Neuropsychological Outcome in Perinatal Stroke Associated With Epileptiform Discharges in Sleep

Incidence and risk factors of post-stroke seizures and epilepsy: systematic review and meta-analysis

OBJECTIVE

Due to variability in reports, the aim of this meta-analysis was to evaluate the incidence and risk factors of post-stroke early seizures (ES) and post-stroke epilepsy (PSE).

METHODS

The MEDLINE, EMBASE and Web of Science databases were searched for post-stroke ES/PSE articles published on any date up to November 2020. Post-stroke ES included seizures occurring within 7 days of stroke, and PSE included at least one unprovoked seizure. Using random effects models, the incidence and risk factors of post-stroke ES and PSE were evaluated. The study was retrospectively registered with INPLASY (INPLASY2023100008).

RESULTS

Of 128 included studies in total, the incidence of post-stroke ES was 0.07 (95% confidence interval [CI] 0.05, 0.10) and PSE was 0.10 (95% CI 0.08, 0.13). The rates were higher in children than adults. Risk factors for post-stroke ES included hemorrhagic stroke (odds ratio [OR] 2.14, 95% CI 1.44, 3.18), severe strokes (OR 2.68, 95% CI 1.73, 4.14), cortical involvement (OR 3.09, 95% CI 2.11, 4.51) and hemorrhagic transformation (OR 2.70, 95% CI 1.58, 4.60). Risk factors for PSE included severe strokes (OR 4.92, 95% CI 3.43, 7.06), cortical involvement (OR 3.20, 95% CI 2.13, 4.81), anterior circulation infarcts (OR 3.28, 95% CI 1.34, 8.03), hemorrhagic transformation (OR 2.81, 95% CI 1.25, 6.30) and post-stroke ES (OR 7.24, 95% CI 3.73, 14.06).

CONCLUSION

Understanding the risk factors of post-stroke ES/PSE may identify high-risk individuals who might benefit from prophylactic treatment.

The thalamus and basal ganglia are smaller in children with epilepsy after perinatal stroke

Background

Epilepsy is one of the most serious consequences of perinatal stroke. Epilepsy itself has been proposed as a risk factor for impaired cognitive, language, and behavioral functioning. It is still unclear which children develop epilepsy after perinatal stroke. The current study aimed to evaluate the volume of the thalamus and the basal ganglia in children after perinatal stroke in relation to poststroke epilepsy.

Methods

The follow-up study included 29 children with perinatal arterial ischemic stroke (AIS), 33 children with presumed periventricular venous infarction (PVI), and 46 age- and sex-matched healthy controls. Magnetic resonance imaging was performed in children between the ages of 4 and 18 years, and volumetric analysis by segmentation was used to evaluate the size of the thalamus, caudate nucleus, putamen, globus pallidus, hippocampus, amygdala, and nucleus accumbens.

Results

During a median follow-up time of 12.8 years [interquartile range (IQR): 10.8-17.3] in the AIS group and 12.5 years (IQR: 9.3-14.8) in the PVI group (p = 0.32), epilepsy developed in 10 children (34.5%) with AIS and in 4 (12.1%) children with PVI, p = 0.036 [odds ratio (OR) = 3.8, 95%, confidence interval (CI): 1.04-14]. Epilepsy and interictal epileptiform discharges (IEDs) without clinical seizures were more often expressed in children with AIS (n = 16, 55%) than in children with PVI (n = 7, 21.2%), p = 0.0057 (OR = 3.8 95% CI: 1.04-14). In the AIS group, the ipsilesional and contralesional thalamus, ipsilesional caudate nucleus, and nucleus accumbens were significantly smaller in children with epilepsy compared to children without epilepsy. In the PVI group, the ipsilesional thalamus, caudate nucleus, and nucleus accumbens were smaller in the pooled group of epilepsy plus IED alone compared to children without epilepsy.

Conclusion

In children with AIS, epilepsy or IED occurred more often compared to children with PVI. Both patients with AIS and PVI with severe damage to the basal ganglia and the thalamus have a higher risk of developing poststroke epilepsy and should be monitored more closely throughout childhood to initiate timely antiseizure medication and rehabilitation.

Learning and memory profiles in youth with perinatal stroke: a study of the Child and Adolescent Memory Profile (ChAMP)

There is limited understanding of the effect of perinatal stroke on child and adolescent learning and memory abilities. This study sought to evaluate the clinical utility of the Child and Adolescent Memory Profile (ChAMP) in quantifying memory performance in youth with perinatal stroke. Children and adolescents aged 6-16 years old with a history of perinatal stroke (PS; n = 41) completed two subtests from the ChAMP (Lists and Objects). Age, sex, and ethnicity-matched healthy control (HC) data were obtained from the test publisher's standardization data set. Participants with a history of PS performed significantly worse (p < .05) with medium effect size (ƞ_p² ≥ .06) than HC on the ChAMP Screening Index and on all ChAMP Lists and Objects scaled scores. Classification accuracy for the ChAMP scores ranged from 57% to 68% with the area under the curve ranging from .62-.75. No significant group differences on ChAMP performance (p > .05) were found for stroke side (left versus right-sided) or for seizure history (present versus absent). This study supports the utility of the ChAMP in perinatal stroke patients by demonstrating significantly worse performance in verbal and visual memory than HC. Classification accuracy is limited, but supportive for the Screening Index and Objects Delayed scores. The ChAMP may be a useful tool for evaluating cognition in this population when taken alongside the context of other tests, background history, and clinical observations.

Perinatal stroke: mapping and modulating developmental plasticity

Most cases of hemiparetic cerebral palsy are caused by perinatal stroke, resulting in lifelong disability for millions of people. However, our understanding of how the motor system develops following such early unilateral brain injury is increasing. Tools such as neuroimaging and brain stimulation are generating informed maps of the unique motor networks that emerge following perinatal stroke. As a focal injury of defined timing in an otherwise healthy brain, perinatal stroke represents an ideal human model of developmental plasticity. Here, we provide an introduction to perinatal stroke epidemiology and outcomes, before reviewing models of developmental plasticity after perinatal stroke. We then examine existing therapeutic approaches, including constraint, bimanual and other occupational therapies, and their potential synergy with non-invasive neurostimulation. We end by discussing the promise of exciting new therapies, including novel neurostimulation, brain-computer interfaces and robotics, all focused on improving outcomes after perinatal stroke.

Automated quantification of spike-wave activity may be used to predict the development of electrical status epilepticus in sleep (ESES) in children with perinatal stroke

OBJECTIVE

Continuous spike and wave in slow-wave sleep (CSWS), an epileptic encephalopathy, occurs after perinatal stroke where it is associated with cognitive decline. CSWS features a distinct EEG pattern, electrical status epilepticus in sleep (ESES). Biomarkers for the prediction of ESES have not been identified but will facilitate earlier diagnosis and treatment. We hypothesized that spike-frequency and differences in power spectra would be predictive of subsequent ESES.

METHODS

A cross-sectional study comparing EEG spike-frequency and Power before the development of ESES in patients with perinatal stroke, patients with focal epilepsy, and appropriate controls.

RESULTS

43 patients met the inclusion criteria; 11 stroke-ESES, 10 stroke controls, 14 epilepsy-ESES, 8 epilepsy controls. ESES patients had higher pre-diagnosis mean spike-frequency (24.0 ± 24 versus 6.6 ± 9.1 SW/min, p = 0.002) than patients that did not develop ESES; these differences present ~ 3 years before ESES diagnosis. Pre-diagnosis, normalized delta power (1-4 Hz) was higher in the stroke-ESES group (105.7 ± 58 dB/Hz) compared to stroke controls (57.4 ± 45 dB/Hz, p = 0.036).

CONCLUSION

Spike-frequency and delta power may represent EEG biomarkers of the risk of developing ESES in children with perinatal stroke.

SIGNIFICANCE

EEG biomarkers may be used by clinicians to assess which patients are more at-risk for ESES. Using spike-frequency, clinicians may be able to identify patients at risk of developing ESES.

Electrical status epilepticus in sleep (ESES) - Treatment pattern and EEG outcome in children with very high spike-wave index

OBJECTIVE

The objective of the study was to determine electrical status epilepticus in sleep (ESES) outcome in children with very high spike-wave index (SWI; ≥85%), and assess treatment pattern.

METHODS

Medical records of children 1-17 years old with ESES were reviewed. In this study, ESES is defined as SWI in non-rapid eye movement (non-REM) sleep of ≥85%. Electrical status epilepticus in sleep resolution is defined as reduction of SWI to <50%.

RESULTS

Complete data were available in 33 children. Age at ESES diagnosis ranged from 32 to 165 months, median 76 months. The median duration of follow-up was 33 months. Two-thirds of the children were on one or more antiepileptic drugs (AED) at ESES diagnosis. Antiepileptic drugs were used as first treatment for ESES in 24/33 (73%). Electrical status epilepticus in sleep initially resolved in 76%, but 56% had subsequent relapse. The relapse rate was higher for steroids (89%) and benzodiazepines (60%) as compared with nonbenzodiazepine AEDs (29%). At last follow-up, ESES resolved in 21 children (64%). Electrical status epilepticus in sleep resolution was associated with seizure freedom (Fisher's exact, p < 0.05).

SIGNIFICANCE

Using electroencephalogram (EEG) criteria, ESES resolved in 64%. We found high failure rate of first-line AEDs in preventing ESES, and high relapse rate. Standardization of ESES management is urgently needed.

Long-Term Outcome After Bilateral Perinatal Arterial Ischemic Stroke

AIM

We aimed to characterize the phenotype and outcome of children with bilateral, large vessel perinatal arterial ischemic stroke.

METHODS

Patients with bilateral, large vessel perinatal arterial ischemic stroke were identified from a large, population-based cohort (Alberta Perinatal Stroke Project). Subjects were included if stroke involving a major cerebral artery territory was documented in both cerebral hemispheres on magnetic resonance imaging. Standardized variables were extracted from charts including clinical presentations, associated potential risk factors, and outcomes. Outcome measures included the Pediatric Stroke Outcome Measure, Gross Motor Function Classification System, and epilepsy frequency score. Electroencephalographies were reviewed for sleep, epileptiform activity, and background.

RESULTS

Of 174 children with perinatal arterial ischemic stroke, eight (5%) had bilateral large artery infarcts. Patients were followed for a mean of 9.7 years (range 1.8 to 14.6 years). One child died. All children had a total Pediatric Stroke Outcome Measure of ≥2 (median 8, range 2 to 10) and Gross Motor Function Classification System ≥ II. Seven of eight (88%) children had a history of epilepsy.

CONCLUSIONS

Children with bilateral, large vessel perinatal stroke are at high risk of severe cognitive and motor sequelae. Epilepsy may also be more common than unilateral strokes. Cautious discussions with families regarding prognosis are recommended.

Perinatal stroke: mechanisms, management, and outcomes of early cerebrovascular brain injury

Perinatal stroke encompasses a heterogeneous group of focal neurological injuries early in brain development that probably affects more than 5 million people worldwide. Many such injuries are symptomatic in the first days of life, including neonatal arterial ischaemic stroke, cerebral sinovenous thrombosis, and neonatal haemorrhagic stroke. The remaining focal neurological injuries usually present later in the first year with motor asymmetry, such as arterial presumed perinatal ischaemic stroke, periventricular venous infarction, and presumed perinatal haemorrhagic stroke. The numerous sequelae of these injuries include hemiparesis (cerebral palsy), epilepsy, and cognitive, language, and behavioural challenges. In this Review we summarise each perinatal stroke disease, examining the epidemiology, pathophysiology, acute management, and outcomes, including the effect on parents and families, and emerging therapies to mitigate these lifelong morbidities.

Bihemispheric alterations in myelination in children following unilateral perinatal stroke

Background

Stroke is a leading cause of perinatal brain injury with variable outcomes including cerebral palsy and epilepsy. The biological processes that underlie these heterogeneous outcomes are poorly understood. Alterations in developmental myelination are recognized as a major determinant of outcome in preterm brain injury but have not been explored in perinatal stroke. We aimed to characterize myelination in hemiparetic children after arterial perinatal stroke, hypothesizing that ipsilesional myelination would be impaired, the degree of which would correlate with poor outcome.

Methods

Retrospective, controlled cohort study. Participants were identified through the Alberta Perinatal Stroke Project (APSP), a population-based research cohort (n > 400). Inclusion criteria were: 1) MRI-confirmed, unilateral arterial perinatal stroke, 2) T1-weighted MRI after 6 months of age, 3) absence of other neurological disorders, 4) neurological outcome that included at least one of the following tests - Pediatric Stroke Outcome Measure (PSOM), Assisting Hand Assessment (AHA), Melbourne Assessment (MA), neuropsychological evaluation (NPE), and robotic sensorimotor measurements. FreeSurfer software measured hemispheric asymmetry in myelination intensity (primary outcome). A second method using ImageJ software validated the detection of myelination asymmetry. A repeated measures ANOVA was used to compare perilesional, ipsilesional remote, and contralesional homologous region myelination between stroke cases and typically developing controls. Myelination metrics were compared to clinical outcome measures (t-test, Pearson's correlation).

Results

Twenty youth with arterial stroke (mean age: 13.4 ± 4.2yo) and 27 typically developing controls (mean age: 12.5 ± 3.7yo) were studied in FreeSurfer. Participants with stroke demonstrated lower myelination in the ipsilesional hemisphere (p < 0.0001). Myelination in perilesional regions had lower intensity compared to ipsilesional remote areas (p < .00001) and contralesional homologous areas (p < 0.00001). Ipsilesional remote regions had decreased myelination compared to homologous regions on the contralesional hemisphere (p = 0.016). Contralesional myelination was decreased compared to controls (p < 0.00001). Myelination metrics were not strongly associated with clinical motor, robotic sensorimotor, or neuropsychological outcomes though some complex tests requiring speeded responses had moderate effect sizes.

Conclusion

Myelination of apparently uninjured brain in both the ipsilesional and contralesional hemispheres is decreased after perinatal stroke. Differences appear to radiate outward from the lesion. Further study is needed to determine clinical significance.

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Myelination is altered in the lesioned hemisphere after perinatal stroke.

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The uninjured, contralesional hemisphere also demonstrates differences in myelination.

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Simple software can estimate MRI myelination abnormalities in children with perinatal brain injury.