Epilepsy panels in clinical practice: Yield, variants of uncertain significance, and treatment implications

OBJECTIVE

There has been increasing utilization of genetic testing for pediatric epilepsy in recent years. Little systematic data is available examining how practice changes have impacted testing yields, diagnostic pace, incidence of variants of uncertain significance (VUSs), or therapeutic management.

METHODS

A retrospective chart review was performed at Children's Hospital Colorado from February 2016 through February 2020. All patients under 18 years for whom an epilepsy gene panel was sent were included.

RESULTS

A total of 761 epilepsy gene panels were sent over the study period. During the study period, there was a 292% increase in the average number of panels sent per month. The time from seizure onset to panel result decreased over the study period from a median of 2.9 years to 0.7 years. Despite the increase in testing, the percentage of panels yielding a disease-causing result remained stable at 11-13%. A total of 90 disease-causing results were identified, > 75% of which provided guidance in management. Children were more likely to have a disease-causing result if they were < 3 years old at seizure onset (OR 4.4, p < 0.001), had neurodevelopmental concerns (OR 2.2, p = 0.002), or had a developmentally abnormal MRI (OR 3.8, p < 0.001). A total of 1417 VUSs were identified, equating to 15.7 VUSs per disease-causing result. Non-Hispanic white patients had a lower average number of VUSs than patients of all other races/ethnicities (1.7 vs 2.1, p < 0.001).

SIGNIFICANCE

Expansion in the volume of genetic testing corresponded to a decrease in the time from seizure onset to testing result. Diagnostic yield remained stable, resulting in an increase in the absolute number of disease-causing results annually-most of which have implications for management. However, there has also been an increase in total VUSs, which likely resulted in additional clinical time spent on VUS resolution.

Evaluation and Management of Deficiency of Adenosine Deaminase 2: An International Consensus Statement

Importance

Deficiency of adenosine deaminase 2 (DADA2) is a recessively inherited disease characterized by systemic vasculitis, early-onset stroke, bone marrow failure, and/or immunodeficiency affecting both children and adults. DADA2 is among the more common monogenic autoinflammatory diseases, with an estimate of more than 35 000 cases worldwide, but currently, there are no guidelines for diagnostic evaluation or management.

Objective

To review the available evidence and develop multidisciplinary consensus statements for the evaluation and management of DADA2.

Evidence Review

The DADA2 Consensus Committee developed research questions based on data collected from the International Meetings on DADA2 organized by the DADA2 Foundation in 2016, 2018, and 2020. A comprehensive literature review was performed for articles published prior to 2022. Thirty-two consensus statements were generated using a modified Delphi process, and evidence was graded using the Oxford Center for Evidence-Based Medicine Levels of Evidence.

Findings

The DADA2 Consensus Committee, comprising 3 patient representatives and 35 international experts from 18 countries, developed consensus statements for (1) diagnostic testing, (2) screening, (3) clinical and laboratory evaluation, and (4) management of DADA2 based on disease phenotype. Additional consensus statements related to the evaluation and treatment of individuals with DADA2 who are presymptomatic and carriers were generated. Areas with insufficient evidence were identified, and questions for future research were outlined.

Conclusions and Relevance

DADA2 is a potentially fatal disease that requires early diagnosis and treatment. By summarizing key evidence and expert opinions, these consensus statements provide a framework to facilitate diagnostic evaluation and management of DADA2.

Abstract 64: Screening For Psychosocial Health In Pediatric Stroke

Introduction: Impaired psychosocial health after stroke in adults is well established, with high prevalence of post-stroke anxiety and depression. Behavioral health following pediatric stroke is less well described. Early data suggest that pediatric stroke patients may experience higher rates of anxiety, depression, ADHD and PTSD. Early detection and treatment of behavioral health concerns can lead to improved psychosocial outcomes. However, screening measures to assess psychosocial functioning in pediatric stroke patients have not yet been explored.

Methods: This single-center retrospective cohort study (COMIRB 21-3536) examined behavioral health following pediatric stroke using the Pediatric Symptom Checklist (PSC-17) at an outpatient stroke clinic. The PSC-17 screens for a broad range of behavioral health symptoms including internalizing, externalizing, and attention concerns. This dataset included patients with a diagnosis of ischemic stroke, hemorrhagic stroke, CSVT, or periventricular venous infarction (PVI) between 0-18 years of age. Comparison data included all children seen at general outpatient pediatric appointments. Chi-square goodness of fit tests were performed to compare elevated PSC-17 score proportions in children with stroke to proportions found in the general pediatric population.

Results: We identified 65 pediatric stroke patients with a parent-reported PSC-17. Global, internalizing, and externalizing scores were higher among pediatric stroke patients compared to the general pediatric population, but there was no statistically significant difference in attention measures.

Conclusions: The PSC-17 identifies a higher prevalence of psychosocial health concerns among children who have experienced a stroke as compared to the general pediatric population. The PSC-17 may serve as an effective screening tool to identify pediatric stroke patients who may benefit from further psychosocial evaluation.

Thalamic Volume Loss Is Greater in Children Than in Adults Following Middle Cerebral Artery Territory Arterial Ischemic Stroke

Background: Younger stroke patients may suffer worse outcomes than older patients; however, the extent to which age at stroke impacts remote areas of the brain remains unclear. The objective of this study was to determine thalamic volume changes ipsilateral to middle cerebral artery territory strokes based on age at acute ischemic stroke onset. Methods: Acute ischemic stroke patients <9 years, 9-18 years, and >18 years old were retrospectively recruited from a large quaternary care system. Each subject underwent an acute (<72 hours from AIS) and chronic (>90 days) magnetic resonance imaging (MRI) scan. Manual thalamic segmentation was performed. Results: Younger and older children had significantly greater stroke-side thalamic volume loss compared to adults (48.2%, P = .022; 40.7%, P = .044, respectively). Conclusions: Stroke-side thalamic volumes decreased across the age spectrum but to a greater degree in pediatric patients. This observation can affect functional and cognitive outcomes post stroke and warrants further research.

Cerebral Arteriopathies of Childhood - Current Approaches

Up to more than half of previously healthy children presenting with their first arterial ischemic stroke have a cerebral arteriopathy. Cerebral arteriopathies during childhood can be congenital, reflecting abnormal vessel development, or acquired when caused by disruption of vascular homeostasis. Distinguishing different types of cerebral arteriopathies in children can be challenging but of great clinical value as they may dictate different disease and treatment courses, and clinical and radiologic outcomes. Furthermore, children with stroke due to a specific arteriopathy exhibit distinctive features when compared to those with stroke due to other causes or a different type of arteriopathy. These features become crucial in the management of pediatric stroke by choosing appropriate diagnostic and treatment strategies. The objective of this article is to provide the reader with a comprehensive up-to-date review of the classification, symptoms, diagnosis, treatment, and outcome of cerebral arteriopathies in children.

Stroke Recurrence in Children with Vertebral Artery Dissecting Aneurysm

BACKGROUND AND PURPOSE

Pediatric vertebral artery dissecting aneurysm is a subtype of vertebral artery dissection that can be challenging to diagnose and may be associated with stroke recurrence. This study examines the presenting features, clinical outcomes, and recurrence risk in a cohort of children with vertebral artery dissection, comparing those with aneurysms with those without.

MATERIALS AND METHODS

The medical records of children evaluated for vertebral artery dissection were retrospectively reviewed for neurologic presentation, treatment, stroke recurrence, and angiographic appearance of dissection. Cohort patients were categorized into 2 groups based on the presence or absence of a vertebral artery dissecting aneurysm and compared via the Fisher exact test, Student t test, and log-rank analyses. P < .05 was deemed statistically significant.

RESULTS

Thirty-two patients met the inclusion criteria, including 13 with vertebral artery dissecting aneurysms. Five cases of vertebral artery dissecting aneurysm were missed on the initial evaluation and diagnosed retrospectively. All patients received antiplatelet or anticoagulation therapy at the time of diagnosis. Children in the vertebral artery dissecting aneurysm group were more likely to present with stroke (P = .059), present at a younger age (P < .001), and have recurrent stroke (P < .001) compared with the group of children with vertebral artery dissection without an aneurysm. After surgery, no patients with vertebral artery dissecting aneurysm experienced recurrent stroke (P = .02).

CONCLUSIONS

Vertebral artery dissecting aneurysm is often missed on the initial diagnostic evaluation of children presenting with stroke. In children with vertebral artery dissection, the presence of an aneurysm is associated with stroke presentation at a younger age and stroke recurrence.

International Prevalence and Mechanisms of SARS-CoV-2 in Childhood Arterial Ischemic Stroke During the COVID-19 Pandemic

Background:

Data from the early pandemic revealed that 0.62% of children hospitalized with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had an acute arterial ischemic stroke (AIS). In a larger cohort from June 2020 to December 2020, we sought to determine whether our initial point estimate was stable as the pandemic continued and to understand radiographic and laboratory data that may clarify mechanisms of pediatric AIS in the setting of SARS-CoV-2.

Methods:

We surveyed international sites with pediatric stroke expertise to determine numbers of hospitalized SARS-CoV-2 patients <18 years, numbers of incident AIS cases among children (29 days to <18 years), frequency of SARS-CoV-2 testing for children with AIS, and numbers of childhood AIS cases positive for SARS-CoV-2 June 1 to December 31, 2020. Two stroke neurologists with 1 neuroradiologist determined whether SARS-CoV-2 was the main stroke risk factor, contributory, or incidental.

Results:

Sixty-one centers from 21 countries provided AIS data. Forty-eight centers (78.7%) provided SARS-CoV-2 hospitalization data. SARS-CoV-2 testing was performed in 335/373 acute AIS cases (89.8%) compared with 99/166 (59.6%) in March to May 2020, P<0.0001. Twenty-three of 335 AIS cases tested (6.9%) were positive for SARS-CoV-2 compared with 6/99 tested (6.1%) in March to May 2020, P=0.78. Of the 22 of 23 AIS cases with SARS-CoV-2 in whom we could collect additional data, SARS-CoV-2 was the main stroke risk factor in 6 (3 with arteritis/vasculitis, 3 with focal cerebral arteriopathy), a contributory factor in 13, and incidental in 3. Elevated inflammatory markers were common, occurring in 17 (77.3%). From centers with SARS-CoV-2 hospitalization data, of 7231 pediatric patients hospitalized with SARS-CoV-2, 23 had AIS (0.32%) compared with 6/971 (0.62%) from March to May 2020, P=0.14.

Conclusions:

The risk of AIS among children hospitalized with SARS-CoV-2 appeared stable compared with our earlier estimate. Among children in whom SARS-CoV-2 was considered the main stroke risk factor, inflammatory arteriopathies were the stroke mechanism.

Abstract TP3: Seizures As Stroke Mimics In Ultra-early Treatment On A Mobile Stroke Unit: A Pilot Study

Background: Stroke mimics are often difficult to distinguish from true ischemic and hemorrhagic cerebrovascular accidents, and present a challenge for appropriate delivery of rapid stroke treatment. This is particularly true in ultra-early stroke care with Mobile Stroke Units (MSU), which administer tPA in the field, within minutes of symptom onset. We sought to evaluate and characterize stroke mimics during prehospital care with an MSU at a Comprehensive Stroke Center.

Methods: The study compared patient and stroke characteristics, neurologic evaluation, and treatment between confirmed strokes and stroke mimics treated during a one-year pilot period on the MSU at a large urban medical center. Variables included patient demographics, NIHSS score, tPA administration, final diagnosis, and discharge disposition.

Results: Between Jan. 15, 2016 and Jan. 9, 2017, 47 patients received prehospital management on the MSU, and 44 were admitted to UC hospital and had an available final diagnosis. Of these, 12 (27%) were stroke mimics. Mimics were younger [median age 60 (IQR 54-71) years, mimics vs. 68 (IQR 60-77) years, strokes], and were more often female (58%, mimics vs. 47%, strokes). Initial NIHSS score was lower for confirmed strokes [median 3 (IQR 2-10) strokes, vs. 6 (IQR 4-12) mimics], but severe strokes with a NIHSS score >17, were more common in strokes (16%, strokes vs. 0%, mimics). Of mimics, 6 (50%) were seizures, 2 (17%) migraine, 2 (17%) conversion, 1 (8%) encephalopathy, and 1 (8%) delirium. Thirteen (30%) of all patients were treated with IV tPA on the MSU, of whom 4 (31%) were mimics. Of mimics given tPA, 2 were seizures, 1 migraine and 1 conversion. Mimics were more likely to be discharged to home (64%, mimics vs. 46%, strokes) while strokes more likely received rehabilitation (23%, strokes vs. 9%, mimics).

Conclusions: One third of patients treated on the MSU were stroke mimics, and among these the most common diagnosis was seizures. These results suggest vigilance is warranted for seizure, as well as further study of rapid EEG technologies to guide appropriate treatment for presentations that appear to be stroke, including antiepileptic drugs, in ultra-early MSU care of suspected CVA.

Abstract P841: The Impact of a Dedicated Pediatric Stroke Discharge Plan Upon Parent Preparedness for Clinic: Before and After the Start of Covid-19

Background: The Colorado Pediatric Stroke Program provides comprehensive, multidisciplinary care for pediatric stroke patients and their families. The team, which includes dedicated inpatient and outpatient nurse coordinators, instituted a plan to support the transition from the inpatient to outpatient setting.

Purpose: A survey was used to determine family preparedness for clinic and ease of scheduling their appointment. The data were collected before and after enacting remote scheduling and telehealth visits due to the COVID-19 pandemic.

Methods: Our team provided educational materials and an outpatient appointment time to families at time of discharge starting in 2019. In January 2020, the stroke clinic staff surveyed parents and guardians about their preparedness for clinic. Telehealth encounters were initiated due to COVID-19 in March 2020, with staff conducting RedCAP surveys by telephone. The survey measured several components of visit preparedness and satisfaction including: understanding of diagnosis, reason for referral prior to clinic visit, familiarity with the stroke team prior to clinic visit, and ease in appointment scheduling. We compared results before and after March 2020 via two-tailed chi-square analysis or two-tailed Fischer’s test.

Results: Prior to telehealth, families favorably reported responses with 92% (47/52) knowing the reason for referral, 86% (42/49) receiving educational material prior to clinic, and 84% (42/50) reporting familiarity with our team. All patients (50/50) reported that scheduling was easy. Only scheduling ease had a significant change during the pandemic, with 11% (2/11) of patients reporting difficulties with scheduling after starting telehealth ( P=0.03 ).

Conclusion: Childhood stroke is a disease with significant morbidity and mortality, requiring close follow-up care. Families report robust preparedness for clinic after the implementation of a comprehensive discharge plan. Although small numbers, remote scheduling and telehealth transition may present previously unseen barriers to scheduling during the pandemic. During abrupt changes in clinical operations additional scheduling resources may be needed to ensure continuity of care.

Abstract 56: Incidence of Large Vessel Occlusions in Children Who Present Within Extended Thrombectomy Treatment Window

Introduction: Mechanical thrombectomy (MT) should be considered in children with persistent deficits with large vessel occlusion (LVO), although the recognition and diagnosis of stroke is often delayed. With the recent extension of treatment windows to 24 hours in adult studies, more children may now be MT candidates. The aim of this project was to examine LVO incidence in childhood strokes that present within 24 hours of symptom onset.

Methods: Patients with clinical and radiographic confirmed stroke from 1995-2018 were identified via internal database search. Patients with last known normal < 24 hours and imaging within the MT time window (24 hours) were included for analysis. A pediatric neuroradiologist independently reviewed imaging to confirm presence/absence of LVO.

Results: Of 165 patients with childhood stroke, 60 (36.3%) had last known normal <24 hours and vessel imaging within the MT timeframe (table). Fourteen patients (8.5%) had an LVO; nine with internal carotid or M1 and five with M2 occlusions. Median time from symptom onset to imaging was 6.47 hours in LVO patients. Most common stroke etiologies with LVO were unilateral focal cerebral arteriopathy of childhood (5) and other (5). One of the LVO patients underwent MT.

Conclusions: At our institution, over 1/3 rd of patients presented within 24 hour of symptom onset with vascular imaging, and nearly 1/4 of those children (8.5% overall) had an LVO amenable to potential MT. While not all children with LVO will be MT candidates, this study shows that significant numbers of children present with LVO within the adult MT treatment window.

Pediatric Ischemic Stroke: An Infrequent Complication of SARS-CoV-2

OBJECTIVE

Severe complications of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) include arterial ischemic stroke (AIS) in adults and multisystem inflammatory syndrome in children. Whether stroke is a frequent complication of pediatric SARS-CoV-2 is unknown. This study aimed to determine the proportion of pediatric SARS-CoV-2 cases with ischemic stroke and the proportion of incident pediatric strokes with SARS-CoV-2 in the first 3 months of the pandemic in an international cohort.

METHODS

We surveyed 61 international sites with pediatric stroke expertise. Survey questions included: numbers of hospitalized pediatric (≤ 18 years) patients with SARS-CoV-2; numbers of incident neonatal and childhood ischemic strokes; frequency of SARS-CoV-2 testing for pediatric patients with stroke; and numbers of stroke cases positive for SARS-CoV-2 from March 1 to May 31, 2020.

RESULTS

Of 42 centers with SARS-CoV-2 hospitalization numbers, 8 of 971 (0.82%) pediatric patients with SARS-CoV-2 had ischemic strokes. Proportions of stroke cases positive for SARS-CoV-2 from March to May 2020 were: 1 of 108 with neonatal AIS (0.9%), 0 of 33 with neonatal cerebral sinovenous thrombosis (CSVT; 0%), 6 of 166 with childhood AIS (3.6%), and 1 of 54 with childhood CSVT (1.9%). However, only 30.5% of neonates and 60% of children with strokes were tested for SARS-CoV-2. Therefore, these proportions represent 2.9, 0, 6.1, and 3.0% of stroke cases tested for SARS-CoV-2. Seven of 8 patients with SARS-CoV-2 had additional established stroke risk factors.

INTERPRETATION

As in adults, pediatric stroke is an infrequent complication of SARS-CoV-2, and SARS-CoV-2 was detected in only 4.6% of pediatric patients with ischemic stroke tested for the virus. However, < 50% of strokes were tested. To understand the role of SARS-CoV-2 in pediatric stroke better, SARS-CoV-2 testing should be considered in pediatric patients with stroke as the pandemic continues. ANN NEUROL 2021;89:657-665.

Spectrum of cerebral arteriopathies in children with arterial ischemic stroke

OBJECTIVE

To determine that children with arterial ischemic stroke (AIS) due to an identifiable arteriopathy are distinct from those without arteriopathy and that each arteriopathy subtype has unique and recognizable clinical features.

METHODS

We report a large, observational, multicenter cohort of children with AIS, age 1 month to 18 years, enrolled in the International Pediatric Stroke Study from 2003 to 2014. Clinical and demographic differences were compared by use of the Fisher exact test, with linear step-up permutation min-p adjustment for multiple comparisons. Exploratory analyses were conducted to evaluate differences between cases of AIS with and without arteriopathy and between arteriopathy subtypes.

RESULTS

Of 2,127 children with AIS, 725 (34%) had arteriopathy (median age 7.45 years). Arteriopathy subtypes included dissection (27%), moyamoya (24.5%), focal cerebral arteriopathy-inflammatory subtype (FCA-i; 15%), diffuse cerebral vasculitis (15%), and nonspecific arteriopathy (18.5%). Children with arteriopathic AIS were more likely to present between 6 and 9 years of age (odds ratio [OR] 1.93, p = 0.029) with headache (OR 1.55, p = 0.023), multiple infarctions (OR 2.05, p < 0.001), sickle cell anemia (OR 2.9, p = 0.007), and head/neck trauma (OR 1.93, p = 0.018). Antithrombotic use and stroke recurrence were higher in children with arteriopathy. Among arteriopathy subtypes, dissection was associated with male sex, older age, headache, and anticoagulant use; FCA-i was associated with hemiparesis and single infarcts; moyamoya was associated with seizures and recurrent strokes; and vasculitis was associated with bilateral infarctions.

CONCLUSION

Specific clinical profiles are associated with cerebral arteriopathies in children with AIS. These observations may be helpful indicators in guiding early diagnosis and defining subgroups who may benefit most from future therapeutic trials.

Predicting Recovery and Outcome after Pediatric Stroke: Results from the International Pediatric Stroke Study

OBJECTIVE

To characterize predictors of recovery and outcome following pediatric arterial ischemic stroke, hypothesizing that age influences recovery after stroke.

METHODS

We studied children enrolled in the International Pediatric Stroke Study between January 1, 2003 and July 31, 2014 with 2-year follow-up after arterial ischemic stroke. Outcomes were defined at discharge by clinician grading and at 2 years by the Pediatric Stroke Outcome Measure. Demographic, clinical, and radiologic outcome predictors were examined. We defined changes in outcome from discharge to 2 years as recovery (improved outcome), emerging deficit (worse outcome), or no change.

RESULTS

Our population consisted of 587 patients, including 174 with neonatal stroke and 413 with childhood stroke, with recurrent stroke in 8.2% of childhood patients. Moderate to severe neurological impairment was present in 9.4% of neonates versus 48.8% of children at discharge compared to 8.0% versus 24.7% after 2 years. Predictors of poor outcome included age between 28 days and 1 year (compared to neonates, odds ratio [OR] = 3.58, p < 0.05), underlying chronic disorder (OR = 2.23, p < 0.05), and involvement of both small and large vascular territories (OR = 2.84, p < 0.05). Recovery patterns differed, with emerging deficits more common in children <1 year of age (p < 0.05).

INTERPRETATION

Outcomes after pediatric stroke are generally favorable, but moderate to severe neurological impairments are still common. Age between 28 days and 1 year appears to be a particularly vulnerable period. Understanding the timing and predictors of recovery will allow us to better counsel families and target therapies to improve outcomes after pediatric stroke. ANN NEUROL 2020;87:840-852.

Incidence and Clinical Outcomes of Streptococcus anginosus in Acute Complicated Sinusitis: A Pediatric Cohort

We conducted a retrospective cohort study of 160 hospitalized children admitted for acute complicated sinusitis and compared children with S anginosus-associated infection to children with other or no pathogens identified. The incidence of S anginosus-associated infections increased 12% per year, and infections with S anginosus are associated with increased morbidity.

Focal Cerebral Arteriopathy of Childhood: Novel Severity Score and Natural History

Background and Purpose- Focal cerebral arteriopathy (FCA)-a common cause of arterial ischemic stroke in previously healthy children-often progresses over days to weeks, increasing the risk of recurrent stroke. We developed a novel severity scoring system designed to quantify FCA progression and correlate with clinical outcomes. Methods- The VIPS study (Vascular Effects of Infection in Pediatric Stroke) prospectively enrolled 355 children with arterial ischemic stroke (2010-2014), including 41 with centrally confirmed FCA. Two neuroradiologists independently reviewed FCA cerebrovascular imaging, assigning a graded severity score of zero (no involvement) to 4 (occlusion) to individual arterial segments. The FCA severity score (FCASS) was the unweighted sum. In an iterative process, we modeled scores derived from different combinations of arterial segments to identify the model that optimized correlation with clinical outcome, simplicity, and reliability. Results- The optimal FCASS summed scores from 5 arterial segments: supraclinoid internal carotid artery, A1, A2, M1, and M2. The median (interquartile range) baseline FCASS was 4 (2-6). Of 33 children with follow-up imaging, the maximum FCASS (at any time point) was 7 (5-9). Twenty-four (73%) had FCA progression on follow-up with their maximum FCASS at a median of 8 (5-35.5) days poststroke; their median FCASS increase was 4 (2.5-6). FCASS did not correlate with recurrent arterial ischemic stroke. Maximum (but not baseline) FCASS correlated with 1-year pediatric stroke outcome measures ( P=0.037). Conclusions- Our novel scoring system for FCA severity correlates with neurological outcomes in the VIPS cohort and provides a tool for FCA treatment trials under development.

What is the Role of Mechanical Thrombectomy in Childhood Stroke?

BACKGROUND

Like adults, most children have lifelong morbidity after stroke. Revascularization therapies such as intravenous tissue plasminogen activator and mechanical thrombectomy may be options to decrease this morbidity in selected children, although currently there are no evidence-based recommendations to guide treatment. The utility and safety of mechanical thrombectomy in childhood stroke is unknown because of the lack of safety trials, case-controlled trials, and comprehensive retrospective studies. As such, the current rationale for the use of mechanical thrombectomy in childhood is based on extrapolation from adult experience, as well as consensus at individual institutions with many centers deciding care on a case-by-case basis. Nevertheless, the increasing use of recanalization therapies in appropriately selected adults with acute arterial ischemic stroke has led to an increase in consideration and use in childhood, and there are enough case reports and series, as well as experience, to suggest that some children with large vessel occlusion will likely benefit.

METHODS

We reviewed current literature regarding mechanical thrombectomy in childhood.

RESULTS

There are differences between pediatric and adult stroke which may impact safety, efficacy, and individual decision-making, including patient size, pathophysiology of stroke, deficit, experience, and lack of data regarding natural history of stroke in children.

CONCLUSIONS

Hospitals planning to perform mechanical thrombectomy in children should establish local procedures and guidelines for considering thrombectomy. In our experience, care is best provided through multidisciplinary teams including a pediatric vascular neurologist, neurointerventionalist with pediatric experience, and pediatric neurocritical care.

Delayed inhibition of tonic inhibition enhances functional recovery following experimental ischemic stroke

The current study focuses on the ability to improve cognitive function after stroke with interventions administered at delayed/chronic time points. In light of recent studies demonstrating delayed GABA antagonists improve motor function, we utilized electrophysiology, biochemistry and neurobehavioral methods to investigate the role of α5 GABAA receptors on hippocampal plasticity and functional recovery following ischemic stroke. Male C57Bl/6 mice were exposed to 45 min transient middle cerebral artery occlusion and analysis of synaptic and functional deficits performed 7 or 30 days after recovery. Our findings indicate that hippocampal long-term potentiation (LTP) is impaired 7 days after stroke and remain impaired for at least 30 days. We demonstrate that ex vivo administration of L655,708 reversed ischemia-induced plasticity deficits and importantly, in vivo administration at delayed time-points reversed stroke-induced memory deficits. Western blot analysis of hippocampal tissue reveals proteins responsible for GABA synthesis are upregulated (GAD65/67 and MAOB), increasing GABA in hippocampal interneurons 30 days after stroke. Thus, our data indicate that both synaptic plasticity and memory impairments observed after stroke are caused by excessive tonic GABA activity, making inhibition of specific GABA activity at delayed timepoints a potential therapeutic approach to improve functional recovery and reverse cognitive impairments after stroke.

Abstract TP505: Activity After Stroke in Children

Introduction: Childhood stroke is a devastating disease with lifelong morbidity that can last decades. Post-stroke exercise habits may be particularly important for long-term health and secondary stroke prevention in adulthood. We hypothesized that children with stroke have decreased activity as compared to age and gender matched healthy controls.

Methods: We enrolled 15 children from our IRB approved institutional stroke database and 15 controls to participate in a two-week study of daily activity (mean age=13 years, 80% female). Participants were asked to wear bilateral wireless ankle accelerometers with Bluetooth transmission to a smartphone around each ankle 8 hours or more a day for 14 days. Demographic data, activity patterns (i.e., total walking time, time spent sedentary, average walking speed), and compliance were recorded. Stroke size was measured by neuroradiologists as a percentage of total brain volume. We then compared the percentage of time sedentary between cases and controls via two-tailed t-test, as well as performed a regression analysis to determine the impact of stroke size upon activity levels.

Results: Children with stroke wore monitors an average of 10 of the 14 requested days for an average of 9.6 hours each day, as compared to controls who averaged 9 of the 14 requested days for an average of 10.6 hours each day. As expected, children with stroke show a slightly slower walking speed of 1.17 meters per second as compared to controls at 1.2 meters per second. While children with stroke walked a similar number of hours per day as the control group (1.42 for cases vs 1.48 for controls), both groups were sedentary a great percentage of time (85% vs 86% respectively, P=0.38). Patients with larger strokes did not record less activity than peers with smaller strokes (P=0.823).

Conclusion: Activity levels in children after stroke are comparable to their age and gender-matched peers, although less than ideal in both groups. In addition, stroke size did not have an impact upon activity levels in children with stroke. These findings suggest activity studies are feasible in this population, and will need to be confirmed in larger prospective studies. Low overall levels of activity may still represent an opportunity for intervention in this population.

Age-associated hippocampal volume changes in childhood arterial ischemic stroke

PURPOSE

Recent evidence suggests that recovery from secondary neurodegeneration following arterial ischemic stroke (AIS) may be related to age at injury and site of occlusion. We conducted a study of hippocampal volume (HCV) in a cohort of pediatric patients with middle cerebral artery (MCA) territory AIS to determine whether HCV would be preserved in younger children as compared to older children.

METHODS

This single-center, HIPAA-compliant retrospective study was approved by the institutional review board. The medical records of 149 children treated for AIS between 2000 and 2016 were reviewed for inclusion criteria: unilateral MCA territory AIS and availability of high-resolution T1-weighted MR imaging at both acute and chronic time periods. Manual segmentation was utilized to measure stroke-side HCV, contralateral HCV, hemispheric volumes, and stroke volume on each scan. To correct for variable brain size, HCV measurements were ratio normalized. Patients were divided into two age-at-stroke groups: younger (30 days-9 years old) and older (> 9-18 years old). Analysis was performed using Fisher's test or Student's t test.

RESULTS

The MR imaging of 19 children (9 younger, 10 older) was analyzed. At follow-up, the average stroke-side HCV increased by 10.9% in the younger group and decreased by 6.3% in the older group (P = 0.010); this between-group difference remained significant even when ratio normalized (P = 0.003). The total brain volume-adjusted acute stroke size between groups was not statistically different (P = 0.649).

CONCLUSIONS

In children with AIS, younger age is associated with the relative preservation of HCV, which could reflect differences in age-related plasticity.

Abstract WP383: Neuropsychological Outcomes Following Pediatric Cerebral Sinovenous Thrombosis

Introduction: Few research studies have investigated neuropsychological domains beyond IQ in pediatric cerebral sinovenous thrombosis (CSVT). Additionally, prior studies have contained small sample sizes making generalization of results difficult. This study investigates a broad set of neuropsychological domains in pediatric CSVT and identifies predictors of poor outcomes.

Hypothesis: Children with CSVT were predicted to have worse cognitive outcomes compared to the normative sample. Earlier age at CSVT and the presence of acute symptoms associated with CNS dysfunction (e.g., altered mental status, aphasia, ataxia, seizure, and hemiparesis) were also hypothesized to predict worse long-term outcomes.

Methods: 20 children (mean age = 15.6 years) who suffered a CSVT during childhood (range = 3.6 to 18.0 years) participated in this study. Children completed a comprehensive neuropsychological battery and parents completed several standardized behavioral questionnaires. Testing was completed at least 6 months post-CSVT. Data were analyzed using one-sample t -tests and ANOVA.

Results: Children with CSVT had significantly greater problems on measures of mood, behavior, visual-motor integration, and processing speed compared to the normative sample (all p -values < 0.05). There were also trends for children with CSVT to have poorer performance on measures of confrontation naming ( p = 0.051), sentence repetition ( p = 0.064), and metacognition ( p = 0.057). Age at the time of CSVT was a significant predictor, such that older age at CSVT was associated with poorer single word reading and poorer visual-motor integration, but higher adaptive functioning. In these preliminary findings, acute symptoms associated with CNS dysfunction did not significantly predict outcomes.

Conclusions: To our knowledge, these findings represent the largest study to date investigating a broad set of neuropsychological domains following pediatric CSVT. This population demonstrated weaknesses in visual-motor integration and processing speed compared to the normative sample. Additionally, these children exhibited more mood and behavior symptoms, supporting the need for careful psychological follow-up in this vulnerable population.

Clinical and Imaging Characteristics of Arteriopathy Subtypes in Children with Arterial Ischemic Stroke: Results of the VIPS Study

BACKGROUND AND PURPOSE

Childhood arteriopathies are rare but heterogenous, and difficult to diagnose and classify, especially by nonexperts. We quantified clinical and imaging characteristics associated with childhood arteriopathy subtypes to facilitate their diagnosis and classification in research and clinical settings.

MATERIALS AND METHODS

The Vascular Effects of Infection in Pediatric Stroke (VIPS) study prospectively enrolled 355 children with arterial ischemic stroke (2010-2014). A central team of experts reviewed all data to diagnose childhood arteriopathy and classify subtypes, including arterial dissection and focal cerebral arteriopathy-inflammatory type, which includes transient cerebral arteriopathy, Moyamoya disease, and diffuse/multifocal vasculitis. Only children whose stroke etiology could be conclusively diagnosed were included in these analyses. We constructed logistic regression models to identify characteristics associated with each arteriopathy subtype.

RESULTS

Among 127 children with definite arteriopathy, the arteriopathy subtype could not be classified in 18 (14%). Moyamoya disease (n = 34) occurred mostly in children younger than 8 years of age; focal cerebral arteriopathy-inflammatory type (n = 25), in children 8-15 years of age; and dissection (n = 26), at all ages. Vertigo at stroke presentation was common in dissection. Dissection affected the cervical arteries, while Moyamoya disease involved the supraclinoid internal carotid arteries. A banded appearance of the M1 segment of the middle cerebral artery was pathognomonic of focal cerebral arteriopathy-inflammatory type but was present in <25% of patients with focal cerebral arteriopathy-inflammatory type; a small lenticulostriate distribution infarct was a more common predictor of focal cerebral arteriopathy-inflammatory type, present in 76%. It remained difficult to distinguish focal cerebral arteriopathy-inflammatory type from intracranial dissection of the anterior circulation. We observed only secondary forms of diffuse/multifocal vasculitis, mostly due to meningitis.

CONCLUSIONS

Childhood arteriopathy subtypes have some typical features that aid diagnosis. Better imaging methods, including vessel wall imaging, are needed for improved classification of focal cerebral arteriopathy of childhood.

Long-Term Outcomes and Risk Factors Associated With Acute Encephalitis in Children

BACKGROUND

Factors associated with poor outcomes of children with encephalitis are not well known. We sought to determine whether electroencephalography (EEG) findings, magnetic resonance imaging (MRI) abnormalities, or the presence of seizures at presentation were associated with poor outcomes.

METHODS

A retrospective review of patients aged 0 to 21 years who met criteria for a diagnosis of encephalitis admitted between 2000 and 2010 was conducted. Parents of eligible children were contacted and completed 2 questionnaires that assessed current physical and emotional quality of life and neurological deficits at least 1 year after discharge.

RESULTS

During the study period, we identified 142 patients with an International Classification of Diseases 9th Revision diagnosis of meningitis, meningoencephalitis, or encephalitis. Of these patients, 114 met criteria for a diagnosis of encephalitis, and 76 of these patients (representing 77 hospitalizations) had complete data available. Forty-nine (64%) patients were available for follow-up. Patients admitted to the intensive care unit were more likely to have abnormal EEG results (P = .001). The presence of seizures on admission was associated with ongoing seizure disorder at follow-up. One or more years after hospitalization, 78% of the patients had persistent symptoms, including 35% with seizures. Four (5%) of the patients died. Abnormal MRI findings and the number of abnormal findings on initial presentation were associated with lower quality-of-life scores.

CONCLUSIONS

Encephalitis leads to significant morbidity and death, and incomplete recovery is achieved in the majority of hospitalized patients. Abnormal EEG results were found more frequently in critically ill children, patients with abnormal MRI results had lower quality-of-life scores on follow-up, and the presence of seizures on admission was associated with ongoing seizure disorder and lower physical quality-of-life scores.

Abstract 169: Clinical and Imaging Biomarkers of Childhood Arteriopathy: Results of the Vascular effects of Infection in Pediatric Stroke (VIPS) Study

Introduction: Childhood cerebral arteriopathies are heterogeneous and difficult to classify. Our goal was to identify clinical and imaging biomarkers associated with subtypes of childhood arteriopathy in order to facilitate their diagnosis and classification in both research and clinical settings.

Methods: From 2009-2014, the VIPS study enrolled 355 children (age 29d-18y) with arterial ischemic stroke. A neuroradiologist and pediatric vascular neurologist independently reviewed vascular imaging and clinical data to diagnose arteriopathy (none, possible, definite), and then classify arteriopathy subtype: arterial dissection, transient cerebral arteriopathy (TCA), moyamoya, and secondary vasculitis. Disagreements were resolved through discussion by a panel of two neuroradiologists and two pediatric vascular neurologists. We constructed multivariable logistic regression models to identify characteristics independently associated with each subtype.

Results: Of 127 cases with definite arteriopathy, 109 received a single arteriopathy subtype diagnosis (26 dissection, 25 TCA, 34 moyamoya, 15 secondary vasculitis, and 9 “other”), while 18 were of indeterminate subtype. There were no cases of primary vasculitis. Independent predictors of arteriopathy subtype are shown (Table). The association between black race and moyamoya is explained by sickle cell anemia. A banding pattern on the vascular imaging was pathognomonic of TCA. Moyamoya and vasculitis secondary to meningitis had similar distal internal carotid artery abnormalities, but lenticulostriate collaterals suggested moyamoya, and a decreased level of consciousness predicted secondary vasculitis.

Conclusions: The different subtypes of childhood arteriopathies are associated with typical clinical, parenchymal and vascular imaging features that can help narrow the differential diagnosis in pediatric stroke patients with vascular abnormalities.

Abstract TP405: Psychological Outcomes After Childhood Arterial Ischemic Stroke

Introduction: Previous research has broadly documented that emotional and behavioral difficulties are seen after pediatric stroke; however, global ratings are generally reported without comparison to age-based norms. Additionally, little is known about the discrete symptomatology exhibited by these children. Thus, the goal of the present study was to evaluate specific psychological symptoms following childhood arterial ischemic stroke (AIS).

Hypothesis: Children with AIS were predicted to have increased difficulties in both internalizing and externalizing symptoms compared to the normative sample. Age at AIS was anticipated to influence the presence of psychological symptoms, with internalizing symptoms occurring at higher levels when the AIS occurred at a later age.

Methods: Participants were children ( n = 50, mean age = 12.1 years) who suffered an AIS during childhood (range = 1 month to 17.1 years). Parents completed the Child Behavior Checklist at least 10 months post-AIS (mean = 4.1 years). Children were divided into groups by age at AIS: early (<6 years), middle (6-10 years), or late (>10 years) childhood. Data were analyzed using one-sample t -tests and ANOVA.

Results: Children with AIS had significantly greater problems on the following DSM-oriented scales compared to the normative sample (all p -values < 0.01): Affective Problems, Anxiety Problems, Somatic Problems, Oppositional Defiant Problems, and Conduct Problems. There was a significant age-at-AIS effect on the Anxiety Problems subscale, F (2, 49) = 3.31, p = 0.05, such that the early childhood group had significantly higher levels of anxiety compared to the late childhood group.

Conclusions: Increased internalizing and externalizing symptoms were seen in children with AIS compared to the normative sample, and a higher percentage of children with AIS exceeded a clinically significant threshold in each domain. Contrary to expectations, children who had AIS at an earlier age showed greater number of anxiety symptoms relative to same-age peers. Possible mechanisms for the latter may include changes in family dynamics when young children suffer a neurological injury. These results support the need for careful psychological follow-up in this vulnerable population.

Moyamoya in a Patient with Smith-Magenis Syndrome

Occurrence of moyamoya syndrome in a patient with Smith-Magenis syndrome (SMS) has previously been reported once in a 10-year-old Asian female. We report a second case of moyamoya in a patient with SMS, in a now 25-year-old Asian female diagnosed with both conditions as a child. In addition to describing her medical and surgical history, we provide a detailed report of her omental transposition, in which the omental circulation was anastomosed to the superior thyroid artery and external jugular vein. To our knowledge, this is the first report of omental transposition for moyamoya in which omental vessels are anastomosed to vessels in the neck, as well as the second report of moyamoya in a patient with SMS.

Inter-Rater Reliability of the CASCADE Criteria: Challenges in Classifying Arteriopathies

BACKGROUND AND PURPOSE

There are limited data about the reliability of subtype classification in childhood arterial ischemic stroke, an issue that prompted the IPSS (International Pediatric Stroke Study) to develop the CASCADE criteria (Childhood AIS Standardized Classification and Diagnostic Evaluation). Our purpose was to determine the CASCADE criteria's reliability in a population of children with stroke.

METHODS

Eight raters from the IPSS reviewed neuroimaging and clinical records of 64 cases (16 cases each) randomly selected from a prospectively collected cohort of 113 children with arterial ischemic stroke and classified them using the CASCADE criteria. Clinical data abstracted included history of present illness, risk factors, and acute imaging. Agreement among raters was measured by unweighted κ statistic.

RESULTS

The CASCADE criteria demonstrated a moderate inter-rater reliability, with an overall κ statistic of 0.53 (95% confidence interval [CI]=0.39-0.67). Cardioembolic and bilateral cerebral arteriopathy subtypes had much higher agreement (κ=0.84; 95% CI=0.70-0.99; and κ=0.90; 95% CI=0.71-1.00, respectively) than cases of aortic/cervical arteriopathy (κ=0.36; 95% CI=0.01-0.71), unilateral focal cerebral arteriopathy of childhood (FCA; κ=0.49; 95% CI=0.23-0.76), and small vessel arteriopathy of childhood (κ=-0.012; 95% CI=-0.04 to 0.01).

CONCLUSIONS

The CASCADE criteria have moderate reliability when used by trained and experienced raters, which suggests that it can be used for classification in multicenter pediatric stroke studies. However, the moderate reliability of the arteriopathic subtypes suggests that further refinement is needed for defining subtypes. Such revisions may reduce the variability in the literature describing risk factors, recurrence, and outcomes associated with childhood arteriopathy.

Inflammatory Biomarkers in Childhood Arterial Ischemic Stroke: Correlates of Stroke Cause and Recurrence

BACKGROUND AND PURPOSE

Among children with arterial ischemic stroke (AIS), those with arteriopathy have the highest recurrence risk. We hypothesized that arteriopathy progression is an inflammatory process and that inflammatory biomarkers would predict recurrent AIS.

METHODS

In an international study of childhood AIS, we selected cases classified into 1 of the 3 most common childhood AIS causes: definite arteriopathic (n=103), cardioembolic (n=55), or idiopathic (n=78). We measured serum concentrations of high-sensitivity C-reactive protein, serum amyloid A, myeloperoxidase, and tumor necrosis factor-α. We used linear regression to compare analyte concentrations across the subtypes and Cox proportional hazards models to determine predictors of recurrent AIS.

RESULTS

Median age at index stroke was 8.2 years (interquartile range, 3.6-14.3); serum samples were collected at median 5.5 days post stroke (interquartile range, 3-10 days). In adjusted models (including age, infarct volume, and time to sample collection) with idiopathic as the reference, the cardioembolic (but not arteriopathic) group had higher concentrations of high-sensitivity C-reactive protein and myeloperoxidase, whereas both cardioembolic and arteriopathic groups had higher serum amyloid A. In the arteriopathic (but not cardioembolic) group, higher high-sensitivity C-reactive protein and serum amyloid A predicted recurrent AIS. Children with progressive arteriopathies on follow-up imaging had higher recurrence rates, and a trend toward higher high-sensitivity C-reactive protein and serum amyloid A, compared with children with stable or improved arteriopathies.

CONCLUSIONS

Among children with AIS, specific inflammatory biomarkers correlate with cause and-in the arteriopathy group-risk of stroke recurrence. Interventions targeting inflammation should be considered for pediatric secondary stroke prevention trials.

Pediatric Cortical Vein Thrombosis: Frequency and Association With Venous Infarction

BACKGROUND AND PURPOSE

Cortical vein thrombosis (CVT) is an uncommon site of involvement in cerebral sinovenous thrombosis. Few reports have described pediatric CVT, and none has differentiated its unique attributes. This study assessed the clinical features and radiographic outcome of a cohort of children with cerebral sinovenous thrombosis, comparing those with CVT to those without CVT.

METHODS

Children diagnosed with cerebral sinovenous thrombosis were retrospectively reviewed and separated into 2 groups based on the presence or absence of cortical vein involvement.

RESULTS

Fifty patients met inclusion criteria, including 12 with CVT. The CVT group was more likely to present with seizure (P=0.0271), altered mental status (P=0.0271), and a family history of clotting disorder (P=0.0477). Acute imaging of the CVT group more commonly demonstrated concurrent superior sagittal sinus thrombosis (P=0.0024), parenchymal hemorrhage (P=0.0141), and restricted diffusion (P<0.0001). At follow-up, the CVT group more commonly showed headache, seizure, and focal neurological deficit (P=0.0449), and venous infarction (P=0.0007).

CONCLUSIONS

In our cohort, CVT was significantly associated with seizures at presentation, hemorrhage and restricted diffusion on acute imaging, as well as neurological disability and venous infarction at follow-up. Involvement of cortical veins in cerebral sinovenous thrombosis is associated with an increased risk of infarction and adverse outcome in children.

Preparing for a "Pediatric Stroke Alert"

BACKGROUND

Childhood arterial ischemic stroke is an important cause of morbidity and mortality in children. Hyperacute treatment strategies remain controversial and challenging, especially in the setting of increasingly proven medical and endovascular options in adults. Although national and international pediatric guidelines have given initial direction about acute therapy and management, pediatric centers have traditionally lacked the infrastructure to triage, diagnose, and treat childhood arterial ischemic stroke quickly.

METHODS

In the past 10 years, researchers in the International Pediatric Stroke Study and Thrombolysis in Pediatric Stroke study have initiated early strategies for establishing pediatric specific stroke alerts.

RESULTS

We review the rationale, process and components necessary for establishing a pediatric stroke alert.

CONCLUSION

Development of pediatric stroke protocols and pathways, with evidence-based acute management strategies and supportive care where possible, facilitates the evaluation, management, and treatment of an acute pediatric stroke.

Guidelines for Urgent Management of Stroke in Children

Stroke in children carries lasting morbidity. Once recognized, it is important to evaluate and treat children with acute stroke efficiently and accurately. All children should receive neuroprotective measures. It is reasonable to consider treatment with advanced thrombolytic and endovascular agents. Delivery of such care requires purposeful institutional planning and organization in pediatric acute care centers. Primary stroke centers established for adults provide an example of the multidisciplinary approach that can be applied to the evaluation and treatment of children who present with acute stroke. The organizational infrastructure of these centers can be employed and adapted for treatment of children with acute stroke. It is likely that care for children with acute stroke can best be delivered by regional pediatric primary stroke centers dedicated to the care of children with pediatric stroke.

Abstract WMP104: Pediatric Cortical Vein Thrombosis: Frequency and Association With Venous Infarction

Introduction: Cortical vein thrombosis (CVT) is an uncommon site of involvement in cerebral sinovenous thrombosis (CSVT). Few reports have described pediatric CVT, and none have described its unique features. The aim of our study was to evaluate the clinical and radiographic features of a cohort of children with CSVT, comparing those with CVT to those without CVT.

Hypothesis: Children with CVT are more likely to experience acute restricted diffusion and chronic venous infarction, as compared to those without CVT.

Methods: Children diagnosed with CSVT from 2006 to 2014 were enrolled in a prospective cohort study at a single tertiary care center. Inclusion criteria comprised confirmation of CSVT on acute imaging with MRI/MRV or CTV, and availability of follow-up imaging at subacute and chronic time periods. Patients were separated into two groups: those with CVT (CVT group) and those without (non-CVT group). Patient demographics, clinical presentation, and imaging findings were collected and analyzed using a two-tailed Fisher's exact test. Scans were reviewed for clot location and parenchymal abnormalities.

Results: Fifty patients met inclusion criteria, including 12 with CVT. In both groups, children frequently presented with headache and focal neurological deficits. However, the CVT group was more likely to present with seizure (P = 0.0271), altered mental status (P = 0.0271), and a family history of clotting disorder (P = 0.0477). Acute imaging of the CVT group more commonly demonstrated concurrent superior sagittal sinus thrombosis (P = 0.0024) and restricted diffusion (P < 0.0001); and follow-up imaging in the CVT group more commonly showed venous infarction (P = 0.0007).

Conclusions: The presence of CVT in our pediatric CSVT cohort was significantly associated with seizures at presentation, venous-territory restricted diffusion on acute imaging, and venous infarction at follow up. While further work is needed to confirm our results, involvement of cortical veins in CSVT appears to be associated with an increased risk of infarction in children.

Cavernous Sinus Thrombosis in Children

Background and Purpose—

Cavernous sinus thrombosis (CST) is a rare life-threatening cerebrovascular disease known to cause carotid artery narrowing (CAN) and arterial ischemic stroke. The imaging features of CST and related complications have been reported in adults, but rarely in children.

Methods—

We performed a retrospective review of children with imaging confirmed CST from 2003 to 2014, describing presenting symptoms, imaging findings, and treatment.

Results—

Ten patients with CST were identified. All had CAN and 6 of 10 developed infarcts. Of 8 patients treated with anticoagulation therapy, 3 developed new infarcts. None required discontinuation of anticoagulation therapy because of bleeding. Visual impairment secondary to infectious neuritis was common. Imaging characteristics include cavernous sinus expansion, filling defects, restricted diffusion, arterial wall enhancement, empyema, superior ophthalmic vein enlargement and thrombosis, orbital cellulitis, and pituitary inflammation. CAN resolved in 60% of cases. Outcomes were mostly good, with a modified Rankin Scale score of ≤1 for 7 of 10 patients at discharge and 1 death.

Conclusions—

CAN and infarcts were common in this modest cohort of children with CST. Despite the high incidence of CAN and infarction, outcomes were often favorable. Although this is the largest cohort of childhood CST reported to date, large multicenter cohorts are needed to confirm our findings and determine the preferred therapeutic strategies for childhood CST.

Abstract T P364: Carotid Narrowing and Stroke in Childhood Cavernous Sinus Thrombosis

Introduction: Cavernous sinus thrombosis (CST) is a rare and potentially life-threatening disease in children. While the incidence of neurological complication is unknown, CST can cause carotid artery narrowing, carotid vasospasm, and/or ischemia. Given the lack of data regarding childhood CST, decisions about antithrombotic and antispasmodic management remain uncertain.

Hypothesis: We describe the clinical presentation, imaging findings, treatment and outcome of childhood CST at a tertiary care center, hypothesizing that carotid narrowing and stroke are common in this condition.

Methods: We performed a single-center retrospective review of children with imaging confirmed CST from 2003-2013. Clinical data were extracted from the electronic medical record and all available imaging reviewed by two neuroradiologists. Data was analyzed with descriptive statistics.

Results: Eight patients with childhood CST (Table 1) were identified. All had carotid artery narrowing and 63% (5/8) developed ischemia. The most common complication was visual impairment secondary to infectious neuritis. Of the seven patients treated with anticoagulation, three developed new ischemia on therapy. Similar results were seen with nimodipine therapy. Despite the high incidence of stroke, outcomes were generally good, with all but one patient attaining a mRS of ≤ 1at discharge.

Conclusion: In childhood CST, carotid narrowing and arterial ischemic stroke appear to be common. While therapeutic interventions to prevent clot propagation and/or vasospasm did not prevent all new ischemia, they may have contributed to the prevention of medium/large ischemic events, which were uncommon in this series. Despite the high incidence of carotid vasospasm and stroke, outcomes were generally favorable. Large multicenter cohorts are needed to understand the preferred therapeutic strategies for childhood CST.

Abstract T MP62: Acute Infarct Volume in Perinatal Stroke Can Be Accurately Estimated by Measuring Residual Uninfarcted Tissue on Follow-up MRI

Introduction: Developing accurate measurements of infarct volume is vital to studying outcomes in Perinatal Arterial Ischemic Stroke (PAS). Methods for measuring Acute Infarct Volumes (aIV) are well established in PAS. However, techniques for measuring chronic infarct volume (cIV) in order to estimate aIV have not been validated and must account for changes in Total Brain Volume (TBV) over time, as well as contraction of the infarct. We compared two methods of measuring cIV, hypothesizing that cIV extrapolated from residual uninfarcted brain tissue volume would better estimate aIV than direct measurement of cIV.

Methods: Using modified manual segmentation techniques, two pediatric neuroradiologists independently measured the brain and infarct volumes of 10 PAS patients both on the acute (0-7 days old) and chronic (>3 months) MRIs. Volume measurements were averaged after high inter-rater reliability was established (ICC>0.9). We evaluated acute and chronic scans for changes in infarct anatomy, and excluded patients with bilateral infarctions. Method 1 for estimating cIV used a direct measurement of the infarct (figure). Method 2 extrapolated infarct volume from residual uninfarcted brain tissue (figure). The cIV for each method was then compared to the aIV.

Results: 3 patients with bilateral infarcts were excluded. Infarct anatomy between acute and chronic scans did not change for the 7 unilateral infarcts evaluated. In these 7 cases, the ICC comparing aIV and cIV from Method 1 was 0.507 (CI -0.120, 0.891), while the ICC comparing aIV and cIV from Method 2 was 0.964 (CI 0.821, 0.994). cIV’s from Method 1 were smaller than the aIV’s in all cases, despite stability of infarct anatomy.

Conclusions: In this pilot study measuring cIV in PAS, direct measurement of cIV likely underestimates volume because of contraction of infarcted tissue. In conclusion, extrapolation of cIV from measurement of residual uninfarcted tissue appears to accurately estimate aIV.

Moyamoya syndrome associated with Alagille syndrome: outcome after surgical revascularization

Vasculopathy is well-described in Alagille syndrome (ALGS); however, few data exist regarding neurosurgical interventions. We report 5 children with ALGS with moyamoya who underwent revascularization surgery. Postsurgical complications included 1 stroke and 1 death from thalamic hemorrhage. Global function improved in survivors. Revascularization is reasonably safe in patients with ALGS and may improve neurologic outcomes.

Abstract 19: Neurophysiological Responses Of Recovery In Pediatric Mice Compared To Adult Mice With Transient Focal Cerebral Ischemia

Introduction: Ischemic stroke is the fourth leading cause of death in the United States and is increasingly being recognized as a disease that occurs in people of all ages, not just the elderly. Studies suggest that the immature developing brain may have a greater degree of plasticity compared to the adult, thereby enhancing functional recovery to a greater extent during development.

Hypothesis: Pediatric mice exhibit greater recovery from hippocampal synaptic function following experimental stroke than adults.

Methods: Extracellular field recordings of CA1 neurons were performed in acute hippocampal slices prepared at 24 hrs, 7 or 30 days after recovery from middle cerebral artery occlusion (MCAO) and compared to sham control mice.

Results: In adult mice, hippocampal long-term potentiation (LTP) is impaired as early as 24 hrs after experimental stroke and remains impaired for at least 30 days in both the ipsilateral and contralateral, non-injured hemisphere. However, in pediatric mice, LTP is impaired as early as 24 hrs after MCAO and remained impaired in the ipsilateral side 7 days after MCAO, but recovered in the contralateral side at 7 days after MCAO. At day 30 post-stroke, pediatric mice display a full recovery of synaptic function in both hemispheres. Furthermore, significant experimental data is emerging demonstrating an imbalance between inhibitory and excitatory cortical pathways after ischemic stroke, suggesting that reducing GABAergic inhibitory transmission enhances recovery. To test this, hippocampal slices were incubated in L655,708 (100nM), an inverse agonist selective for α5 subunit-containing GABAA receptors. Our data shows that synaptic plasticity was rescued in both pediatric and adult mice in the presence of L655,708 at all-time points tested.

Conclusion: The present study demonstrates that transient focal ischemia causes functional impairment in the hippocampus at various time points after MCAO and that recovery of synaptic function is more robust in the young brain. In addition, we observed that excessive GABA activity may contribute to impaired synaptic function following ischemic injury, thus inhibition of specific GABA activity may provide a new therapeutic approach to improve functional recovery after stroke.

Out-of-pocket costs for childhood stroke: the impact of chronic illness on parents' pocketbooks

OBJECTIVE

Direct costs for children who had stroke are similar to those for adults. There is no information regarding the out-of-pocket costs families encounter. We described the out-of-pocket costs families encountered in the first year after a child's ischemic stroke.

METHODS

Twenty-two subjects were prospectively recruited at four centers in the United States and Canada in 2008 and 2009 as part of the "Validation of the Pediatric NIH Stroke Scale" study; families' indirect costs were tracked for 1 year. Every 3 months, parents reported hours they did not work, nonreimbursed costs for medical visits or other health care, and mileage. They provided estimates of annual income. We calculated total out-of-pocket costs in US dollars and reported costs as a proportion of annual income.

RESULTS

Total median out-of-pocket cost for the year after an ischemic stroke was $4354 (range, $0-$28,666; interquartile range, $1008-$8245). Out-of-pocket costs were greatest in the first 3 months after the incident stroke, with the largest proportion because of lost wages, followed by transportation, and nonreimbursed health care. For the entire year, median costs represented 6.8% (range, 0%-81.9%; interquartile range, 2.7%-17.2%) of annual income.

CONCLUSIONS

Out-of-pocket expenses are significant after a child's ischemic stroke. The median costs are noteworthy provided that the median American household had cash savings of $3650 at the time of the study. These results with previous reports of direct costs provide a more complete view of the overall costs to families and society. Childhood stroke creates an under-recognized cost to society because of decreased parental productivity.

Arteriopathy diagnosis in childhood arterial ischemic stroke: results of the vascular effects of infection in pediatric stroke study

BACKGROUND AND PURPOSE

Although arteriopathies are the most common cause of childhood arterial ischemic stroke, and the strongest predictor of recurrent stroke, they are difficult to diagnose. We studied the role of clinical data and follow-up imaging in diagnosing cerebral and cervical arteriopathy in children with arterial ischemic stroke.

METHODS

Vascular effects of infection in pediatric stroke, an international prospective study, enrolled 355 cases of arterial ischemic stroke (age, 29 days to 18 years) at 39 centers. A neuroradiologist and stroke neurologist independently reviewed vascular imaging of the brain (mandatory for inclusion) and neck to establish a diagnosis of arteriopathy (definite, possible, or absent) in 3 steps: (1) baseline imaging alone; (2) plus clinical data; (3) plus follow-up imaging. A 4-person committee, including a second neuroradiologist and stroke neurologist, adjudicated disagreements. Using the final diagnosis as the gold standard, we calculated the sensitivity and specificity of each step.

RESULTS

Cases were aged median 7.6 years (interquartile range, 2.8-14 years); 56% boys. The majority (52%) was previously healthy; 41% had follow-up vascular imaging. Only 56 (16%) required adjudication. The gold standard diagnosis was definite arteriopathy in 127 (36%), possible in 34 (9.6%), and absent in 194 (55%). Sensitivity was 79% at step 1, 90% at step 2, and 94% at step 3; specificity was high throughout (99%, 100%, and 100%), as was agreement between reviewers (κ=0.77, 0.81, and 0.78).

CONCLUSIONS

Clinical data and follow-up imaging help, yet uncertainty in the diagnosis of childhood arteriopathy remains. This presents a challenge to better understanding the mechanisms underlying these arteriopathies and designing strategies for prevention of childhood arterial ischemic stroke.

Etiology and treatment of arterial ischemic stroke in children and young adults

OPINION STATEMENT

Stroke is the second leading cause of death worldwide (Go et al. Circulation 129:e28-292, 2014) and is a major cause of morbidity and mortality. Compared with older adults, arterial ischemic stroke (AIS) is relatively uncommon in children and young adults, comprising 5-10 % of all stroke (Biller Nat Rev Cardiol 6:395-97, 2009), but is associated with significant cost. In contrast to the declining overall incidence of stroke, some early studies suggest that the rate of stroke hospitalizations in children and young adults is rising (George et al. Ann Neurol 70:713-21, 2011; Kissela et al. Stroke 41:e224, 2010; Nguyen-Huynh et al. Stroke 43, 2012), emphasizing the importance of understanding the similarities and differences in etiology and treatment of AIS across the age spectrum. Among the most common causes of AIS in children are cardioembolism (often related to congenital heart disease), cervicocephalic arterial dissections, focal arteriopathy of childhood and several genetic and metabolic disorders, such as sickle cell disease (SCD). AIS in young adults is less well understood, but likely overlaps in etiology with both children and older adults. Young adults with AIS often have classic atherosclerotic risk factors similar to older adults, but are also more likely to have thrombophilias, cervicocephalic arterial dissections and cardioembolism, similar to children with AIS. Since little evidence exists regarding both acute treatment and secondary prevention after AIS in children and young adults, standard treatment practices are mainly extrapolated from research done in older adults. In most cases we recommend treating young adults per the guidelines published by the American Heart Association for adults with stroke (Jauch et al. Stroke 44:870-947, 2013; Kernan et al. Stroke 45:2160-2236, 2014) and children per the equivalent guidelines regarding pediatric stroke (Roach et al. Stroke 39:2644-91, 2008). It is also important in children and young adults to consider less common structural, metabolic and genetic risk factors for stroke, which may require more specific treatment. Other standard risk factors for stroke, including hypertension, hyperlipidemia and diabetes mellitus should also be addressed, but are less likely in children and young adults. Given the lack of data and possibility of rare underlying etiologies such as Antiphospholipid Antibody Syndrome or Ehlers-Danlos syndrome, we recommend including multiple specialists in the care of these patients, such as hematologists and vascular neurologists.

Emergence of the primary pediatric stroke center: impact of the thrombolysis in pediatric stroke trial

BACKGROUND AND PURPOSE

In adult stroke, the advent of thrombolytic therapy led to the development of primary stroke centers capable to diagnose and treat patients with acute stroke rapidly. We describe the development of primary pediatric stroke centers through preparation of participating centers in the Thrombolysis in Pediatric Stroke (TIPS) trial.

METHODS

We collected data from the 17 enrolling TIPS centers regarding the process of becoming an acute pediatric stroke center with capability to diagnose, evaluate, and treat pediatric stroke rapidly, including use of thrombolytic therapy.

RESULTS

Before 2004, <25% of TIPS sites had continuous 24-hour availability of acute stroke teams, MRI capability, or stroke order sets, despite significant pediatric stroke expertise. After TIPS preparation, >80% of sites now have these systems in place, and all sites reported increased readiness to treat a child with acute stroke. Use of a 1- to 10-Likert scale on which 10 represented complete readiness, median center readiness increased from 6.2 before site preparation to 8.7 at the time of site activation (P≤0.001).

CONCLUSIONS

Before preparing for TIPS, centers interested in pediatric stroke had not developed systematic strategies to diagnose and treat acute pediatric stroke. TIPS trial preparation has resulted in establishment of pediatric acute stroke centers with clinical and system preparedness for evaluation and care of children with acute stroke, including use of a standardized protocol for evaluation and treatment of acute arterial stroke in children that includes use of intravenous tissue-type plasminogen activator.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT01591096.

Abstract 42: Chronic Endothelial Activation in Childhood Arterial Ischemic Stroke

Objective: Despite evidence suggesting that arterial inflammation plays a role in the pathophysiology of childhood arterial ischemic stroke (AIS), relatively little is known about inflammatory induced coagulation and/or endothelial activation. The object of this study was to compare biomarkers of coagulation activation [D-dimer and thrombin-antithrombin complex (TAT)] and endothelial activation [Plasminogen activator inhibitor-1 (PAI-1) and von Willebrand factor antigen (vWF Ag)] in children with AIS as compared to healthy pediatric controls.

Methods: Sixty patients with childhood AIS (ages 28 days to 19 years) were enrolled in a prospective six-center study. Biomarker samples were collected in the acute (0-3 weeks post-AIS) and chronic (> 3 months post-AIS) timeframes. Healthy pediatric controls were enrolled at the central site. Biomarker differences by group were examined using t-test, chi-square, and, if demographics differed, regression models.

Results: Age and gender were similar in all case and control groups, except age in acute vWF Ag and D-dimer populations [mean (SD): vWF Ag age = 9.3 yrs. (5.2), control age = 6.9 yrs. (4.3), P=0.007 ; D-Dimer age = 9.4 yrs. (5.2), control age = 7.3 yrs. (4.3), P=0.032 ]. All acute biomarkers were significantly elevated in cases as compared to healthy controls, while only markers of endothelial activation remained significantly elevated in cases during the chronic phase (PAI-1 P=0.0014 ; vWF Ag P=0.0002 ; Table).

Conclusion: Children with AIS have increased levels of endothelial and coagulation activation during the acute phase following stroke, while endothelial biomarkers remain elevated beyond 3 months. These results suggest that endothelial activation persists into the chronic phase of childhood AIS. Future studies with larger cohorts and stroke subtype analysis are needed to evaluate the use of endothelial biomarkers as surrogates of ongoing disease and recurrence risk.

The methylenetetrahydrofolate reductase polymorphism (MTHFR c.677C>T) and elevated plasma homocysteine levels in a U.S. pediatric population with incident thromboembolism

OBJECTIVE

Elevated plasma homocysteine (tHcy) and the MTHFR c.677C>T variant have been postulated to increase the risk of venous thromboembolism (VTE), although mechanisms and implications to pediatrics remain incompletely understood. The objectives of this study were to determine the prevalences of elevated tHcy and MTHFR variant in a pediatric population with VTE or arterial ischemic stroke (AIS), and to determine associations with thrombus outcomes.

STUDY DESIGN

Subjects were enrolled in an institution-based prospective cohort of children with VTE or AIS. Inclusion criteria consisted of objectively confirmed thrombus, ≤21years at diagnosis, tHcy measured and MTHFR c.677C>T mutation analysis. Clinical and laboratory data were collected. Frequencies for elevated tHcy and MTHFR variant were compared with NHANES values for healthy US children and also between study groups (VTE vs AIS, provoked vs idiopathic) and by age.

RESULTS

The prevalences of hyperhomocysteinemia or MTHFR variant were not increased in comparison to NHANES. tHcy did not differ between those with wild-type MTHFR versus either c.677C>T heterozygotes or homozygotes. There was no association between tHcy or MTHFR variant and thrombus outcomes.

CONCLUSION

In this cohort of US children with VTE or AIS, neither the prevalence of hyperhomocysteinemia nor that of MTHFR variant was increased relative to reference values, and adverse thrombus outcomes were not definitively associated with either. While it is important to consider that milder forms of pyridoxine-responsive classical homocystinuria will be detected only by tHcy, we suggest that routine testing of MTHFR c.677C>T genotype as part of a thrombophilia evaluation in children with incident thromboembolism is not warranted until larger studies have been performed in order to establish or refute a link between MTHFR and adverse outcomes.

Arteriopathy, D-dimer, and risk of poor neurologic outcome in childhood-onset arterial ischemic stroke

OBJECTIVE

To assess whether acute findings of cerebral arteriopathy, large infarct, and acutely elevated plasma D-dimer levels are independently prognostic of poor long-term neurologic outcome as measured at ≥ 1 year post-event in children with arterial ischemic stroke (AIS).

STUDY DESIGN

Sixty-one patients with childhood-onset (ie, >28 days of life) AIS were enrolled in a single-institution cohort study at Children's Hospital Colorado between February 2006 and June 2011. Data on demographic and diagnostic characteristics, antithrombotic treatments, and outcomes were systematically collected.

RESULTS

Cerebral arteriopathy and D-dimer levels >500 ng/mL (a measure of coagulation activation) were identified acutely in 41% and 31% of the cohort, respectively. Anticoagulation was administered in the acute period post-event in 40% of the children, in the subacute period in 43%, and in the chronic period in 28%. When not receiving anticoagulation, patients were routinely treated with aspirin 2-5 mg/kg once daily for a minimum of 1 year. Death, major bleeding (including intracranial hemorrhage), and recurrent AIS were infrequent. The Pediatric Stroke Outcome Measure at 1 year demonstrated poor outcome in 54% of the children. Acute cerebral arteriopathy and elevated D-dimer level were identified as putative prognostic factors for poor outcome; after adjustment for D-dimer, arteriopathy was an independent prognostic indicator (OR, 19.0; 95% CI, 1.6-229.8; P = .02).

CONCLUSION

Arteriopathy and coagulation activation are highly prevalent in the acute period of childhood AIS. Although recurrent AIS and intracranial hemorrhage were infrequent in our cohort, one-half of children experienced a poor neurologic outcome at 1 year, the risk of which was increased by acute arteriopathy. Substantiation of these findings in multi-institutional cohort studies is warranted, toward risk stratification in childhood-onset AIS.

Overweight and obesity are increased in childhood-onset cerebrovascular disease

The objective of this work was to determine whether overweight/obesity is a risk factor for cerebrovascular disease in children. The study included 53 children with non-neonatal-onset cerebral sinovenous thrombosis or arterial ischemic stroke. The prevalence of overweight/obesity was compared between this cohort and healthy children from the National Health and Nutrition Examination Survey. In addition, cerebral sinovenous thrombosis patients were compared to a group of matched hospitalized controls. The prevalence of overweight/obesity was significantly higher in the cerebral sinovenous thrombosis cohort (55%), but not the arterial ischemic stroke cohort (36%), relative to national controls (32%; P = .04 and P = .81, respectively). Similarly, the prevalence of overweight/obesity was significantly higher in the cerebral sinovenous thrombosis cohort than in Colorado controls (25%; P = .02). In conclusion, the prevalence of overweight/obese was significantly increased in cerebral sinovenous thrombosis patients as compared to both national and local controls. Results should be evaluated in a larger multi-institutional cohort.