Does Device Selection Impact Recanalization Rate and Neurological Outcome?

Endovascular treatment of acute ischemic stroke in childhood: A comprehensive literature review based on the experience of a single center

Acute ischemic stroke (AIS) in childhood is a relatively rare but significant condition that can result in long-term disabilities. There is a lack of standardized strategies for diagnosing and treating pediatric AIS due to limited evidence-based data on thrombolytic and endovascular treatments in children. This comprehensive literature review focuses on the experience of a single center in Italy and aims to highlight the main peculiarities of endovascular treatment (EVT) for AIS in childhood. The review covers the diagnostic workup, the endovascular procedures, and the need for a specific thrombectomy program for pediatric AIS. The review discusses the indications and considerations for thrombectomy in children, including the risk of complications and the challenges of extrapolating results from adult studies. The diagnostic protocols for pediatric AIS are also discussed, emphasizing the use of MRI to avoid X-ray and contrast medium exposure in children. The combination of intravenous thrombolysis and mechanical thrombectomy has been examined, considering the differences between pediatric and adult thrombi. Technical considerations related to the size of pediatric patients are addressed, including the use of large bore catheters and potential concerns with access points. The organization of a thrombectomy program for pediatric AIS is discussed, emphasizing the need for specialized facilities and expertise. Although evidence for EVT in the pediatric population is based on case series, the importance of specialized centers and the lack of validated guidelines are evident.

Mechanical Thrombectomy for Pediatric Large Vessel Occlusions : A Systematic Review and Meta-analysis

BACKGROUND

Acute intracranial large vessel occlusion (LVO) is an important cause of morbidity and mortality among children; however, unlike in adults, no clinical trial has investigated the benefit of mechanical thrombectomy (MT) in pediatric LVO. Thus, MT remains an off-label procedure for pediatric stroke.

PURPOSE

To investigate the efficacy and safety of MT in pediatric LVO.

METHODS

A systematic literature search was conducted in Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, and Cochrane Central Register of Clinical Trials databases. Studies reporting safety and efficacy outcomes for endovascular treatment of pediatric LVO were included. Data regarding recanalization, functional outcome, symptomatic intracranial hemorrhage (sICH), and mortality were extracted from the included studies. Functional outcome was assessed with the modified Rankin scale (mRS). A fixed or random-effects model was used to calculate pooled event rates and 95% confidence intervals (CI).

RESULTS

In this study 11 studies comprising 215 patients were included. The successful recanalization rate was 90.3% (95% CI = 85.77-95.11%), and complete recanalization was achieved in 52.7% (95% CI = 45.09-61.62%) of the cases. The favorable (mRS = 0-2) and excellent (mRS = 0-1) outcome rates were 83.3% (95% CI = 73.54-94.50%) and 59.5% (95% CI = 44.24-80.06%), respectively. The overall sICH prevalence was 0.59% (95% CI = 0-3.30%) and mortality rate was 3.2% (95% CI = 0.55-7.38%).

CONCLUSION

In our meta-analysis, MT demonstrated a promising safety and efficacy profile for pediatric patients, with consistently high efficacy outcomes and low complication rates. Our results support the utilization of MT in pediatric LVOs; however, prospective studies are still needed to further establish the role of pediatric MT as a first-line treatment strategy.

Pediatric Interventional Neuroradiology

Pediatric neurovascular disorders can lead to substantial mortality and morbidity if not diagnosed early and adequately managed. Children with neurovascular diseases cannot be treated as small adults as the vascular and central nervous system anatomy, physiology, and pathologies in children differ greatly from those of adults. In addition, some neurovascular pathologies are seen exclusively in children such as aneurysmal malformation of the vein of Galen, pial fistulas, and dural fistulas in the context of dural sinus disease. In this review, we aim to present an overview of the common pediatric neurovascular diseases along with their endovascular management.

Impact of edema formation on functional outcome in pediatric stroke patients

BACKGROUND

Quantitative lesion net water uptake (NWU) has been described as an imaging biomarker reflecting vasogenic edema as an early indicator of infarct progression. We hypothesized that edema formation measured by NWU is higher in children compared to adults but despite this functional outcome may be better in children.

METHODS

This study analyzed children enrolled in the Save ChildS Study who had baseline and follow-up computed tomography available and the data were compared to adult patients.

RESULTS

Some 207 patients, of whom 13 were children and 194 were adults, were analyzed. Median NWU at baseline was 7.8% (IQR: 4.3-11.3), and there were no significant differences between children and adults (7.5% vs. 7.8%; p = 0.87). The early edema progression rate was 3.0%/h in children and 2.3%/h in adults. Median ΔNWU was 15.1% in children and 10.5% in adults. Children had significantly more often excellent (mRS 0-1; children 10/13 = 77% vs. adults 28/196 = 14%; p < 0.0001) and favorable clinical outcomes (mRS 0-2, 12/13 = 92% vs. 39/196 = 20%; p < 0.0001).

CONCLUSIONS

In this study, clinical outcomes in children with large vessel occlusion strokes were better than in adults despite similar clinical and imaging characteristics and similar edema formation. This may be impacted by the generally better outcomes of children after strokes but may demonstrate that the degree of early ischemic changes using Alberta Stroke Program Early Computed Tomography Score (ASPECTS) and edema progression rate may not be a reason for exclusion from endovascular thrombectomy.

Childhood stroke

Stroke is an important cause of neurological morbidity in children; most survivors have permanent neurological deficits that affect the remainder of their life. Stroke in childhood, the focus of this Primer, is distinguished from perinatal stroke, defined as stroke before 29 days of age, because of its unique pathogenesis reflecting the maternal-fetal unit. Although approximately 15% of strokes in adults are haemorrhagic, half of incident strokes in children are haemorrhagic and half are ischaemic. The causes of childhood stroke are distinct from those in adults. Urgent brain imaging is essential to confirm the stroke diagnosis and guide decisions about hyperacute therapies. Secondary stroke prevention strongly depends on the underlying aetiology. While the past decade has seen substantial advances in paediatric stroke research, the quality of evidence for interventions, such as the rapid reperfusion therapies that have revolutionized arterial ischaemic stroke care in adults, remains low. Substantial time delays in diagnosis and treatment continue to challenge best possible care. Effective primary stroke prevention strategies in children with sickle cell disease represent a major success, yet barriers to implementation persist. The multidisciplinary members of the International Pediatric Stroke Organization are coordinating global efforts to tackle these challenges and improve the outcomes in children with cerebrovascular disease.

Cost-Effectiveness of Endovascular Thrombectomy in Childhood Stroke: An Analysis of the Save ChildS Study

Background and Purpose

The Save ChildS Study demonstrated that endovascular thrombectomy (EVT) is a safe treatment option for pediatric stroke patients with large vessel occlusions (LVOs) with high recanalization rates. Our aim was to determine the long-term cost, health consequences and cost-effectiveness of EVT in this patient population.

Methods

In this retrospective study, a decision-analytic Markov model estimated lifetime costs and quality-adjusted life years (QALYs). Early outcome parameters were based on the entire Save ChildS Study to model the EVT group. As no randomized data exist, the Save ChildS patient subgroup with unsuccessful recanalization was used to model the standard of care group. For modeling of lifetime estimates, pediatric and adult input parameters were obtained from the current literature. The analysis was conducted in a United States setting applying healthcare and societal perspectives. Probabilistic sensitivity analyses were performed. The willingness-to-pay threshold was set to $100,000 per QALY.

Results

The model results yielded EVT as the dominant (cost-effective as well as cost-saving) strategy for pediatric stroke patients. The incremental effectiveness for the average age of 11.3 years at first stroke in the Save ChildS Study was determined as an additional 4.02 lifetime QALYs, with lifetime cost-savings that amounted to $169,982 from a healthcare perspective and $254,110 when applying a societal perspective. Acceptability rates for EVT were 96.60% and 96.66% for the healthcare and societal perspectives.

Conclusions

EVT for pediatric stroke patients with LVOs resulted in added QALY and reduced lifetime costs. Based on the available data in the Save ChildS Study, EVT is very likely to be a cost-effective treatment strategy for childhood stroke.

Acute StrokeTreatment in Children: Are Adult Guidelines Applicable?

Purpose of this Review

This article provides an overview into acute treatments in stroke which are widely studied and available for adults and their applicability in the pediatric population.

Recent Findings

Arterial ischemic stroke is an important cause of morbidity and mortality in the pediatric population. Neurological deficits and etiologies are age-dependent and more challenging to diagnose than in the adult population. Advancements in imaging and treatment modalities including increased treatment windows in acute stroke have led to improvement in the diagnosis and management of pediatric arterial ischemic disease. Accordingly, hyperacute treatments, such as endovascular therapy, are becoming increasingly available in an attempt to improve outcomes in children.

Summary

Significant scientific and technological advances have transformed the hyperacute treatment of stroke in the recent years, allowing for improvement in the diagnosis and treatment of cerebrovascular pathologies in children. Optimization in the approach, and validation of existing stroke pathways/protocols is expected to further advance acute stroke therapy in pediatric patient care. Given that the lifelong individual, family, and societal burden of acute stroke is likely to be greater than in adults because infants and children surviving stroke live more years with disability, we must be knowledgeable about this pathology and the medical and therapeutic options available for this unique population as detailed in this review.

Complete functional recovery in a child after endovascular treatment of basilar artery occlusion caused by spontaneous dissection: a case report

Stroke caused by dissection of arteries of the vertebrobasilar system in children is still poorly investigated in terms of etiology, means of treatment, course of disease, and prognosis. The aim of this report was to describe the unusual course of a spontaneous dissection of the basilar artery (BA) in a child treated with endovascular techniques and to point out that the plasticity of the brain stem can fully compensate for structural damage caused by stroke. We report the case of a 15-year-old boy who suffered a wake-up stroke with BA occlusion caused by spontaneous dissection. A blood clot was aspirated from the false lumen and the true lumen re-opened, but the patient deteriorated a few hours later, and repeated angiography revealed that the intimal flap was detached, occluding the BA again. The lumen of BA was then reconstructed by a stent. Despite a large pons infarction, the patient was completely recovered 11 months after the onset. The case was analyzed with angiograms and magnetic resonance imaging, macroscopic and microscopic pathological analysis, computed tomographic angiography, magnetic resonance-based angiography, and diffusion tensor imaging. This case illustrates that applied endovascular techniques and intensive care measures can alter the course of potentially fatal brain stem infarction. Our multimodal analysis gives new insight into the anatomical basis for the plasticity mechanism of the brain stem.

Acute ischemic stroke in childhood: a comprehensive review

This review provides an updated analysis of the main aspects involving the diagnosis and the management of children with acute ischemic stroke. Acute ischemic stroke is an emergency of rare occurrence in children (rate of incidence of 1/3500 live birth in newborns and 1-2/100,000 per year during childhood with peaks of incidence during the perinatal period, under the age of 5 and in adolescence). The management of ischemic stroke in the paediatric age is often challenging because of pleomorphic age-dependent risk factors and aetiologies, high frequency of subtle or atypical clinical presentation, and lacking evidence-based data about acute recanalization therapies. Each pediatric tertiary centre should activate adequate institutional protocols for the optimization of diagnostic work-up and treatments.Conclusion: The implementation of institutional standard operating procedures, summarizing the steps for the selection of candidate for neuroimaging among the ones presenting with acute neurological symptoms, may contribute to shorten the times for thrombolysis and/or endovascular treatments and to improve the long-term outcome. What is Known: •Acute ischemic stroke has a higher incidence in newborns than in older children (1/3500 live birth versus 1-2/100,000 per year). •Randomized clinical trial assessing safety and efficacy of thrombolysis and/or endovascular treatment were never performed in children What is New: •Recent studies evidenced a low risk (2.1% of the cases) of intracranial haemorrhages in children treated with thrombolysis. •A faster access to neuroimaging and hyper-acute therapies was associated with the implementation of institutional protocols for the emergency management of pediatric stroke.

Reperfusion Therapies for Children With Arterial Ischemic Stroke

ABSTRACT

Modern hyperacute reperfusion therapies including intravenous thrombolysis and mechanical thrombectomy have transformed the management of arterial ischemic stroke (AIS) in adults. Multiple randomized clinical trials have demonstrated that these therapies enable remarkable improvements in clinical outcome for properly selected patients with AIS. Because pediatric patients were excluded from predicate clinical trials, there is a conspicuous lack of data to guide selection of therapies and inform age-adjusted and pathology-oriented treatment modifications for children. Specifically, technical guidance concerning treatment eligibility, drug dosing, and device implementation is lacking. This review aims to outline important features that differentiate pediatric AIS from adult AIS and provide practical strategies that will assist the stroke specialist with therapeutic decision making.

A Prospective Multicenter Registry on Feasibility, Safety, and Outcome of Endovascular Recanalization in Childhood Stroke (Save ChildS Pro)

Rationale: Early evidence for the benefit of mechanical thrombectomy (MT) in pediatric patients with intracranial large vessel occlusion has been shown in previous retrospective cohorts. Higher-level evidence is needed to overcome the limitations of these studies such as the lack of a control group and the retrospective design. Randomized trials will very likely not be feasible, and several open questions remain, for example, the impact of arteriopathic etiologies or a possible lower age limit for MT. Save ChildS Pro therefore aims to demonstrate the safety and effectiveness of MT in pediatric patients compared to the best medical management and intravenous thrombolysis.

Design: Save ChildS Pro is designed as a worldwide multicenter prospective registry comparing the safety and effectiveness of MT to the best medical care alone in the treatment of pediatric arterial ischemic stroke (AIS). It will include pediatric patients (<18 years) with symptomatic acute intracranial arterial occlusion who underwent either MT or best medical treatment including intravenous thrombolysis.

Outcomes: The primary endpoint of Save ChildS Pro is the modified Rankin Scale score at 90 days post-stroke. Secondary endpoints will comprise the decrease of the Pediatric National Institutes of Health Stroke Scale score from admission to discharge and rate of complications.

Discussion: Save ChildS Pro aims to provide high-level evidence for MT for pediatric patients with AIS, thereby improving functional outcome and quality of life and reducing the individual, societal, and economic burden of death and disability resulting from pediatric stroke.

Clinical Trial Registration: Save ChildS Pro is registered at the German Clinical Trials Registry (DRKS; identifier: DRKS00018960).

[Border areas of thrombectomy]

Mechanical thrombectomy (MT) has become the standard procedure in the treatment of patients with acute ischemic stroke (AIS) due to occlusion of a large proximal cerebral artery of the anterior circulation. Nevertheless, according to the current guidelines large patient collectives are still excluded from this highly effective treatment method. Therefore, this article gives an overview of possible extensions of the indications for treatment with MT. For example, patients in the extended time window with distal occlusions, with large infarct cores and also for very old (90+ years) or young (0-17 years) patients. Furthermore, we discuss recent developments in the interventional treatment of stroke, such as new triage concepts or the question whether an additional intravenous thrombolysis is necessary in patients with MT. We conclude with our own estimations for the discussed indications for treatment based on our clinical experience and the current literature.

Current treatment for childhood arterial ischaemic stroke

Paediatric arterial ischaemic stroke is an important cause of neurological morbidity in children, with consequences including motor disorders, intellectual impairment, and epilepsy. The causes of paediatric arterial ischaemic stroke are unique compared with those associated with stroke in adulthood. The past decade has seen substantial advances in paediatric stroke research and clinical care, but many unanswered questions and controversies remain. Shortage of prospective evidence for the use of recanalisation therapies in patients with paediatric stroke has resulted in little standardisation of disease management. Substantial time delays in diagnosis and treatment continue to challenge best possible care. In this Review, we highlight on some of the most pressing and productive aspects of research in the treatment of arterial ischaemic stroke in children, including epidemiology and cause, rehabilitation, secondary stroke prevention, and treatment updates focusing on advances in hyperacute therapies such as intravenous thrombolysis, mechanical thrombectomy, and critical care. Finally, we provide a future perspective for improving outcomes and quality of life for affected children and their families.

Letter-to-the Editor: Focal cerebral arteriopathy and acute ischaemic stroke in children: A diagnostic-therapeutical conundrum

Acute ischaemic stroke (AIS) in children is generally considered an up-to-date and controversial topic because its presents significant peculiarities. Focal cerebral arteriopathies (FCA) are a possible cause of AIS in children characterized by an unilateral lesion of the terminal internal cerebral artery (ICA) and proximal segment (M1) of middle cerebral artery (MCA), leading to subocclusion, occasionally with a typical "striate" pattern and a tendency to stability or regression at follow-up. It is unclear whether in FCA the basic lesion is an inflammatory or a dissective arterial pathology. Herein we report a small series of children (<16 yo) with AIS from a FCA who underwent mechanical thrombectomy (MT). We speculate on the angiographic findings suggesting an aetiology of the lesion, and on indications and limits of the currently available treatments.

Endovascular therapy for acute stroke in children: age and size technical limitations

Endovascular therapies for acute childhood stroke remain controversial and little evidence exists to determine the minimum age and size cut-off for thrombectomy in children. Despite this, an increasing number of reports suggest feasibility of thrombectomy in at least some children by experienced operators. When compared with adults, technical modifications may be necessary in children owing to differences in vessel sizes, tolerance of blood loss, safety of contrast and radiation exposure, and differing stroke etiologies. We review critical considerations for neurologists and neurointerventionalists when treating pediatric stroke with endovascular therapies. We discuss technical factors that may limit feasibility of endovascular therapy, including size of the femoral and cervicocerebral arteries, which contributes to vasospasm risk. The risk of femoral vasospasm can be assessed by comparing catheter outer diameter with estimated femoral artery size, which can be estimated based on the child's height. We review evidence supporting specific strategies to mitigate cervicocerebral arterial injury, including technique (stent retrieval vs direct aspiration) and device size selection. The importance of and strategies for minimizing blood loss, radiation exposure, and contrast administration are reviewed. Attention to these technical limitations is critical to delivering the safest possible care when thrombectomy is being considered for children with acute stroke.

Expanding indications for endovascular thrombectomy-how to leave no patient behind

Endovascular thrombectomy (EVT) has become standard of care for large vessel occlusion strokes but current guidelines exclude a large proportion of patients from this highly effective treatment. This review therefore focuses on expanding indications for EVT in several borderline indications such as patients in the extended time window, patients with extensive signs of infarction on admission imaging, elderly patients and patients with pre-existing deficits. It also discusses the current knowledge on intravenous thrombolysis as an adjunct to EVT and EVT as primary therapy for distal vessel occlusions, for tandem occlusions, for basilar artery occlusions and in pediatric patients. We provide clear recommendations based on current guidelines and further literature.

Mechanical Thrombectomy for Acute Ischemic Stroke: Considerations in Children

The use of mechanical thrombectomy for the treatment of acute childhood arterial ischemic stroke with large vessel occlusion is increasing, with mounting evidence for its feasibility and safety. Despite this emerging evidence, clear guidelines for patient selection, thrombectomy technique, and postprocedure care do not exist for the pediatric population. Due to unique features of stroke in children, neurologists and interventionalists must consider differences in patient size, anatomy, collateral vessels, imaging parameters, and expected outcomes that may impact appropriate patient selection and timing criteria. In addition, different causes of stroke and comorbidities in children must be considered and may alter the safety and efficacy of thrombectomy. To optimize the success of endovascular intervention in children, a multidisciplinary team should take into account these nuanced considerations when determining patient eligibility, developing a procedural approach, and formulating a postprocedure neurological monitoring and therapeutic plan.