Pediatric stroke: the importance of cerebral arteriopathy and vascular malformations

Closing the Gap in Pediatric Hemorrhagic Stroke: A Systematic Review

Pediatric hemorrhagic stroke (HS) accounts for a large proportion of childhood strokes, 1 of the top 10 causes of pediatric deaths. Morbidity and mortality lead to significant socio-economic and psychosocial burdens. To understand published data on recognizing and managing children with HS, we conducted a systematic review of the literature presented here. We searched PubMed, Embase, CINAHL and the Cochrane Library databases limited to English language and included 174 studies, most conducted in the USA (52%). Terminology used interchangeably for HS included intraparenchymal/intracranial hemorrhage, spontaneous ICH, and cerebrovascular accident (CVA). Key assessments informing prognosis and management included clinical scoring (Glasgow coma scale), and neuroimaging. HS etiologies reported were systemic coagulopathy (genetic, acquired pathologic, or iatrogenic), or focal cerebrovascular lesions (brain arteriovenous malformations, cavernous malformations, aneurysms, or tumor vascularity). Several scales were used to measure outcome: Glasgow outcome score (GOS), Kings outcome score for head injury (KOSCHI), modified Rankin scale (mRS) and pediatric stroke outcome measure (PSOM). Most studies described treatments of at-risk lesions. Few studies described neurocritical care management including raised ICP, seizures, vasospasm, or blood pressure. Predictors of poor outcome included ethnicity, comorbidity, location of bleed, and hematoma >2% of total brain volume. Motor and cognitive outcomes followed independent patterns. Few studies reported on cognitive outcomes, rehabilitation, and transition of care models. Interdisciplinary approach to managing HS is urgently needed, informed by larger cohort studies targeting key clinical question (eg development of a field-guide for the clinician managing patients with HS that is reproducible internationally).

Acute Hospital Management of Pediatric Stroke

The field of pediatric stroke has historically been hampered by limited evidence and small patient cohorts. However the landscape of childhood stroke is rapidly changing due in part to increasing awareness of the importance of pediatric stroke and the emergence of dedicated pediatric stroke centers, care pathways, and alert systems. Acute pediatric stroke management hinges on timely diagnosis confirmed by neuroimaging, appropriate consideration of recanalization therapies, implementation of neuroprotective measures, and attention to secondary prevention. Because pediatric stroke is highly heterogenous in etiology, management strategies must be individualized. Determining a child's underlying stroke etiology is essential to appropriately tailoring hyperacute stroke management and determining best approach to secondary prevention. Herein, we review the methods of recognition, diagnosis, management, current knowledge gaps and promising research for pediatric stroke.

Deep Phenotyping of T-Cells Derived From the Aneurysm Wall in a Pediatric Case of Subarachnoid Hemorrhage

Intracranial aneurysms (IAs) are very rare in children, and the characteristics of the T-cells in the IA wall are largely unknown. A comatose 7-years-old child was admitted to our center because of a subarachnoid hemorrhage due to a ruptured giant aneurysm of the right middle cerebral artery. Two days after the aneurysm clipping the patient was fully awake with left hemiparesis. T-cells from the IA wall and from peripheral blood of this patient were analyzed by multi-dimensional flow cytometry. Unbiased analysis, based on the use of FlowSOM clustering and dimensionality reduction technique UMAP, indicated that there was virtually no overlap between circulating and tissue-infiltrating T-cells. Thus, naïve T-cells and canonical memory T-cells were largely restricted to peripheral blood, while CD4^-CD8^-T-cells were strongly enriched in the IA wall. The unique CD4⁺, CD8⁺ and CD4^-CD8^-T-cell clusters from the IA wall expressed high levels of CCR5, Granzyme B and CD69, displaying thus characteristics of cytotoxic and tissue-resident effector cells. Low Ki67 expression indicated that they were nevertheless in a resting state. Among regulatory T-cell subsets, Eomes⁺Tr1-like cells were strongly enriched in the IA wall. Finally, analysis of cytokine producing capacities unveiled that the IA wall contained poly-functional T-cells, which expressed predominantly IFN-γ, TNF and IL-2. CD4⁺T-cells co-expressed also CD40L, and produced some IL-17, GM-CSF and IL-10. This report provides to our knowledge the first detailed characterization of the human T-cell compartment in the IA wall.

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.

Modeling Developmental Brain Diseases Using Human Pluripotent Stem Cells-Derived Brain Organoids - Progress and Perspective

Developmental brain diseases encompass a group of conditions resulting from genetic or environmental perturbations during early development. Despite the increased research attention in recent years following recognition of the prevalence of these diseases, there is still a significant lack of knowledge of their etiology and treatment options. The genetic and clinical heterogeneity of these diseases, in addition to the limitations of experimental animal models, contribute to this difficulty. In this regard, the advent of brain organoid technology has provided a new means to study the cause and progression of developmental brain diseases in vitro. Derived from human pluripotent stem cells, brain organoids have been shown to recapitulate key developmental milestones of the early human brain. Combined with technological advancements in genome editing, tissue engineering, electrophysiology, and multi-omics analysis, brain organoids have expanded the frontiers of human neurobiology, providing valuable insight into the cellular and molecular mechanisms of normal and pathological brain development. This review will summarize the current progress of applying brain organoids to model human developmental brain diseases and discuss the challenges that need to be overcome to further advance their utility.

Predictors of Neurological Outcome of Arterial Ischemic Stroke in Children

Stroke is an important cause of mortality and morbidity in children. The aim of the study was to evaluate long-term neurological outcome in children with arterial ischemic stroke (AIS) and explore predictive factors that affect poor outcome. Fifty-six patients aged between 1 month and 17 years who were treated at M. Iashvili Children's Central Hospital, Tbilisi, Georgia, with an onset of stroke from 2007 to 2017 were included. To explore predictive factors of outcome, the following data were collected: demographic characteristics, risk factors, he presenting signs, radiological features, and presence of stroke recurrence. Neurological status at discharge and long-term neurological outcome at least 1 year after stroke was evaluated according to Pediatric Stroke Outcome Measure subscale. The reported outcome after childhood stroke was variable with long-term neurological deficits in one-third of patients (30.4%). The neurological outcome was worse in males, in patients with multiple stroke episodes, and in those with infarctions involving a combination of cortical and subcortical areas. Pediatric AIS carries the risk of long-term morbidity, and neuroimaging has a predictive influence on outcome.

Intracerebral Nontraumatic Hemorrhagic Stroke in Children: Case Series and Literature Review

Pediatric stroke is an event caused by disturbance of cerebral circulation that occurs in individuals between 28 days and 18 years of age. Although an uncommon event, pediatric stroke still carries significant morbidity and mortality. Unlike adults, causes of pediatric stroke are various and include vascular, infectious, hematologic, neoplastic, and toxic etiologies. Clinical presentation of nontraumatic intracerebral hemorrhages in older children is similar to adults, however in neonates and infants signs and symptoms can be more subtle, especially with smaller hemorrhages. Management of nontraumatic intracerebral hemorrhage consists of stabilizing the patient, management of the hemorrhage itself, and reduction of the rebleeding risk. Even so, when child reaches a medical care, morbidity and mortality rates are still high. We described a case series of pediatric patients with intracerebral nontraumatic hemorrhagic stroke from different etiologies. Although increasingly recognized, such situations are still poorly described in children and our report offers a good overview on this topic.

Etiology of intracerebral hemorrhage in children: cohort study, systematic review, and meta-analysis

OBJECTIVE

Understanding the etiological spectrum of nontraumatic pediatric intracerebral hemorrhage (pICH) is key to the diagnostic workup and care pathway. The authors aimed to evaluate the etiological spectrum of diseases underlying pICH.

METHODS

Children treated at the authors' institution for a pICH were included in an inception cohort initiated in 2008 and retrospectively inclusive to 2000, which was analyzed in October 2019. They then conducted a systematic review of relevant articles in PubMed published between 1990 and 2019, identifying cohorts with pICH. Identified populations and patients from the authors' cohort were pooled in a multicategory meta-analysis.

RESULTS

A total of 243 children with pICH were analyzed in the cohort study. The final primary diagnosis was an intracranial vascular lesion in 190 patients (78.2%), a complication of a cardiac disease in 17 (7.0%), and a coagulation disorder in 14 (5.8%). Hematological and cardiological etiologies were disproportionately more frequent in children younger than 2 years (p < 0.001). The systematic review identified 1309 children in 23 relevant records pooled in the meta-analysis. Overall, there was significant heterogeneity. The dominant etiology was vascular lesion, with an aggregate prevalence of 0.59 (95% CI 0.45-0.64; p < 0.001, Q = 302.8, I2 = 92%). In 18 studies reporting a detailed etiological spectrum, arteriovenous malformation was the dominant etiology (68.3% [95% CI 64.2%-70.9%] of all vascular causes), followed by cavernoma (15.7% [95% CI 13.0%-18.2%]).

CONCLUSIONS

The most frequent etiology of pICH is brain arteriovenous malformation. The probability of an underlying vascular etiology increases with age, and, conversely, hematological and cardiac causes are dominant causes in children younger than 2 years.

CX3CR1-CCR2-dependent monocyte-microglial signaling modulates neurovascular leakage and acute injury in a mouse model of childhood stroke

Stroke is among the top 10 causes of death in children. The developmental stage of the brain is central to stroke pathophysiology. The incidence of childhood arterial ischemic stroke (CAIS) is lower than of perinatal arterial ischemic stroke but the rate of recurrence is strikingly high. Vascular inflammation is seen as major contributor to CAIS but the mechanisms that govern structural-functional basis of vascular abnormalities remain poorly understood. To identify the contribution of immune-neurovascular interactions to CAIS, we established stroke model in postnatal day 21 (P21) mice. We demonstrate acute functional deficits and histological injury and chronic MRI-identifiable injury, brain atrophy and marked derangements in the vascular network. In contrast to negligible albumin leakage and neutrophil infiltration following acute perinatal stroke, CAIS leads to significantly increased albumin leakage and neutrophil infiltration in injured regions of wild type mice and mice with functional CX3CR1-CCR2 receptors. In mice with dysfunctional CX3CR1-CCR2 signaling, extravascular albumin leakage is significantly attenuated, infiltration of injurious Ccr2⁺-monocytes essentially aborted, accumulation of Ly6G+ neutrophils reduced and acute injury attenuated. Unique identifiers of microglia and monocytes revealed phenotypic changes in each cell subtype of the monocyte lineage after CAIS. Taken together, CX3CR1-CCR2-dependent microglia-monocyte signaling contributes to cerebrovascular leakage, inflammation and CAIS injury.

Neurovascular Lesions in Pediatric Epilepsy

INTRODUCTION

Neurovascular lesions are rare and understudied in the pediatric population. Their initial presentation can range from seizures to focal neurologic deficits, as well as headaches. The goal of this study was to examine the clinical presentation and natural history of neurovascular lesions in children with epilepsy.

METHODS

We reviewed all pediatric epilepsy patients with neurovascular lesions diagnosed between 2006 and 2018 at the University of Alberta and the Stollery Children's Hospital, Edmonton, Canada. Initial clinical presentation and brain imaging, as well as long-term epilepsy and postsurgical outcome, were assessed.

RESULTS

Of the 14 patients, 10 patients had an initial presentation of focal seizures with impaired awareness, whereas 2 patients presented with headache, 1 presented with visual field defects as well as chronic headaches, and 1 with decreased level of consciousness. Seven patients had cavernous angiomas, 6 had arteriovenous malformation, and 1 patient had an arteriovenous fistula. Notably, all patients with cavernous angiomas and 4 of 6 patients with arteriovenous malformations presented with seizures. Among 9 of the 14 who underwent neurovascular corrective surgery, all 9 patients required long-term antiepileptic treatment of at least 1 antiepileptic drug for seizure control after the operation.

CONCLUSION

In this novel case series, we describe focal seizures as the initial presentation of pediatric neurovascular lesions. This clinical presentation appears to be independent of the type of neurovascular lesion. Furthermore, unlike our pediatric surgical patients with epilepsy due to other causes, seizure freedom following neurovascular surgery is limited, and patients require long-term antiepileptic treatment.

Characteristics and Treatment Outcome of Intracranial Aneurysms in Children and Adolescents

Objective

Intracranial aneurysms are not common in young age patients. We sought to find the characteristics of the intracranial aneurysms in patients under 20 years of age.

Methods

We reviewed 23 consecutive patients ≤20 years of age treated for their intracranial aneurysms during the period from 1995 to 2017. From medical records and imaging studies, we gathered data on age, sex, presentation, associated medical condition, location and characteristics of aneurysms, treatment and clinical outcomes.

Results

The patients’ ages ranged from 13 months to 20 years (median, 14 years). There were 16 males and seven females (male to female ratio, 2.3 : 1) with 31 aneurysms. Clinical presentations included sudden severe headache in 61%, followed by altered mentality in 17% and seizure in 17%. More than one-fourth patients had specific medical conditions related to the development of the cerebral aneurysms. The majority of aneurysms occurred in the anterior circulation (71%), and were saccular (71%). There were each three patients with false aneurysms (13%) and giant aneurysms (13%), and only one patient with multiple aneurysms (4%). We treated 22 patients : 21 aneurysms with the endovascular methods, three with open surgery, and one with combined treatment. Good functional outcome could be achieved in 86% during the follow-up period.

Conclusion

In this series, the young-age patients with intracranial aneurysms were characterized by male predominance, related specific medical conditions, low incidence of multiple aneurysms, high incidence of giant aneurysms and good functional outcome after treatment.

Features of Childhood Arterial Ischemic Stroke in China

Objective: The aim of this study was to identify the features and risk factors for arterial ischemic stroke (AIS) in children. Methods: We retrospectively analyzed the initial symptoms, clinical manifestations, risk factors, neuroradiological findings, and treatment data of 75 Chinese children aged between 1 month and 14 years (median 5.7 years) who were diagnosed with AIS in our hospital between 2013 and 2018. Results: Among these 75 cases of childhood AIS, 53 patients (70.67%) were male, and the male-to-female ratio was 2.41:1. A total of 55 cases (73.33%) had respiratory tract infection with fever. Seventy cases had lesions in the basal ganglia (46 left, 24 right). All patients were treated conservatively without thrombolytic therapy. Intravenous immunoglobulin treatment was given to children with fever and drowsiness. Conclusion: Infection was an important risk factor for children with AIS in China. Infection and thrombophilia risk factors were more likely to occur in isolation. The stroke lesions commonly occurred in the basal ganglia region.

Neuroimaging Abnormalities in Patients With Nontransfusion-dependent Thalassemia

Independence from regular transfusions is the hallmark of nontransfusion-dependent thalassemia (NTDT). However, the associated complications need anticipation and screening. One such complication is a hypercoagulable state predisposing to development of thrombosis. We evaluated children with NTDT >10 years of age for prevalence of neuroimaging abnormalities (NIA) and identified associated risk factors. In total, 29 patients were evaluated. Blood counts, serum ferritin, protein C, protein S, antithrombin III, brain magnetic resonance imaging, and angiography was done in all patients. Possible risk factors for thrombosis or cerebrovascular disease were analyzed for association with NIA. The median age was 14 (12 to 15) years. Fifty percent were splenctomized and 31.5% were transfusion naïve. Eleven patients (37.9%) had NIA: 6 with silent cerebral infarction (SCI); 2 with cerebral arteriopathy (CA) and 3 having both CA and SCI. Higher white blood cell (WBC) count was associated with NIA (P=0.034) [silent cerebral infarction (P=0.047) and cerebral arteriopathy (P=0.067)]. Presence of 7 or more risk factors had 4.5 times greater risk of a NIA, especially silent cerebral infarction (SCI) (P=0.03). We conclude that cerebral infarction and arteriopathy seem to start in late childhood. There is a need to develop strategies for preventing neurologic complications in NTDT similar to sickle cell disease.

Australian Clinical Consensus Guideline: The diagnosis and acute management of childhood stroke

Stroke is among the top 10 causes of death in children and survivors carry resulting disabilities for decades, at substantial cost to themselves and their families. Children are not currently able to access reperfusion therapies, due to limited evidence supporting safety and efficacy and long diagnostic delays. The Australian Clinical Consensus Guideline for the Diagnosis and Acute Management of Childhood Stroke was developed to minimize unwarranted variations in care and document best evidence on the risk factors, etiologies, and conditions mimicking stroke that differ from adults. Clinical questions were formulated to inform systematic database searches from 2007 to 2017, limited to English and pediatric studies. SIGN methodology and the National Health and Medical Research Council system were used to screen and classify the evidence. The Grades of Recommendation, Assessment, Development, and Evaluation system (GRADE) was used to grade evidence as strong or weak. The Guideline provides more than 60 evidence-based recommendations to assist prehospital and acute care clinicians in the rapid identification of childhood stroke, choice of initial investigation, to confirm diagnosis, determine etiology, selection of the most appropriate interventions to salvage brain at risk, and prevent recurrence. Recommendations include advice regarding the management of intracranial pressure and congenital heart disease. Implementation of the Guideline will require reorganization of prehospital and emergency care systems, including the development of regional stroke networks, pediatric Code Stroke, rapid magnetic resonance imaging and accreditation of primary pediatric stroke centers with the capacity to offer reperfusion therapies. The Guideline will allow auditing to benchmark timelines of care, access to acute interventions, and outcomes. It will also facilitate the development of an Australian childhood stroke registry, with data linkage to international registries, to allow for accurate data collection on stroke incidence, treatment, and outcomes.

Seasonal variation of stroke incidence in Wujin, a city in southeast China

OBJECTIVE

This study aimed to evaluate seasonal variations in stroke incidence in a city in southeast China.

METHODS

First-ever stroke in residents aged 20 or older in Wujin city was reported by local physicians between January 2006 and December 2007. All reported stroke cases were checked with the city-wide health insurance system. Fatal cases were checked with the household registry system. The annualized stroke incidences were calculated for each month and each season. The stroke incidence was compared among seasons, with spring as a reference.

RESULTS

Wujin city had an adult (≥20 y old) population of 1 278 020 in 2010. A total of 2319 stroke cases, 1217 male and 1102 female, were reported in 2006 and 2007. The raw annual incidence of stroke was 90.7/100 000 (95% CI: 82.1-94.5). Stroke incidence was highest in September (125.2/100 000; 95% CI = 109.4-139.3) and lowest in January (78.8/100 000; 95% CI = 69.1-93.2). Stroke incidence was highest in autumn (OR = 1.18, 95% CI: 1.05-1.32, P < .001, compared with spring). Autumn also had the highest incidences of ischemic stroke (OR = 1.22, 95% CI: 1.06-1.40).

CONCLUSIONS

Stroke incidence showed monthly and seasonal variations in southeast China. Autumn had the highest incidences of both ischemic stroke and cerebral hemorrhage.

Vascular Imaging Outcomes of Childhood Primary Angiitis of the Central Nervous System

BACKGROUND

Inflammation affecting cerebral blood vessels is a common cause of stroke in children. Arterial abnormalities on vascular imaging are an important risk factor for stroke recurrence. We aimed to describe the vascular imaging outcomes in children with primary angiitis of the central nervous system after 12 months and identify factors associated with vascular progression and stroke recurrence.

METHODS

We retrospectively analyzed clinical and neuroimaging data from the BrainWorks Registry of children with large-vessel primary angiitis of the central nervous system. Neuroimaging was collected at baseline and at least 12-month follow-up, and vascular outcome was categorized as improved, stable, or progressed based on comparison of magnetic resonance angiography. Univariate clinical and neuroimaging predictors were associated with outcome by Fisher exact test.

RESULTS

Our study consisted of 27 children; 20 male; median age was 7.92 years (range, two to 15 years). Twelve patients received steroids (44%). Median follow-up time was 16 months (range, 12 to 56 months). Vascular imaging outcome was categorized as improved in 37%, stable in 22%, and progressed in 41% of patients. Discordant progression, defined as progression and improvement occurring simultaneously across multiple vessels, was observed in 26%. Stroke recurred in 15%, occurring exclusively in the group with progression on follow-up imaging (P = 0.02).

CONCLUSIONS

After 12 months, 40% of children with primary angiitis of the central nervous system demonstrated progression on vascular imaging, without apparent clinical or angiographic predictors. Stroke recurrence was associated with vascular progression. Discordant progression is a newly described angiographic finding. Further studies are necessary to determine if this represents a unique characteristic of inflammatory arteriopathies.

Successful Manual Aspiration Thrombectomy in a Pediatric Patient

BACKGROUND

Timely recognition of stroke at major pediatric medical centers is improving, and although treatment guidelines for pediatric stroke exist, no extensive study establishing the efficacy of surgical or thrombolytic treatment has been completed. Extrapolation of adult guidelines to pediatric patients remains the mainstay of treatment in the absence of adequate information regarding safety and efficacy in children. Recent trials have demonstrated revascularization and clinical improvement after endovascular retrieval therapy in adults with acute large vessel occlusive stroke. Furthermore, successful mechanical thrombectomy using a variety of techniques has been documented in numerous children and adolescents.

PATIENT DESCRIPTION

We present a 15-year-old boy with altered mental status and left hemiparesis due to acute ischemic stroke secondary to blockage of the right internal carotid artery terminus, most likely precipitated by end-stage heart failure and cardiac embolism. Mechanical aspiration thrombectomy using the Penumbra aspiration catheter without any adjunct surgical equipment or thrombolytic therapy was used to remove thrombus and treat the patient's acute ischemic stroke. He experienced complete artery recanalization with a Thrombolysis in Cerebral Infarction (TICI) score of 2C after the procedure. He also exhibited an 8 point improvement in his pediatric National Institutes of Health Stroke Scale score within 24 hours.

CONCLUSIONS

Mechanical aspiration thrombectomy is commonly used in adult hospitals but infrequently employed in pediatric patients with arterial ischemic stroke. Given its efficacy in our patient, we encourage a larger systematic trial to evaluate the use of mechanical thrombectomy in pediatric patients with acute ischemic stroke.

A case of postvaricella cerebral angiopathy with a good outcome in a child

Cerebral vasculopathy is a serious but uncommon complication of varicella-zoster-virus (VZV) infection. Diagnosis is based on a recent history of VZV infection, signs and symptoms of transient ischemic attack or stroke, and vascular anomalies on neuroimaging. We report a case of postvaricella cerebral angiopathy in a 5-year-old child, who was admitted after three episodes of transient right hemiplegia, each one lasting a few minutes. He had contracted chicken pox, the month prior to admission. Brain magnetic resonance imaging showed hyperintense signals in the left lenticular and caudate nuclei, which can be considered to be a result of vasculopathy.

Risk factors and imaging characteristics of childhood stroke in china

There are scarce reports of childhood stroke from China. Our objective was to describe the clinical spectrum, risk factors, and imaging characteristics of childhood stroke in China. Using a hospital discharge database, children with stroke who were first admitted from 2002 to 2011 were retrospectively enrolled. We identified 478 first admissions with childhood stroke, including 229 cases of ischemic stroke and 249 hemorrhagic stroke. Boys accounted for more than 60% in all stroke types (62.2% for ischemic stroke, intracerebral hemorrhage for 66.2%). The leading cause was moyamoya for ischemic stroke and arteriovenous malformations for intracerebral hemorrhage. Hemiplegia and headache were the most common presenting features. Internal carotid artery and middle cerebral artery were the most involved arteries according to imaging examination in the ischemic stroke. A total of 8 patients died of intracerebral hemorrhage. The prevalence of hemorrhagic stroke was more than that of ischemic stroke. As Western countries, arteriopathy was the most common cause of childhood stroke.

Current concepts in pediatric stroke

Stroke is a relatively rare but rather significant cause of short- and long-term morbidity and mortality in children. It can be divided into three categories: arterial ischemic stroke (AIS), hemorrhagic stroke (HS) and cerebral sinovenous thrombosis (CSVT). This review focuses on AIS. The etiologies of pediatric AIS are diverse and different from those in adult stroke, chief among these being congenital heart disease, vasculopathies, hematological disorders and prothrombotic states. Additional factors might be related to the age group, ethnicity and geographic factors. Early recognition enables initiation of prompt therapy thereby reducing risk of further recurrence and complications.

Lumbar puncture requirement in acute hemiparesis: diagnosis of tuberculous meningitis after hemiparesis in a child

BACKGROUND

Infections are an important acquired cause of cerebral arteriopathy. Tuberculous (TB) meningitis leading to infectious cerebral vasculopathy is a rare cause of acute hemiparesis.

CASE REPORT

A 14-year-old male patient was examined after acute hemiparesis developing within 1 day. Neurological examination revealed total hemiplegia on the left side. Brain MRI findings showed bilateral focal T2-weighted signal hyperintensity in the subcortical and deep white matter regions. There were also areas of restricted diffusion in the right basal ganglia. Although the father had a history of pulmonary TB, the patient had not been given TB prophylaxis because of PPD negativity. At lumbar puncture, opening cerebrospinal fluid (CSF) pressure was 50 cm/H20, CSF protein 66.9 mg/dL, and glucose 54 mg/dL (concurrent blood glucose 93 mg/dL); 170 polymorphonuclear leukocytes per cubic millimeter were present in CSF. Following tests for TB, treatment was started immediately with four anti-TB drugs. TB PCR of CSF and acid-fast bacteria (AFB) staining in gastric aspirate were positive. At clinical follow-up, the patient was able to walk with support at the end of the first month.

CONCLUSION

Various infectious agents have been reported as causes of cerebral vasculopathy. TB, which affects a significant number of patients worldwide, should be kept in mind in terms of cerebral vascular complications. Lumbar puncture is essential in order to diagnose TB meningitis.

Strokes in children: a systematic review

CONTEXT

Pediatric strokes lead to significant morbidity and mortality. To date, no systematic review has been available to guide the initial diagnostic approach to pediatric stroke.

OBJECTIVE

The objective of this review was to elucidate the current data regarding etiologies of stroke in children and then develop an initial diagnostic evaluation for the pediatric patient presenting to the emergency department with a stroke.

DATA SOURCE

Using the PubMed engine, the MEDLINE database was searched using the Preferred Reporting Items in Systematic Reviews and Meta-Analyses guidelines.

STUDY SELECTION

The inclusion and exclusion criteria were established a priori. Studies must have extractable data regarding first strokes in pediatric patients with clear diagnostic categories.

DATA EXTRACTION

A standardized tool was developed to extract demographic data and stroke etiologies.

RESULTS

Twelve studies were found that met the inclusion criteria. From these studies, a total of 1455 children aged between 21 days and 20 years were available to assess the etiologies of stroke.

CONCLUSIONS

In pediatric patients, the etiologies of stroke are varied and differ for children with ischemic stroke versus hemorrhagic stroke. With the present systematic review, a guide to the initial evaluation of stroke is presented.

Surgery for a giant arteriovenous malformation without motor deterioration: preoperative transcranial magnetic stimulation in a non-cooperative patient

Transcranial magnetic stimulation (TMS) is a noninvasive activation method that is increasingly used for motor mapping. Preoperative functional mapping in vascular surgery is not routinely performed; however, in cases of high-grade arteriovenous malformations (AVMs), it could play a role in preoperative decision making. A 16-year-old male was suffering from a giant, right-sided insular, Spetzler-Martin Grade V AVM. This patient's history included 3 hemorrhagic strokes in the past 3 years, resulting in Medical Research Council Grade 2-3 (proximal) and 2-4 (distal) paresis of the left side of the body and hydrocephalus requiring a ventriculoperitoneal shunt. Preoperative TMS showed absent contralateral innervation of the remaining left-sided motor functions. Subsequently, the AVM was completely resected without any postoperative increase of the left-sided paresis. This case shows that TMS can support decision making in AVM treatment by mapping motor functions.

Complications of cerebral angiography in children younger than 3 years of age

OBJECT

The therapeutic potential for cerebral angiography (CA) in young children is expanding. However, its use in this patient population is limited by presumed higher complication rates among children. Therefore, to improve the accuracy of counseling of the parents/guardians of these patients and to identify modifiable risk factors, the authors evaluated complications after CA in young children.

METHODS

The authors reviewed data for 309 consecutive cerebral angiograms obtained in 87 children younger than 36 months of age from 2004 to 2010 at a single institution. They analyzed demographics, diagnosis, angiographic findings, and complications.

RESULTS

The patient population comprised 40 boys and 47 girls; mean age was 14.36 months (range 1-36 months) and mean weight was 10.8 kg (range 3.7-21.0 kg). For 292 of the 309 procedures, intraarterial chemotherapy was administered; the remaining 17 procedures were for vascular malformations, stroke, tumor embolization, and intracranial hemorrhage. The rate of neurological complications was 0.0%. The rate of nonneurological complications was 2.9%: 7 cases of contrast allergy or bronchospasm, 1 groin hematoma (body weight 7 kg), and 1 transient femoral artery occlusion (body weight 10.8 kg). The rate of radiographic complications was 1.3%: 1 case of transient asymptomatic intraarterial dissection and 3 cases of asymptomatic vasospasm. Postprocedural MRI was performed for 33.3% of patients with no evidence of ischemia. There were no delayed complications. Mean follow-up time was 16.6 months. No association was found between complications and age, duration of anesthesia, number of vessels catheterized, size of the sheath, or diagnostic versus interventional procedures. Despite a trend toward a higher rate of complications for patients who weighed less than 15 kg, this finding was not significant (p = 0.35).

CONCLUSIONS

The rate of complications for CA in young children is comparable to rates reported for older children and lower than rates reported for adults. When appropriately indicated, CA should not be omitted from the therapeutic strategy of children younger than 36 months of age.

The role of genetic risk factors in arterial ischemic stroke in pediatric and adult patients: a critical review

The incidence of arterial ischemic stroke (AIS) in childhood (about 2-13 per 100,000 children a year) is much lower than the incidence in the adult population. Still, adverse outcomes of acute brain ischemia in childhood include death (10% of AIS children), neurological sequel, epileptic seizures (over 50%) and recurrence (over 20%). The knowledge of childhood stroke etiopathogenesis is still insufficient and the diagnostic and therapeutic procedures--controversial. Risk factors for childhood stroke differ from those observed in adults due to differing exposure to external risk factors. The most frequently reported risk factors for pediatric ischemic stroke are cerebral arteriopathies and vascular malformations, cardiac diseases, infections, traumas and metabolic diseases. Because of its multifactorial etiology pediatric AIS probably has a multigenic inheritance pattern. The genetic susceptibility to AIS may be determined by specific polymorphic variants encoding markers of hemostasis regulation and they are some of the most important targets in searching for genetic determinants in pediatric AIS. The authors have reviewed the recent literature on risk factors of childhood ischemic stroke with the focus on genetic factors like polymorphisms of genes encoding coagulation factors II, V, VII and XIII, MTHFR, fibrinogen beta, and compared them with the results performed in adult patients.

Malignant paraganglioma presenting with hemorrhagic stroke in a child

Sympathetic paragangliomas are rare catecholamine-secreting tumors of extra-adrenal origin, and their diagnosis in children is even more infrequent. They usually manifest as hypertension, palpitations, headache, sweating, and pallor. Malignant paragangliomas are identified by the presence of metastasis. Hemorrhagic stroke in the pediatric population is a life-threatening condition with several etiologies. We report here the case of a 12-year-old boy with malignant sympathetic paraganglioma presenting with hemorrhagic stroke. Severe hypertension was found and the patient evolved into a coma. Brain computed tomography scan showed right thalamus hemorrhage with intraventricular extension. After clinical improvement, further investigation revealed elevated catecholamine and metanephrine levels, and 2 abdominal tumors were identified by computed tomography. Resection of both lesions was performed, and histologic findings were consistent with paraganglioma. Multiple metastatic involvement of bones and soft tissues appeared several years later. Genetic testing identified a mutation in succinate dehydrogenase subunit B gene, with paternal transmission. 131I-metaiodobenzylguanidine therapy was performed 3 times with no tumoral response. Our patient is alive, with adequate quality of life, 25 years after initial diagnosis. To our knowledge, this is the first pediatric case of paraganglioma presenting with hemorrhagic stroke. Intracerebral hemorrhage was probably caused by severe hypertension due to paraganglioma. Therefore, we expand the recognized clinical spectrum of the disease. Physicians evaluating children with hemorrhagic stroke, particularly if hypertension is a main symptom, should consider the possibility of catecholamine-secreting tumors. Metastatic disease is associated with succinate dehydrogenase subunit B mutations and, although some patients have poor prognosis, progression can be indolent.

Intracranial arteries in individuals with the elastin gene hemideletion of Williams syndrome

BACKGROUND AND PURPOSE

Williams syndrome, a rare genetic disorder with a striking neurobehavioral profile characterized by extreme sociability and impaired visuospatial construction abilities, is caused by a hemideletion that includes the elastin gene, resulting in frequent supravavular aortic stenosis and other stenotic arterial lesions. Strokes have been reported in Williams syndrome. Although the extracranial carotid artery has been studied in a sample of patients with Williams syndrome, proximal intracranial arteries have not.

MATERIALS AND METHODS

Using MRA, we studied the intracranial vessels in 27 participants: 14 patients with Williams syndrome (age range, 18-44 years; mean age, 27.3 ± 9.1; 43% women) and 13 healthy control participants with similar age and sex distribution (age range, 22-52 years; mean age, 33.4 ± 7.6; 46% women). All participants with Williams syndrome had hemideletions of the elastin gene. Blinded to group allocation or to any other clinical data, a neuroradiologist determined the presence of intracranial vascular changes in the 2 groups.

RESULTS

The Williams syndrome group and the healthy control group had similar patency of the proximal intracranial arteries, including the internal carotid and vertebral arteries; basilar artery; and stem and proximal branches of the anterior cerebral artery, MCA, and posterior cerebral arteries. The postcommunicating segment of the anterior cerebral artery was longer in the Williams syndrome group.

CONCLUSIONS

Despite the elastin haploinsufficiency, the proximal intracranial arteries in Williams syndrome preserve normal patency.

Complex chromosome rearrangement of 6p25.3->p23 and 12q24.32->qter in a child with moyamoya

A 7-year-old white girl presented with left hemiparesis and ischemic stroke secondary to moyamoya syndrome, a progressive cerebrovascular occlusive disorder of uncertain but likely multifactorial etiology. Past medical history revealed hearing loss and developmental delay/intellectual disability. Routine karyotype demonstrated extra chromosomal material on 6p. Single nucleotide polymorphism microarray revealed a previously unreported complex de novo genetic rearrangement involving subtelomeric segments on chromosomes 6p and 12q. The duplicated/deleted regions included several known OMIM-annotated genes. This novel phenotype and genotype provides information about a possible association of genomic copy number variation and moyamoya syndrome. Dosage-sensitive genes in the deleted and duplicated segments may be involved in aberrant vascular proliferation. Our case also emphasizes the importance of comprehensive evaluation of both developmental delay and congenital anomalies such as moyamoya.

Propranolol use in PHACE syndrome with cervical and intracranial arterial anomalies: collective experience in 32 infants

The objective of this retrospective study of patients evaluated between July 2008 and October 2011 in seven pediatric dermatology centers was to combine collective clinical experience using oral propranolol therapy in 32 infants with PHACE syndrome (Posterior fossa [brain malformations present at birth], Hemangioma [usually covering a large area of the skin of the head or neck >5 cm]; Arterial lesions [abnormalities of the blood vessels in the neck or head]; Cardiac abnormalities or aortic coarctation [abnormalities of the heart or blood vessels that are attached to the heart]; Eye abnormalities) with cervical or intracranial arterial anomalies. Patients were given an average daily dose of oral propranolol of 1.8 mg/kg divided two or three times per day for an average duration of 12.3 months. The main outcome measure was adverse neurologic events. Seven (22%) patients were categorized as being at higher risk for stroke, defined on magnetic resonance imaging as severe, long-segment narrowing or nonvisualization of major cerebral or cervical vessels without anatomic evidence of collateral circulation, often in the presence of concomitant cardiovascular comorbidities. Only one patient developed a change in neurologic status during propranolol treatment: mild right hemiparesis that remained static and improved while propranolol was continued. An additional three patients had worsening hemangioma ulceration or tissue necrosis during therapy. This is the largest report thus far of patients with PHACE syndrome treated with propranolol. Although no catastrophic neurologic events occurred, serious complications, particularly severe ulcerations, were seen in a minority of patients, and given the sample size, we cannot exclude the possibility that propranolol could augment the risk of stroke in this population. We propose radiologic criteria that may prove useful in defining PHACE patients as being at high or standard risk for stroke. We continue to advise caution in using systemic beta-blockers, particularly for children with vascular anomalies at higher risk for stroke. Use of the lowest possible dosage, slow dosage titration, three times per day dosing to minimize abrupt changes in blood pressure, and close follow-up, including neurologic consultation as needed, are recommended.

Ruptured dissecting vertebrobasilar aneurysm in childhood: what is the therapeutic strategy?

BACKGROUND/AIMS

Pediatric aneurysms are rare, accounting for 0.5-4.6% of all intracranial aneurysms. Dissecting vertebrobasilar aneurysms (DVBA) are more frequently observed among children than adults. Cases acutely presenting with subarachnoid hemorrhage need a prompt treatment because of the higher mortality related to untreated cases. Options for an active DVBA management depend on the features of the malformation and include endovascular and surgical approaches.

METHODS

We refer to an 8-year-old healthy female, who presented with a sudden severe headache and vomit, followed by a half-hour loss of consciousness. A CT scan revealed subarachnoid hemorrhage, and brain MR angiography showed a lesion with mass effect on bulbar structures, suggestive of an aneurysm of the vertebrobasilar junction. The intracranial angiography confirmed this diagnosis and showed a relevant revascularization coming from the anterior cerebral circulation.

RESULTS

Endovascular treatment was considered as a suitable option and occlusion of both vertebral arteries, saving the left posterior inferior cerebellar artery, was performed. No neurological deficits appeared after embolization, and the patient was clinically stable at 18 months of follow-up.

CONCLUSION

In the 'stent era', parent vessel deconstruction throughout endovascular balloon or coil occlusion could be considered in patients with a sound collateral circulation and when cerebellar hemisphere and encephalic trunk feeding is not compromised.

Neural bases of childhood speech disorders: lateralization and plasticity for speech functions during development

Current models of speech production in adults emphasize the crucial role played by the left perisylvian cortex, primary and pre-motor cortices, the basal ganglia, and the cerebellum for normal speech production. Whether similar brain-behaviour relationships and leftward cortical dominance are found in childhood remains unclear. Here we reviewed recent evidence linking motor speech disorders (apraxia of speech and dysarthria) and brain abnormalities in children and adolescents with developmental, progressive, or childhood-acquired conditions. We found no evidence that unilateral damage can result in apraxia of speech, or that left hemisphere lesions are more likely to result in dysarthria than lesion to the right. The few studies reporting on childhood apraxia of speech converged towards morphological, structural, metabolic or epileptic anomalies affecting the basal ganglia, perisylvian and rolandic cortices bilaterally. Persistent dysarthria, similarly, was commonly reported in individuals with syndromes and conditions affecting these same structures bilaterally. In conclusion, for the first time we provide evidence that longterm and severe childhood speech disorders result predominantly from bilateral disruption of the neural networks involved in speech production.

Paediatric Stroke: Review of the Literature and Possible Treatment Options, including Endovascular Approach

Stroke is among the top 10 causes of death in childhood. More than half of the surviving children have long-term neurological sequelae. Ischemic stroke (IS) includes arterial ischemic stroke and cerebral venous thrombosis with venous infarction. Haemorrhagic stroke (HS) includes intracerebral haematoma or subarachnoid haemorrhage. Risk factors for stroke are different in children and in adults. 10–30% of IS have no identified risk factors. However, multiple risk factors are recognizable in the majority of stroke in children; thus, a comprehensive diagnostic evaluation is crucial. Vascular abnormalities, such as arteriovenous malformations, aneurysms, vessel dissection, stenosis, and moyamoya disease, are frequently associated with both IS and HS and lead to high recurrence rates. Endovascular and surgical treatment options are sometimes indicated, performed on the basis of expert opinion, and extrapolated from the adult procedures. In the present paper, we review the recent literature and we discuss the treatment in five cases managed at our institutions.

Challenges in the diagnosis and treatment of pediatric stroke

Stroke in children is rarely due to traditional stroke risk factors such as hypertension and diabetes. Rather, stroke in this patient group typically results from the simultaneous occurrence of multiple stroke risk factors, the presence of which necessitates a thorough evaluation to determine the cause of this disorder. Several challenges exist in the care of children with stroke. Of note, recognition of pediatric stroke onset by parents and caregivers is often delayed, highlighting the need for increased awareness of and education regarding this condition. Moreover, various neurological conditions resemble stroke in pediatric patients and a definite diagnosis of this disorder requires MRI; adding to the diagnostic challenge, young children may need to be sedated to undergo acute MRI. Perhaps the most significant challenge is the need for clinical research studies focusing on pediatric stroke treatment, so as to allow evidence-based treatment decision-making. A final challenge is the standardization of outcome assessment after stroke for a wide range of ages and developmental levels. In this Review, we examine recent findings and diagnostic issues pertaining to both arterial ischemic stroke and hemorrhagic stroke in children.