus posterior LVO as well as predictors of a posterior LVO MT outcome.

METHODS

Patients with acute ischemic stroke who underwent MT for anterior and posterior LVO stroke between February 2016 and August 2020 from 2 comprehensive stroke centers were reviewed. Anterior and posterior LVO strokes were compared. In addition, predictors for a favorable outcome (modified Rankin scale [mRS] 0-3), death (mRS 6), and futile revascularization (mRS 4-6 despite TICI 2b/3 revascularization) for posterior LVO were analyzed.

RESULTS

Collectively, 813 LVO thrombectomy cases were analyzed, and 77 of 813 cases (9.5%) were located in the posterior circulation. Although favorable 90-day functional outcome rates did not differ between anterior and posterior LVO (P = 0.093), death was significantly more frequent among posterior LVO cases (P = 0.013). In the posterior LVO subgroup, a primary aspiration technique and successful revascularization TICI 2b/3 irrespective of time to the intervention were independently associated with achieving a favorable outcome. Primary aspiration was identified to inversely associate with futile revascularization.

CONCLUSION

Anterior and posterior circulation MT patients have distinct clinical profiles. The use of primary aspiration appears fundamental for beneficial outcomes in posterior circulation MT.

Cerebral blood volume index as a predictor of functional independence after basilar artery thrombectomy

BACKGROUND AND PURPOSE

The role of CT perfusion (CTP)in the evaluation of acute basilar artery occlusion (aBAO) patients undergoing endovascular thrombectomy (EVT) is unclear. We investigated the association of individual CTP parameters with functional outcomes in aBAO patients undergoing EVT.

METHODS

A health system's prospectively collected code stroke registry was used in this retrospective analysis of aBAO patients treated with EVT presenting between January 2017 and February 2021 with pre-EVT CTP. The primary outcome measure was modified Rankin Scale (mRS) score 0-2 at 90 days. Factors with a univariate association (p < .05) with mRS 0-2 were combined in a multivariable regression model to determine independent predictors of 90-day favorable functional outcome.

RESULTS

Forty-six subjects, with median age 67 years and median National Institutes of Health Stroke Scale 16, were included, of whom 17 (37%) achieved mRS 0-2 at 90 days. In the multivariable logistic regression model, CTP cerebral blood volume (CBV) index (per 0.1-point increase, odds ratio = 1.843; 95% confidence interval: 1.039, 3.268; p-value .0365) was independently associated with a favorable 90-day outcome.

CONCLUSIONS

CBV index was independently associated with a favorable 90-day outcome in aBAO patients treated with EVT, a novel finding in this patient population. CBV index may assist in treatment and prognosis discussions and inform future studies investigating the role of CTP in aBAO.

Pitfalls in the Diagnosis of Posterior Circulation Stroke in the Emergency Setting

Posterior circulation stroke (PCS), caused by infarction within the vertebrobasilar arterial system, is a potentially life-threatening condition and accounts for about 20–25% of all ischemic strokes. Diagnosing PCS can be challenging due to the vast area of brain tissue supplied by the posterior circulation and, as a consequence, the wide range of—frequently non-specific—symptoms. Commonly used prehospital stroke scales and triage systems do not adequately represent signs and symptoms of PCS, which may also escape detection by cerebral imaging. All these factors may contribute to causing delay in recognition and diagnosis of PCS in the emergency context. This narrative review approaches the issue of diagnostic error in PCS from different perspectives, including anatomical and demographic considerations as well as pitfalls and problems associated with various stages of prehospital and emergency department assessment. Strategies and approaches to improve speed and accuracy of recognition and early management of PCS are outlined.

A Retrospective Study Comparison Between Stenting and Standardized Medical Treatment for Intracranial Vertebrobasilar Stenosis in a Real-World Chinese Cohort

Background: To date, there has been no consensus regarding the benefits of percutaneous transluminal angioplasty and stenting (PTAS) vs. those of standardized medical treatment (SMT) for patients with symptomatic intracranial vertebrobasilar stenosis (IVBS). The purpose of this retrospective study was to compare the effects of PTAS or SMT on symptomatic IVBS in a real-world Chinese population.

Methods: We included 238 patients with ischemic stroke caused by IVBS stenosis who were admitted to Shandong Provincial Hospital Affiliated to Shandong University between September 2012 and May 2018; 62 of these patients were treated with SMT and 176 underwent PTAS. Ischemic stroke in the territory of the responsible artery, hemorrhage, and death within 1 year were recorded as primary endpoints. Secondary endpoints included assessment of stroke severity and the incidence of re-stenosis. The primary endpoint rates were compared between the PTAS and SMT groups at 7 days, 1, 6 months, and 1 year.

Results: In the PTAS group, the success rate of stent placement was 98.9%. During the entire trial, except for 7 days, the SMT group had a higher frequency of primary endpoint events than did the PTAS group. The primary endpoint was 17.7% (11/62) vs. 8.6% (15/174) at 1 month (p = 0.049), 29% (18/62) vs. 14.4% (25/174) at 6 months (p = 0.01), and 32.2% (20/62) vs. 17.2% (30/174) at 1 year (p = 0.013). The restenosis rate of the target lesion was 13.8%; 60% were symptomatic restenosis and 40% were asymptomatic restenosis. The rate of severe stroke at 1 year after PTAS was 0%, while that in the SMT group was 9.7%.

Conclusions: In a real-world Chinese cohort, PTAS for patients might be superior to SMT, and provide better long-term neurological function recovery and lower disability rate.

Outcomes in Endovascular Therapy for Basilar Artery Occlusion: Intracranial Atherosclerotic Disease vs. Embolism

Acute ischemic stroke due to basilar artery occlusion (BAO) carries a very poor prognosis. Functional outcomes in BAO patients undergoing endovascular therapy (EVT) may differ according to the specific pathological mechanisms. We aimed to explore the impact of the underlying pathological mechanisms on prognosis at 90-days and long-term follow-up in BAO patients treated with EVT. We analyzed consecutive BAO patients undergoing EVT from December 2012 to December 2018 at a single center (Xuanwu Hospital). Patients were classified into either an intracranial atherosclerotic disease (ICAD) group or an embolic group according to the corresponding angiographic findings. The baseline characteristics and functional outcomes were compared between the two groups. Multivariable logistic regression analysis was performed. Among the 167 patients enrolled, 78 patients (46.7%) were in the ICAD group and 89 patients (53.3%) were assigned to the embolic group. Overall, 149 patients (89.2%) achieved successful reperfusion post-EVT. There were no significant differences in functional outcomes at 90-days and long-term follow-up between the two groups. Similarly, a Kaplan-Meier survival analysis showed similar long-term survival probabilities (P = 0.438). The pathological mechanism was not associated with functional independence (OR, 1.818; 95% CI, 0.694-4.761; P = 0.224), favorable outcome (OR, 1.476; 95% CI, 0.592-3.681; P = 0.403), or mortality (OR, 1.249; 95% CI, 0.483-3.226; P = 0.646). However, based on subgroup analysis, embolic BAO versus ICAD was significantly associated with better functional independence in those aged 60 years and younger (OR, 4.513; 95% CI, 1.138-17.902). In this study, no differences in either 90-days or long-term functional outcomes between ICAD-related BAO and embolic BAO patients undergoing EVT were observed. However, in BAO patients aged ≤ 60 years, the pathological mechanism of embolism was associated with better functional independence.

Acute Dizziness, Vertigo, and Unsteadiness

Vestibular symptoms, including dizziness, vertigo, and unsteadiness, are common presentations in the emergency department. Most cases have benign causes, such as vestibular apparatus dysfunction or orthostatic hypotension. However, dizziness can signal a more sinister condition, such as an acute cerebrovascular event or high-risk cardiac arrhythmia. A contemporary approach to clinical evaluation that emphasizes symptom duration and triggers along with a focused oculomotor and neurologic examination can differentiate peripheral causes from more serious central causes of vertigo. Patients with high-risk features should get brain MRI as the diagnostic investigation of choice.

Age and discharge modified Rankin score are associated with 90-Day functional outcome after basilar artery occlusion treated with endovascular therapy

INTRODUCTION

Prognostic factors for functional outcome after basilar artery occlusion (BAO) treated with modern endovascular therapy (EVT) are sparse. We investigated the association between clinical characteristics, readily available imaging variables, and outcome in BAO patients treated with EVT.

METHODS

Retrospective analysis from a large healthcare system's prospectively collected code stroke registry of acute BAO patients treated with EVT between January 2017-January 2020. The primary outcome measure was a favorable 90-day modified Rankin score (mRS) of 0-2.

RESULTS

65 patients (median age 67 years, 57% male, median NIHSS 16) met the study inclusion criteria. Thrombolysis in Cerebral Infarction (TICI) 2 b-3 revascularization was achieved in 57/65 patients (88%) with a median time to revascularization of 445 minutes [IQR 302-840]. Ninety-day good outcome was seen in 35% (23/65) of patients. In a univariate analysis, age, history of ischemic stroke, baseline NIHSS, BAO site, and discharge mRS were associated with significant differences between the good and poor outcome groups. A multivariable logistic regression analysis demonstrated an independent association with 90-day good outcome and younger age (per 1-year, OR 0.79, 95% CI 0.64, 0.98) and good discharge mRS (0-2) (OR > 999.99, 95% CI 13.26, > 999.99).

CONCLUSIONS

Patients presenting with an acute BAO treated with modern EVT have a good 90-day outcome in over one-third of cases. Age and discharge mRS are independently associated with good 90-day outcome. Additional studies may focus on factors that can enhance discharge function after BAO, a novel prognostic indicator for favorable 90-day outcome in our study.

Acute ischemic stroke endovascular therapy

Endovascular therapy (EVT) has become the standard treatment for large-vessel occlusion (LVO) acute ischemic stroke (AIS). EVT is now indicated in patients up to 24h from their last known well, provided that the patient meets specific clinical and imaging criteria. Improvements in thrombectomy devices, techniques, and operator experience have allowed successful EVT of ICA terminus, M1-MCA occlusions as well as proximal M2-MCA, basilar artery occlusions, and revascularization of tandem lesions. Mechanical thrombectomy failures still occur due to several factors, however, highlighting the need for further device and technical improvements. An ongoing debate exists regarding the need for pre-EVT thrombolytic agents, thrombectomy techniques, distal occlusions, anesthesia methods, the role of advanced neuroimaging, the treatment of patients with larger infarct core, and those presenting with milder stroke symptoms. Many of these questions are the subject of current or upcoming clinical trials. This review aims to provide an outline and discussion about the established recommendations and emerging topics regarding EVT for LVO AIS.

Effect of manual aspiration thrombectomy using large-bore aspiration catheter for acute basilar artery occlusion: comparison with a stent retriever system

Background

A large-bore aspiration catheter can be employed for recanalization of acute basilar artery occlusion. Here we compare the results of mechanical thrombectomy using a stent retriever (SR) and manual aspiration thrombectomy (MAT) using a large-bore aspiration catheter system as a first-line recanalization method in acute basilar artery occlusion (BAO).

Methods

The records of 50 patients with acute BAO who underwent mechanical thrombectomy were retrospectively reviewed. Patients were assigned to one of two groups based on the first-line recanalization method. The treatment and clinical outcomes were compared.

Results

Sixteen (32%) patients were treated with MAT with a large-bore aspiration catheter and 34 (68%) with a SR as the first-line treatment method. The MAT group had a shorter procedure time (28 vs. 65 min; p = 0.001), higher rate of first-pass recanalization (68.8% vs. 38.2%, p = 0.044), and lower median number of passes (1 vs 2; p = 0.008) when compared with the SR group. There was no significant difference in the incidence of any hemorrhagic complication (6.3% vs. 8.8%; p = 0.754) between the groups. However, there were four cases of procedure-related subarachnoid hemorrhage (SAH) in the SR group and one death occurred due to massive hemorrhage.

Conclusions

Selection of MAT using a large-bore aspiration catheter for acute BAO may be a safe and effective first-line treatment method with higher first-pass recanalization rate and shorter procedure time than SR.

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.

Wake-Promoting Effect of Bloodletting Puncture at Hand Twelve Jing-Well Points in Acute Stroke Patients: A Multi-center Randomized Controlled Trial

OBJECTIVE

To assess the effect and safety of bloodletting puncture at hand twelve Jing-Well points (HTWPs) in acute stroke patients with conscious disturbance.

METHODS

In this multi-center and randomized controlled trial, 360 patients suffered from ischemic or hemorrhagic stroke with conscious disturbance within 48 h from the onset of symptom were divided into bloodletting (180 cases) and control (180 cases) groups using a block randomization. Patients in both groups received routine Western medicine, and patients in the bloodletting group received additional bloodletting puncture at HTWPs on admission immediately before conventional treatment. The primary outcome measure was Glasgow Coma Scale (GCS) score and the secondary outcomes included blood pressure, respiratory rate and pulse rate. All variables were evaluated at baseline (before bloodletting), 0 (after bloodletting immediately), 15, 30, 50 and 80 min post bloodletting.

RESULTS

At 80 min post bloodletting, the proportion of patients with improved consciousness in the bloodletting group was greater than the control group (P<0.05). In the separate analysis of moderate consciousness disturbance subgroup, bloodletting therapy benefited ischemic patients, and improved the eye and language response of GCS score at 15, 30, 50, 80 min post bloodletting (P<0.05 or P<0.01). No significant differences were observed regarding the secondary outcomes between two groups (P>0.05).

CONCLUSION

The bloodletting puncture at HTWPs was safe and could improve conscious levels of ischemic stroke patients, highlighting a first-aid intervention for acute stroke. (Registration No. ChiCTR-INR-16009530).

Analysis of Treatment Outcome After Endovascular Treatment in Different Pathological Subtypes of Basilar Artery Occlusion: a Single Center Experience

The current study aimed to evaluate whether patients with different pathologic subtypes of basilar artery occlusion (BAO) stroke could affect the clinical outcome after receiving endovascular treatment (EVT). A total of 187 consecutive patients with acute BAO receiving endovascular treatment (EVT) from January 2012 to July 2018 at the Beijing Tiantan Hospital were recruited in this study. The patients were categorized into three groups: embolism without vertebral artery (VA) steno-occlusion (group 1), in situ atherosclerotic thrombosis (group 2), and embolism from tandem VA steno-occlusion (group 3). Among the 187 patients, 4 patients with embolic combined with ICAS and 1 patient with tandem VA steno-occlusion combined with ICAS were excluded. Of the remaining 182 patients (153 men and 29 women; mean age, 60 years), 43 (23.6%) had embolism without vertebral artery (VA) steno-occlusion (group 1), 116 (63.7%) showed in situ atherosclerotic thrombosis (group 2), and 23 (12.6%) had embolism from tandem VA steno-occlusion (group 3). Overall, successful recanalization (modified thrombolysis in cerebral infarction grade 2b or 3) was achieved in 95.3%, 86.2%, and 60.9% in groups 1, 2, and 3, respectively. The favorable outcome (90-day modified Rankin scale score, 0-3) in the three groups was 51.2%, 52.6%, and 30.4%, respectively. Mortality was higher in group 3 (47.8%) as compared with groups 1 (16.3%) (p = 0.009) and 2 (17.2%) (p = 0.004). Embolism from tandem VA steno-occlusion (group 3) seems to be associated with a lower rate of recanalization and significantly higher rate of mortality as compared with another pathological mechanism of BAO.

Intracranial collaterals and arterial wall features in severe symptomatic vertebrobasilar stenosis

BACKGROUND AND AIMS

The protective role of intracranial primary collaterals on plaque vulnerability is not well established. We aimed to explore the association of intracranial collateral status with arterial wall features including arterial remodeling and culprit plaque features in severe symptomatic intracranial vertebrobasilar atherosclerosis (sIVBAS).

METHODS

Posterior circulation stroke or TIA patients owing to sIVBAS from a three-dimensional high-resolution MRI (3D HRMRI) prospective observational study was included for current analysis. Participants were dichotomized into poor and good collateral groups according to a modified semiquantitative grading system for primary collateral of posterior circulation. Differences of arterial remodeling, culprit plaque distribution, enhancement, intraplaque hemorrhage (IPH), and calcification on HRMRI were compared between the two groups.

RESULTS

Seventy-four eligible patients were included, wherein 39 in poor collateral group and 35 in good collateral group. The average age was 57.0 ± 9.0 years, 65 (87.8%) were male, 62 (83.8%) were diagnosed with ischemic stroke and 12 (16.2%) with TIA. Patients with good collateral had lower occurrence of arterial positive remodeling and plaque diffuse distribution, enhancement (Adjusted OR = 0.17 [0.05-0.54], p < 0.01; adjusted OR = 0.26 [0.06-0.99], p = 0.05; adjusted OR = 0.17 [0.03-0.96], p = 0.04, respectively). No significant differences on IPH and calcification were found between poor and good collateral group (p > 0.05).

CONCLUSION

Intracranial good collateral of posterior circulation may be associated with lower risk of arterial positive remodeling and culprit plaque diffuse distribution, plaque enhancement in patients with severe sIVBAS.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02705599.

Brainstem iron overload and injury in a rat model of brainstem hemorrhage

BACKGROUND AND PURPOSE

Brainstem hemorrhage (BSH) is the most devastating subtype of intracerebral hemorrhage (ICH) with the highest mortality ranging from 56 % to 61.2 %. However, there is no effective medical or surgical therapy to improve its outcomes in clinic to date due to lack of understanding of its injury mechanisms. Herein, we explored the brainstem iron overload and injury in a rat model of BSH.

METHODS

Neurological scores were examined on day 1, 3, and 7 after modeling, and mortality of the rats was recorded to draft a survival curve. Rats were monitored by MRI using T2 and susceptibility weighted imaging (SWI) before sacrifice for examination of histology and immunofluorescence on day 1, 3, and 7.

RESULTS

BSH rats had a high mortality of 56 % and demonstrated the severe neurological deficits mimicking the clinical conditions. SWI showed that the same increasing tendency in change of hypointense area with that in iron deposition by Perls staining from day 1 to 7. Expression of heme oxygenase 1 (HO-1) and generation of reactive oxygen species (ROS) had similar tendency and both peaked on day 3. Neuronal degeneration occurred and stayed elevated from day 1 to 7, while myelin sheath injury was initially observed on day 1 but without significant difference within 7 days.

CONCLUSIONS

The time courses of erythrocyte lysis, HO-1 expression, iron deposition and ROS generation are related to each other after BSH. Besides, brainstem injury including neuronal degeneration and myelin damage were observed and discussed.

Safety and Blood-Flow Outcomes for Hybrid Recanalization in Symptomatic Refractory Long-Segmental Vertebral Artery Occlusion-Results of a Pilot Study

Objective: Hybrid recanalization for vertebral artery (VA) long-segmental occlusion using a combination of ostial vertebral endarterectomy and distal endovascular stenting has achieved technical success. The safety and efficacy of the hybrid technique should be further evaluated.

Methods: We examined a cohort of refractory patients with long-segmental occlusion in the VA and low flow in the basilar artery (BA). The hybrid technique was performed to achieve the recanalization of VA. Angiograms were analyzed for occlusive length, contralateral VA status and collaterals. Clinical variables, including 30-days outcomes and blood-flow changes within 6 months based on quantitative magnetic resonance angiography (qMRA) with non-invasive optimal vessel analysis (NOVA), were collected pre- and post-operatively.

Results: Among 290 consecutive cases with VA initial segment stenosis or occlusion, 14 patients (13 male and 1 female) with symptomatic long-segmental VA occlusion and low flow in the BA were refractory to the best standard medical therapy. The hybrid technique was successful in obtaining recanalization in all but one patient. The mean follow-up period was 17.2 ± 9.2 months. One patient had new ischemic deficits within seven days of the operation. Four patients suffered from transient Horner syndrome postoperatively, but had recovered completely by the 6-months follow-up. Within this period, all revascularization was visible with computed tomography angiography (CTA), and the blood-flow in the BA improved significantly (66.4 ± 15.3 ml/min vs. 104.0±12.9 ml/min, P < 0.05) within 6 months. No ischemic events recurred during follow-up.

Conclusions: The hybrid technique is potentially a safe and feasible method to achieve recanalization and improve hemodynamic compromise for long-segmental VA occlusion.

Assessment of Vessel Density on Non-Contrast Computed Tomography to Detect Basilar Artery Occlusion

Introduction

Basilar artery occlusion (BAO) may be clinically occult due to variable and non-specific symptomatology. We evaluated the qualitative and quantitative determination of a hyperdense basilar artery (HDBA) on non-contrast computed tomography (NCCT) brain for the diagnosis of BAO.

Methods

We conducted a case control study of patients with confirmed acute BAO vs a control group of suspected acute stroke patients without BAO. Two EM attending physicians, one third-year EM resident, and one medical student performed qualitative and quantitative assessments for the presence of a HDBA on axial NCCT images. Our primary outcome measures were sensitivity and specificity for BAO. Our secondary outcomes were inter-rater and intra-rater reliability of the qualitative and quantitative assessments.

Results

We included 60 BAO and 65 control patients in our analysis. Qualitative assessment of the hyperdense basilar artery sign was poorly sensitive (54%–72%) and specific (55%–89%). Quantitative measurement improved the specificity of hyperdense basilar artery assessment for diagnosing BAO, with a threshold of 61.0–63.8 Hounsfield units demonstrating relatively high specificity of 85%–94%. There was moderate inter-rater agreement for the qualitative assessment of HDBA (Fleiss’ kappa statistic 0.508, 95% confidence interval: 0.435–0.581). Agreement improved for quantitative assessments, but still fell in the moderate range (Shrout-Fleiss intraclass correlation coefficient: 0.635). Intra-rater reliability for the quantitative assessments of the two attending physician reviewers demonstrated substantial consistency.

Conclusion

Our results highlight the importance of carefully examining basilar artery density when interpreting the NCCT of patients with altered consciousness or other signs and symptoms concerning for an acute basilar artery occlusion. If the Hounsfield unit density of the basilar artery exceeds 61 Hounsfield units, BAO should be highly suspected.

The "distal-to-proximal" strategy for the treatment of posterior circulation tandem occlusions: a single-centre experience

PURPOSE

Data on posterior circulation tandem occlusions in acute ischemic stroke are scarce: recognition may be challenging and little is known about optimal treatment strategy. We report our endovascular treatment strategy for posterior circulation tandem occlusion.

METHODS

Consecutive patients with posterior circulation tandem occlusions in our centre were enrolled retrospectively. The preferred strategy was "distal-to-proximal" strategy, which means opening the distal occlusion first followed by treatment of the proximal pathology. The imaging characteristics, treatment strategy, clinical outcomes, and complications of patients with posterior circulation tandem occlusions were analyzed.

RESULTS

In total, 21 patients with posterior circulation tandem occlusions were enrolled in the study, which accounted for 23.6% of patients with posterior circulation stroke in our centre. The mean age was 60 years (range 32 to 80), and median pre-procedure NIHSS score was 28 (interquartile range: 13-31). Eighteen patients (85.7%) had vertebrobasilar artery tandem occlusions and 3 (14.3%) had basilar artery to basilar artery tandem occlusions. All distal occlusions were successfully recanalized (modified TICI 2b/3). Two (9.5%) of the proximal lesions were not treated. A total of 57.1% of the patients had stents implanted on the proximal occlusions. The rate of mRS 0-3 at 3 months was 57.1% and the mortality rate was 19.0%.

CONCLUSION

In patients with acute ischaemic stroke caused by posterior circulation tandem occlusions, we favor "distal-to-proximal" strategy based on the positive results in this small series. Nevertheless, a more extensive study is required to explore the optimal treatment strategy further.

Significance of angiographic clot meniscus sign in mechanical thrombectomy of basilar artery stroke

Introduction

The relationship between the occlusive clot morphology and the efficacy of mechanical thrombectomy (MT) in basilar artery occlusion (BAO) is not well known. Our aim was to evaluate the clinical significance of the clot meniscus sign in patients with acute BAO.

Methods

89 patients with acute BAO who underwent MT were retrospectively analyzed. The clot meniscus sign was defined as meniscoid/tram-track like antegrade side-wall contrast opacification of the thrombus. Patients were assigned to two groups based on the presence of the clot meniscus sign. The treatment and clinical outcomes were compared.

Results

The clot meniscus sign was diagnosed in 62.9% (53/89) of the patients. The meniscus sign (+) group showed a shorter procedure time (55 vs 85 min; p=0.045), higher rate of successful recanalization (89.3% vs 63.6%, p=0.004), higher incidence of first pass effect (32.1% vs 6.1%, p=0.004), and lower number of passes (2 vs 3; p=0.042) when compared with the meniscus sign (−) group. The procedure time (OR 0.972, 95% CI 0.962 to 0.992; p=0.003) and clot meniscus sign (OR 7.920, 95% CI 1.769 to 35.452; p=0.007) were independent predictors of successful recanalization.

Conclusion

The clot meniscus sign is related to high first pass effect and short procedure time and is a reliable predictor of successful recanalization in patients with acute BAO.

Is Functional Outcome Different in Posterior and Anterior Circulation Stroke?

Background and Purpose- Posterior circulation stroke (PCS) account for 20% of all ischemic strokes. There is limited evidence whether functional outcome of PCS is comparable to that of anterior circulation stroke (ACS). We aimed to analyze whether 3-month functional outcome is different in PCS and ACS. Methods- Patients with acute ischemic stroke prospectively enrolled within the Austrian Stroke Unit Registry were stratified by infarct localization according to the Oxfordshire Community Stroke Project Classification. Propensity score matching was used to control for covariate imbalances and to match patients with PCS and ACS. Patients were matched for stroke severity, recombinant tissue-type plasminogen activator treatment, and demographic and vascular risk factors. Main outcomes were the distribution of modified Rankin Scale after 3 months and multiple proportional odds models to estimate the influence of the infarct localization on the functional outcome. Results- From a total of 90 484 patients enrolled within the Austrian Stroke Unit Registry, 9208 (4604 PCS/4604 ACS) were matched, of those 954 (477 in each group) were treated with recombinant tissue-type plasminogen activator. We detected a significant shift towards better 3-month functional outcome in patients with ACS compared with PCS (odds ratio [OR], 1.19; 95% CI, 1.1-1.28; P<0.0001). In particular, functional outcome was worse in PCS with onset-to-door-time >270 minutes (OR, 1.34; 95% CI, 1.17-1.54; P<0.0001) and in PCS with unknown onset-to-door-time (OR, 1.26; 95% CI, 1.13-1.42; P<0.0001); however, we did not detect any difference in functional outcome between ACS and PCS in patients with an onset-to-door-time ≤270 minutes (1-180 minutes: OR, 0.92, 95% CI, 0.78-1.09, P=0.3554; 181-270 minutes: OR, 1.04, 95% CI, 0.79-1.37, P=0.7689). In patients treated with recombinant tissue-type plasminogen activator, functional outcome was not significantly different between PCS and ACS. Conclusions- PCS was associated with worse outcome compared with ACS in patients arriving later than 4.5 hours at hospital or in those with unknown onset of symptoms. Our results urge for implementation of symptoms found in the posterior circulation into preclinical patient-triage tools.

Current endovascular strategies for posterior circulation large vessel occlusion stroke: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

Background

The aim of this publication is to provide a detailed update on the diagnosis, treatment, and endovascular techniques for posterior circulation emergent large vessel occlusion (pc-ELVO).

Methods

We performed a review of the literature to specifically evaluate this disease and its treatments.

Results

Data were analyzed, and recommendations were reported based on the strength of the published evidence and expert consensus.

Conclusion

While many questions about pc-ELVO remain to be studied, there is evidence to support particular practices in its evaluation and treatment.

Mechanical Thrombectomy in Subtypes of Basilar Artery Occlusion: Relationship to Recanalization Rate and Clinical Outcome

Background Acute stroke because of basilar artery occlusion (BAO) represents 1% of all ischemic strokes. However, recanalization rates and treatment outcome for the different pathologic subtypes of BAO stroke are not fully understood. Purpose To compare the recanalization rate and clinical outcomes of mechanical thrombectomy in different subtypes of BAO. Materials and Methods Eighty-two patients (46 men and 36 women; mean age, 73 years; age range, 20-90 years; mean age in men, 70 years [age range, 20-90 years]; mean age in women, 75 years [age range; 61-90 years]) with acute BAO who underwent mechanical thrombectomy between March 2010 and December 2017 were retrospectively analyzed. Patients were classified into three groups: embolism without vertebral artery (VA) steno-occlusion (group 1), embolism from tandem VA steno-occlusion (group 2), and in situ atherosclerotic thrombosis (group 3). Clinical and angiographic characteristics, recanalization rate, procedure times, and clinical outcomes were compared between groups by using the Kruskal-Wallis, Pearson χ², and Fisher exact tests. Results The incidence of BAO according to stroke mechanism were as follows: group 1, n = 34 (41%); group 2, n = 28 (34%), group 3, n = 20 (24%). Overall, successful recanalization (modified Thrombolysis in Cerebral Infarction grade 2b or 3) was achieved in 78% (64 of 82) and favorable outcome (90-day modified Rankin Scale score, 0-2) in 37% (30 of 82) of the patients. The procedure time was shorter in group 1 than in group 2 (49 vs 66 minutes, respectively; P = .01). Group 1 showed a higher successful recanalization rate than group 3 (29 of 34 [85%] vs 11 of 20 [55%], respectively; P = .01). Good clinical outcome rate was higher in group 1 than in group 3 (18 of 34 [53%] vs four of 20 [20%], respectively; P = .02). Conclusion The outcome of mechanical thrombectomy for basilar artery occlusion differs according to the pathologic mechanism of stroke; the best outcomes and recanalization rate occurred in patients with embolism without vertebral artery steno-occlusion. © RSNA, 2019 See also the editorial by Hetts in this issue.

Visualization of basilar artery atherosclerotic plaques by conventional T2-weighted magnetic resonance imaging: A case-control study

Objective

In vivo visualization of intracranial atherosclerotic plaque has been performed only with high-resolution magnetic resonance imaging (HRMR). We investigated whether atherosclerotic plaque of the basilar artery (BA) can be identified in conventional magnetic resonance imaging (MRI).

Methods

Patients with acute ischemic stroke who had BA stenosis (“symptomatic BAA”) were retrospectively recruited using the prospective stroke registry. In the HRMR databank, subjects without BA stenosis were recruited and classified as those with silent plaque (“silent BAA”) and without any plaque (“normal controls”). Outer diameter of the BA and T2 plaque sign (an eccentric or complete obscuration of normal flow-void) within the BA were assessed by two blinded raters using conventional T2 MRI.

Results

Seventy-five patients with symptomatic BAA, 40 with asymptomatic BAA, and 36 normal controls were included in the study. Maximal BA diameter was significantly larger in symptomatic BAA patients with <30%, 30–50%, 50–70%, and >70% stenosis (all p<0.01 in each subgroup) and silent BAA subjects (p = 0.018) than controls. T2 plaque signs were present in 46 (61.3%) patients with symptomatic BAA and 6 (14.6%) subjects with asymptomatic BAA, while none in normal controls (p <0.001 and 0.057, respectively). Detection rates were increased with an increase in stenosis degree (25.0% in <30% stenosis, 57.9% in 30–50% stenosis, 38.5% in 50–70% stenosis, 92.3% in 70–99% stenosis, and 100.0% in occlusion).

Conclusions

Our data suggest that BA atherosclerosis can be detected by conventional MRI. When the use of HRMR is limited, conventional MR imaging may give additive information to clinicians.

Therapy for acute basilar artery occlusion: a systematic review and meta-analysis

Purpose: This study aims to analyse the efficacy of different treatment methods for acute basilar artery occlusion, with an emphasis placed on evaluating the latest treatment methods. Method:  A systematic review and meta-analysis was performed to analyse the current data on the therapies available for treating acute basilar artery occlusion. Results: A total of 102 articles were included. The weighted pooled rate of mortality was 43.16% (95% CI 38.35-48.03%) in the intravenous thrombolysis group, 45.56% (95% CI 39.88-51.28) in the intra-arterial thrombolysis group, and 31.40% (95% CI 28.31-34.56%) for the endovascular thrombectomy group. The weighted pooled rate of Modified Ranking Score (mRS) 0-2 at 3 months was 31.40 (95% CI 28.31-34.56%) in the IVT group, 28.29% (95% CI 23.16-33.69%) in the IAT group, and 35.22% (95% CI 32.39-38.09%) for the EVT group. Meta-analyses were also done for the secondary outcomes of recanalization and symptomatic haemorrhage. There was no difference between stent retriever and thrombo-aspiration thrombectomy on subgroup analysis in both clinical outcome and safety profile. Limitations: The included studies were observational in nature. There was significant heterogeneity in some of the outcomes. Conclusions:  Superior outcomes and better recanalization rates for acute basilar occlusion were seen with patients managed with endovascular thrombectomy when compared with either intravenous and/or intraarterial thrombolysis. No superiority of stent-retrievers over thrombo-aspiration thrombectomy was seen.