MRI findings in infants with infantile spasms after neonatal hypoxic-ischemic encephalopathy

MRI predictors of long-term outcomes of neonatal hypoxic ischaemic encephalopathy: a primer for radiologists

This review aims to serve as a foundational resource for general radiologists, enhancing their understanding of the role of Magnetic Resonance Imaging (MRI) in early prognostication for newborns diagnosed with hypoxic ischaemic encephalopathy (HIE). The article explores the application of MRI as a predictive instrument for determining long-term outcomes in newborns affected by HIE. With HIE constituting a leading cause of neonatal mortality and severe long-term neurodevelopmental impairments, early identification of prognostic indicators is crucial for timely intervention and optimal clinical management. We examine current literature and recent advancements to provide an in-depth overview of MRI predictors, encompassing brain injury patterns, injury scoring systems, spectroscopy, and diffusion imaging. The potential of these MRI biomarkers in predicting long-term neurodevelopmental outcomes and the probability of epilepsy is also discussed.

Neonatal brain MRI and short-term outcomes after acute provoked seizures

OBJECTIVE

We investigated how diagnosis and injury location on neonatal brain MRI following onset of acute provoked seizures was associated with short term outcome.

STUDY DESIGN

A multicenter cohort of neonates with acute provoked seizures enrolled in the Neonatal Seizure Registry. MRIs were centrally evaluated by a neuroradiologist for location of injury and radiologic diagnosis. Clinical outcomes were determined by chart review. Multivariate logistic regression was used to examine the association between MRI findings and outcomes.

RESULTS

Among 236 newborns with MRI at median age 4 days (IQR 3-8), 91% had abnormal MRI. Radiologic diagnoses of intracranial hemorrhage (OR 3.2 [1.6-6.5], p < 0.001) and hypoxic-ischemic encephalopathy (OR 2.7 [1.4-5.4], p < 0.003) were associated with high seizure burden. Radiologic signs of intracranial infection were associated with abnormal neurologic examination at discharge (OR 3.9 [1.3-11.6], p < 0.01).

CONCLUSION

Findings on initial MRI can help with expectant counseling on short-term outcomes following acute provoked neonatal seizures.

Brain Magnetic Resonance Imaging Findings in Infantile Spasms

Background: Infantile spasms are an age-specific epileptic disorder. They occur in infancy and early childhood. They can be caused by multiple etiologies. Structural abnormalities represent an important cause of infantile spasms. Brain magnetic resonance imaging (MRI) is one of the integral modalities in the evaluation of this condition. Purpose: The aim of this study is to review and analyze the clinical characteristics and brain MRI findings in a cohort of children diagnosed with infantile spasms. Material and Methods: A cohort of fifty-six children diagnosed with infantile spasms in infancy and early childhood was included. All of them underwent brain MRI for evaluation. The study was conducted in the period from January 2016 to January 2020. Results: Females comprised 57% of the cohort. The mean age for seizure onset was 5.9 months (SD 2.7). Forty-one patients (73%) had active epilepsy, and 51% were diagnosed with global developmental delay. Consanguinity was present in 59% of the cohort. Most of the follow-up MRIs showed structural abnormalities (84%). Hypoxia was reported in 17% of MRIs. Malformations of cortical development were seen in five patients. Brain MRI findings were normal in 16% of patients, and delayed myelination was seen in nineteen patients. Most of the children with active epilepsy (64%) and developmental delay (82%) had an abnormal brain MRI. It was noticed that abnormal second brain MRIs were more likely to be associated with active epilepsy and developmental delay (p = 0.05). Conclusions: Brain MRI is an integral part of infantile spasms’ clinical evaluation. Infantile spasms and abnormal brain MRI can be associated with active epilepsy and global developmental delay.

Management of seizures in neonates with neonatal encephalopathy treated with hypothermia

Neonatal encephalopathy (NE) is the most common etiology of acute neonatal seizures - about half of neonates treated with therapeutic hypothermia for NE have EEG-confirmed seizures. These seizures are best identified with continuous EEG monitoring, as clinical diagnosis leads to under-diagnosis of subclinical seizures and over-treatment of events that are not seizures. High seizure burden, especially status epilepticus, is thought to augment brain injury. Treatment, therefore, is aimed at minimizing seizure burden. Phenobarbital remains the mainstay of treatment, as it is more effective than levetiracetam and easier to administer than fosphenytoin. Emerging evidence suggests that, for many neonates, it is safe to discontinue the phenobarbital after acute seizures resolve and prior to hospital discharge.

Patterns of Brain Injury in Perinatal Arterial Ischemic Stroke and the Development of Infantile Spasms

INTRODUCTION

Perinatal arterial ischemic stroke (PAIS) underlies approximately 10% of infantile spasms (IS). We aim to identify patterns of brain injury in ischemic stroke that may predispose infants to infantile spasms.

METHODS

Sixty-four perinatal arterial ischemic stroke patients were identified meeting the following inclusion criteria: term birth, magnetic resonance imaging (MRI) showing ischemic stroke or encephalomalacia in an arterial distribution, and follow-up records. Patients who developed infantile spasms (PAIS-IS) were analyzed descriptively for ischemic stroke injury patterns and were compared to a seizure-free control group (PAIS-only). Stroke injury was scored using the modified pediatric ASPECTS (modASPECTS).

RESULTS

The PAIS-IS (n = 9) group had significantly higher modASPECTS than the PAIS-only (n = 16) group (P = .002, Mann-Whitney). A greater proportion of PAIS-IS patients had injury to deep cerebral structures (67%) than PAIS-only (25%).

CONCLUSION

Infarct size was significantly associated with infantile spasms development. Results support theories implicating deep cerebral structures in infantile spasms pathogenesis. This may help identify perinatal arterial ischemic stroke patients at risk of infantile spasms, facilitating more timely diagnosis.

Clinical seizures and unfavorable brain MRI patterns in neonates with hypoxic ischemic encephalopathy

The aim was to examine whether clinical seizures and amplitude-integrated electroencephalogram (aEEG) patterns in infants with hypoxic ischemic encephalopathy (HIE) can predict the extent of brain injury on magnetic resonance images (MRI) and the long-term neurodevelopmental outcomes at 18∼24 months of age.HIE infants who underwent therapeutic hypothermia (TH) between June 2014 and March 2017 were included in this study. Infants with clinical seizure were analyzed for aEEG patterns and the extent of brain injury on MRI findings. Clinical seizure, aEEG, and brain MRI were assessed and compared with neurodevelopmental outcomes at 18∼24 months of age.Among the 97 HIE infants enrolled in this study with brain MRI scans, 78 (73.1%) TH-treated HIE infants exhibited clinical seizures. More abnormalities on a EEGs and more significant use of first and second antiepileptic drugs (AEDs) were significantly higher in the clinical-seizure group with longer hospitalized days. At a corrected 18 to 24 months of age, HIE infants in the clinical-seizure group with more extension of injury lesions on diffusion-weighted MRI scans exhibited significantly more delayed neurodevelopment. A risk factor analysis indicated that male infants who stayed in the hospital for more than 11 days were at a higher risk of having clinical seizures. The lesion size in MRI greater than 37 pixels was a risk factor with an 81.8% accuracy.Seizures in HIE infants may predict abnormal brain MRI scans and abnormal neurodevelopment at 18 to 24 months of age.

MiR-127-3p targeting CISD1 regulates autophagy in hypoxic-ischemic cortex

Neonatal hypoxic-ischemic (HI) injury derived from asphyxia during perinatal period, is a serious complication of neonatal asphyxia and the main cause of neonatal acute death and chronic neurological injury. Aberrant autophagy occurs in many nervous system diseases, but its role and underlying mechanism in HI injury is largely unknown. Here, we successfully constructed a newborn rat model of HI brain injury, and the knockout-miR-127-3p (KO-miR-127-3p) rats were structured by using CRISPR/Cas9. Subsequently, the in vitro functional experiments, in vivo zea-longa scores, as well as bioinformatics analyses and biological experiments were applied. The expression of autophagy-related proteins, including ATG12, P62, Beclin-1, LC3II in HI cortex with miR-127-3p knockout was significantly decreased, and autophagic vacuoles were disappeared. Moreover, miR-127-3p has a specific regulatory effect on CISD1 expression, another crucial molecule in autophagy process. Accordingly, the overexpression of CISD1 effectively inhibited the autophagic cell death and physiological dysfunction in the brain of HI injury, whereas si-CISD1 reversed the neuroprotective effects of KO-miR-127-3p. Our findings explained the underlying mechanism for HI injury, and miR-127-3p targeting CISD1 signal could be supposed as a new treatment strategy to prevent and treat HI injury.

The prognosis of brain magnetic resonance imaging injury pattern for outcomes of hypothermia-treated infants

Magnetic resonance imaging (MRI) can be a tool that allows the observation of structural injury patterns after cooling. The aim of this study was to determine the early pattern of brain injury in the MRIs of infants with hypoxic ischemic encephalopathy (HIE) after cooling and to search for any clinical factors related to abnormal MRI findings.The study retrospectively recruited 118 infants who were treated with therapeutic hypothermia (TH) between 2013 and 2016.Forty-three patients had normal brain MRI, and 75 had abnormal brain MRI findings. The TH-treated infants with abnormal brain MRI readings showed significantly more clinical seizures and the use of additional antiepileptic drugs (AEDs) than the normal MRI group. As a long-term outcome, more lesions in the basal ganglia and thalamus, posterior limb of internal capsule, or severe white matter lesions were associated with abnormal neurodevelopmental outcomes at 18 to 24 months of age.A higher frequency of clinical seizures and AED use were related to abnormal brain injury on MRI. A significant risk for poor long-term outcomes was found in the abnormal brain MRI group.

Risk for infantile spasms after acute symptomatic neonatal seizures

OBJECTIVE

Infantile spasms (IS) is a severe epilepsy in early childhood. Early treatment of IS provides the best chance of seizure remission and favorable developmental outcome. We aimed to develop a prediction rule to accurately predict which neonates with acute symptomatic seizures will develop IS.

METHODS

We used data from the Neonatal Seizure Registry, a prospective, multicenter cohort of infants with acute symptomatic neonatal seizures born from July 2015 to March 2018. Neonates with acute symptomatic seizures who received clinical electroencephalography (EEG) and magnetic resonance imaging (MRI) and were younger than 2 years of age at the time of enrollment were included. We evaluated the association of neonatal EEG, MRI, and clinical factors with subsequent IS using bivariate analysis and best subsets logistic regression. We selected a final model through a consensus process that balanced statistical significance with clinical relevance.

RESULTS

IS developed in 12 of 204 infants (6%). Multiple potential predictors were associated with IS, including Apgar scores, EEG features, seizure characteristics, MRI abnormalities, and clinical status at hospital discharge. The final model included three risk factors: (a) severely abnormal EEG or ≥3 days with seizures recorded on EEG, (b) deep gray or brainstem injury on MRI, and (c) abnormal tone on discharge exam. The stratified risk of IS was the following: no factors 0% (0/82, 95% confidence interval [CI] 0%-4%), one or two factors 4% (4/108, 95% CI 1%-9%), and all three factors 57% (8/14, 95% CI 29%-83%).

SIGNIFICANCE

IS risk after acute symptomatic neonatal seizures can be stratified using commonly available clinical data. No child without risk factors, vs >50% of those with all three factors, developed IS. This risk prediction rule may be valuable for clinical counseling as well as for selecting participants for clinical trials to prevent post-neonatal epilepsy. This tailored approach may lead to earlier diagnosis and treatment and improve outcomes for a devastating early life epilepsy.

Management of Infantile Spasms During the COVID-19 Pandemic

Circumstances of the COVID-19 pandemic have mandated a change to standard management of infantile spasms. On April 6, 2020, the Child Neurology Society issued an online statement of immediate recommendations to streamline diagnosis and treatment of infantile spasms with utilization of telemedicine, outpatient studies, and selection of first-line oral therapies as initial treatment. The rationale for the recommendations and specific guidance including follow-up assessment are provided in this manuscript. These recommendations are indicated as enduring if intended to outlast the pandemic, and limited if intended only for the pandemic health care crisis but may be applicable to future disruptions of health care delivery.

Impact of therapeutic hypothermia on infantile spasms: an observational cohort study

AIM

To establish the incidence of infantile spasms in children in the southern region of the Republic of Ireland and to compare the incidence of infantile spasms before and after the introduction of therapeutic hypothermia in infants with hypoxic-ischemic encephalopathy (HIE).

METHOD

Children born between 2003 and 2015 and diagnosed with infantile spasms (epileptic spasms with or without hypsarrhythmia) in the first 2 years of life were identified through audits of electroencephalography reports and paediatric neurology patient lists. Data on live births were obtained from the regional hospital statistics databases. Medical charts of infantile spasm cases were reviewed for demographic information, diagnostic workup results, treatment response, disease course, and developmental outcome.

RESULTS

Forty-two infants with infantile spasms were identified. The cumulative incidence of infantile spasms up to the age of 2 years was 4.01 per 10 000 live births. Difference due to sex was minimal (22 males, 20 females) and most infants were delivered at or near term with gestational ages ranging between 30.0 and 41.8 weeks (median [interquartile range] 39.6wks [38.1-40.0wks]). The aetiology for infantile spasms was identified in almost two-thirds of cases, with HIE being the single most common cause (n=7). Other causes included chromosomal and monogenetic abnormalities (n=8). Infantile spasms occurred in moderate and severe grades of HIE, with a significantly higher incidence in those with severe HIE (p=0.029). Infants with severe HIE who did not receive therapeutic hypothermia were six times more likely to develop infantile spasms compared to those who did, but the difference was not statistically significant (4 out of 16 vs 1 out of 24, p=0.138).

INTERPRETATION

This study provides detailed information about infantile spasms before and after the introduction of therapeutic hypothermia. HIE severity is a risk factor for the development of infantile spasms. The introduction of therapeutic hypothermia may have had an impact, but the effect was hard to ascertain in this cohort due to the small number of infants.

WHAT THIS PAPER ADDS

The incidence of infantile spasms and patient characteristics in the southern region of the Republic of Ireland is similar to internationally published data. None of the infants with a history of mild hypoxic-ischemic encephalopathy (HIE) developed infantile spasms. The risk of infantile spasms was higher in infants with severe HIE. Infantile spasms were more frequent in infants with severe HIE not treated with therapeutic hypothermia.

Epileptic Spasms Predict Poor Epilepsy Outcomes After Perinatal Stroke

Perinatal stroke is a significant cause of severe epilepsy, including epileptic spasms. Although epileptic spasms due to underlying structural lesion often respond poorly to treatment and evolve into drug-resistant epilepsy, outcomes are not uniformly poor, and predictors of outcomes are not well described. We performed a single-institution retrospective review of epileptic spasms following perinatal stroke to determine if outcome depended on vascular subtype. We identified 24 children with epileptic spasms due to perinatal ischemic stroke: 11 cases of perinatal arterial stroke and 13 cases of perinatal venous infarct. Initial response to treatment was similar between groups; however, although children with perinatal arterial stroke who responded to epileptic spasms therapy had high rates of seizure freedom, many children with perinatal venous infarct, regardless of initial response, had residual drug-resistant epilepsy. We consider whether the mechanism for epileptogenesis may be different between arterial and venous strokes, and whether these 2 groups should be monitored for epileptic spasms, and subsequent epilepsy, differently.

Correlation Between White Matter Injury Identified by Neonatal Diffusion Tensor Imaging and Neurodevelopmental Outcomes Following Term Neonatal Asphyxia and Therapeutic Hypothermia: An Exploratory Pilot Study

AIM

Hypoxic-ischemic encephalopathy is associated with damage to deep gray matter; however, white matter involvement has become recognized. This study explored differences between patients and clinical controls on diffusion tensor imaging, and relationships between diffusion tensor imaging and neurodevelopmental outcomes.

METHOD

Diffusion tensor imaging was obtained for 31 neonates after hypoxic-ischemic encephalopathy treated with therapeutic hypothermia and 10 clinical controls. A subgroup of patients with hypoxic-ischemic encephalopathy (n = 14) had neurodevelopmental outcomes correlated with diffusion tensor imaging scalars.

RESULTS

Group differences in diffusion tensor imaging scalars were observed in the putamen, anterior and posterior centrum semiovale, and the splenium of the corpus callosum. Differences in these regions of interest were correlated with neurodevelopmental outcomes between ages 20 and 32 months.

CONCLUSION

Therapeutic hypothermia may not be a complete intervention for hypoxic-ischemic encephalopathy, as neonatal white matter changes may continue to be evident, but further research is warranted. Patterns of white matter change on neonatal diffusion tensor imaging correlated with neurodevelopmental outcomes in this exploratory pilot study.

Clinical, Neuroimaging, and Electrographic Predictors of Phenobarbital Failure in Newborns With Hypoxic Ischemic Encephalopathy and Seizures

BACKGROUND

Many neonates with hypoxic ischemic encephalopathy and seizures do not respond to the first line antiepileptic drug, phenobarbital. Little is known about what factors are associated with its failure.

OBJECTIVE

To examine factors associated with failure of phenobarbital therapy in neonates with hypoxic ischemic encephalopathy and seizures.

DESIGN/METHODS

A single-center retrospective review of 50 term (>35 weeks) neonates with hypoxic ischemic encephalopathy and seizures treated with phenobarbital as the first-line antiepileptic. Neonates were classified into either responders (n = 30) or nonresponders (n = 20). Nonresponse was defined as continued seizures after maximum dosing of phenobarbital or an additional antiepileptic. Subjects with acceptable magnetic resonance imaging (MRI) scans obtained within 2 weeks of birth were included in the study and rated using an MRI injury scoring system. Charts were reviewed for demographic, clinical, and laboratory variables. Resuscitation and seizure scores were also calculated. Electroencephalographic (EEG) background activity was reviewed in 2 different time epochs (12-24 hours and 24-36 hours of life) and graded as per ACNS guidelines.

RESULTS

There were no significant group differences in demographic, clinical, and laboratory variables except nonresponders, who had higher mean seizure score (P = .01) and significantly more injury on MRI scan for white matter (P = .004), parenchymal cortex (P = .027), and watershed (P = .009) regions. Neonates with moderately abnormal or severely abnormal background EEG responded poorly to phenobarbital.

CONCLUSION

In the presence of above factors, one can anticipate that additional antiepileptic medication may be needed. These data also support that larger studies should be done to look prospectively at using alternative agents first line in patients with severe injury.

Seizure classification, etiology, and management

The first weeks of life are a time of heightened risk for seizures due to age-dependent physiologic features of the developing brain that lead to increased neuronal excitation and decreased inhibition. Usually, seizures in neonates are a symptom of an acute brain injury; seizures are only rarely due to neonatal-onset epilepsy syndromes. Neonatal seizures are harmful to the developing brain; early and accurate diagnosis is critical. For suspected seizures, EEG monitoring should be initiated as soon as is feasible, in order to evaluate for events of concern, screen for subclinical seizures, and assess the EEG background. Amplitude-integrated EEG can provide excellent complementary data, particularly with regard to evolution of background patterns, but has limited sensitivity to detect individual neonatal seizures. An urgent and systematic approach to precise etiologic diagnosis is key for optimal management and estimates of prognosis. Evaluation of the seizure etiology must occur in parallel with initiation of appropriate treatment. It is critical that neonatologists and neurologists develop hospital-specific, consensus-based practice pathways for neonatal seizure evaluation and treatment. Such practice pathways can streamline medical decision making, facilitate rapid medication administration, and potentially decrease seizure burden and optimize outcomes. Herein, the pathophysiology, epidemiology, treatment, and long-term management considerations for neonatal seizures are presented.

Outcomes After Acute Symptomatic Seizures in Children Admitted to a Neonatal Neurocritical Care Service

BACKGROUND

Neonatal seizures due to acute brain injury are associated with high rates of death, disability, and epilepsy. Our objective was to examine incidence of and risk factors for epilepsy among survivors of acute symptomatic neonatal seizures who were cared for by a neonatal neurocritical care service.

METHODS

Neonates with acute symptomatic seizures who were admitted to UCSF Benioff Children's Hospital Neuro-Intensive Care Nursery from July 2008 to June 2014 were considered for inclusion.

RESULTS

A total of 144 children with acute symptomatic seizures met study criteria and 37 (26%) died before age one. Eighty-seven children (85% of eligible survivors) were followed up to one year or longer. Epilepsy was diagnosed in eight children at median age 4.9 (interquartile range 1.7, 6.1) years. The cumulative incidence risk of epilepsy at one year was 2% (95% confidence interval 0.6% to 9%) and at five years was 7% (95% confidence interval 3% to 20%). Cerebral palsy was diagnosed in 21%. Bayley-III cognitive subscale less than 85 was present in 13%. Children with epilepsy were more likely to be preterm, have brain injury, and be discharged home on antiseizure medication, although the results were not significant after adjusted analysis.

CONCLUSIONS

The risk of epilepsy was lower and age at onset was older than in previous reports, which may be related to multiple factors including a neurocritical care approach, treatment of hypoxic-ischemic encephalopathy with hypothermia, high rate of neonatal transition to palliative care, and the exclusion of neonatal onset epilepsies. Continuation of antiseizure medications in infancy did not decrease the risk of epilepsy. Long-term, multicenter studies are needed to understand whether neonatal seizure management can alter the risk of epilepsy.

Outcomes after acute symptomatic seizures in neonates

Acute symptomatic seizures are a common sign of neurological dysfunction and brain injury in neonates and occur in approximately one to three per 1000 live births. Seizures in neonates are usually a sign of underlying brain injury and, as such, are commonly associated with adverse outcomes. Neurological morbidities in survivors often co-occur; epilepsy, cerebral palsy, and intellectual disability often occur together in the most severely affected children. Risk factors for adverse outcome include prematurity, low Apgar scores, low pH on the first day of life, seizure onset <24 or >72 h after birth, abnormal neonatal neurological examination, abnormal neonatal electroencephalographic background, status epilepticus, and presence and pattern of brain injury (particularly deep gray or brainstem injury). Despite this list of potential indicators, accurate prediction of outcome in a given child remains challenging. There is great need for long-term, multicenter studies to examine risk factors for, and pathogenesis of, adverse outcomes following acute symptomatic seizures in neonates.

Detailed Magnetic Resonance Imaging (MRI) Analysis in Infantile Spasms

PURPOSE

To evaluate initial magnetic resonance imaging (MRI) abnormalities in infantile spasms, correlate them to clinical characteristics, and describe repeat imaging findings.

METHODS

A retrospective review of infantile spasm patients was conducted, classifying abnormal MRI into developmental, acquired, and nonspecific subgroups.

RESULTS

MRIs were abnormal in 52 of 71 infantile spasm patients (23 developmental, 23 acquired, and 6 nonspecific) with no correlation to the clinical infantile spasm characteristics. Both developmental and acquired subgroups exhibited cortical gray and/or white matter abnormalities. Additional abnormalities of deep gray structures, brain stem, callosum, and volume loss occurred in the structural acquired subgroup. Repeat MRI showed better definition of the extent of existing malformations.

CONCLUSION

In structural infantile spasms, developmental/acquired subgroups showed differences in pattern of MRI abnormalities but did not correlate with clinical characteristics.

In Vivo Multimodal Magnetic Resonance Imaging Changes After N-Methyl-d-Aspartate-Triggered Spasms in Infant Rats

Objective

Despite the serious neurodevelopmental sequelae of epileptic encephalopathy during infancy, the pathomechanisms involved remain unclear. To find potential biomarkers that can reflect the pathogenesis of epileptic encephalopathy, we explored the neurometabolic and microstructural sequelae after infantile spasms using a rat model of infantile spasms and in vivo magnetic resonance imaging techniques.

Methods

Rats prenatally exposed to betamethasone were subjected to three rounds of intraperitoneal N-methyl-d-aspartate (NMDA) triggering of spasms or received saline injections (controls) on postnatal days (P) 12, 13, and 15. Chemical exchange saturation transfer imaging of glutamate (GluCEST) were performed at P15 and 22 and diffusion tensor imaging and additional spectroscopy (1H-MRI/MRS) of the cingulate cortex were serially done at P16, 23, and 30 and analyzed. Pathological analysis and western blotting were performed with rats sacrificed on P35.

Results

Within 24 h of the three rounds of NMDA-induced spasms, there was an acute increase in the GluCEST (%) in the cortex, hippocampus, and striatum. When focused on the cingulate cortex, mean diffusivity (MD) was significantly decreased during the acute period after multiple spasms with an increase in γ-aminobutyric acid (GABA), glutamate, and glutamine N-acetylaspartate-plus-N-acetylaspartylglutamate (tNAA), total choline, and total creatine. The juvenile rats also showed decreased MD on diffusion tensor imaging and significant decreases in taurine, tNAA, and macromolecules-plus-lipids in the cingulate cortex. Pathologically, there was a significant reduction in glial fibrillary acidic protein, myelin basic protein, and neuronal nuclei expression in the cingulate cortex of rats with NMDA-induced spasms.

Significance

These neurometabolic and microstructural alterations after NMDA-triggered spasms might be potential imaging biomarkers of epileptic encephalopathy.

Levetiracetam for the Treatment of Seizures in Neonatal Hypoxic Ischemic Encephalopathy

The objective of this study was to determine the efficacy and safety of levetiracetam in treatment of neonatal seizures due to hypoxic ischemic encephalopathy. Seizures often persist in neonates with hypoxic ischemic encephalopathy despite phenobarbital. A retrospective single-center study was conducted in neonates ≥36 weeks gestation with hypoxic ischemic encephalopathy. A total of 127 neonates were identified born 2008-2015. Clinical seizures occurred in 83 infants. Fifty-one neonates (61%) had cessation of seizures with only phenobarbital. Thirty-two neonates received levetiracetam after phenobarbital, and the seizures stopped in 27 of these neonates. The mean total loading dose of levetiracetam was 63 mg/kg. Mean maintenance dose of levetiracetam was 65 mg/kg/d. We found no negative side effects in neonates following levetiracetam use. Our study finds that levetiracetam is an efficacious medication in treatment of seizures in the setting of neonatal hypoxic ischemic encephalopathy. Future prospective studies should explore its use as a first-line medication.

The Vulnerable Newborn Brain: Imaging Patterns of Acquired Perinatal Injury

BACKGROUND

Over the past two decades, imaging techniques have allowed for better visualization of the newborn brain. This has enabled us to detect patterns, understand mechanisms and guide diagnosis and treatment.

OBJECTIVES

The purpose of this review is to discuss imaging characteristics of acquired perinatal brain injury.

METHODS

Through literature review and the author's research, this review assesses published data on the distinct imaging patterns that occur in the neonatal period due to acquired brain insults.

RESULTS

In the term brain, susceptibility to hypoxia-ischemia, hypoglycemia and hyperbilirubinemia results in unique patterns of injury. Stroke commonly occurs in the newborn period. Infections, especially viral, have distinct patterns of white matter injury. In the preterm brain, white matter injury occurs commonly and is affected by postnatal growth, stress and infection. The cerebellum is uniquely vulnerable during this period, with resultant hemorrhages in almost half of preterm infants. Cerebellar growth is affected by intraventricular hemorrhage, drugs and placental pathology. Periventricular hemorrhagic infarction is the most serious consequence of the spectrum of intraventricular hemorrhage and results in profound disabilities.

CONCLUSIONS

Taken together, the acquired perinatal brain injuries can have lifelong devastating consequences, so the search for therapies must continue.

Altered regional homogeneity in epileptic patients with infantile spasm: A resting-state fMRI study

Infantile spasm (IS) syndrome is an age-related epileptic encephalopathy that occurs in children. The purpose of this study was to investigate regional homogeneity (ReHo) changes in IS patients. Resting-state fMRI was performed on 11 patients with IS, along with 35 age- and sex-matched healthy subjects. Group comparisons between the two groups demonstrate that the pattern of regional synchronization synchronization in IS patients is changed. Decreased ReHo values were found in default mode network, bilateral motor-related areas and left occipital gyrus of the patient group. Increased ReHo was found in regions of cingulum, cerebellum, supplementary motor area and brain deep nucleus, such as hippocampus, caudate, thalamus and insula. The significant differences might indicate that epileptic action have some injurious effects on the motor, executive and cognitive related regions. In addition, ReHo values of left precuneus and right superior frontal gyrus were associated with the epilepsy duration in the IS group. The correlation results indicate that the involvement of these regions may be related to the seizure generation. Our results suggest that IS may have an injurious effect on the brain activation. The findings may shed new light on the understanding the neural mechanism of IS epilepsy.

Early Anatomical Injury Patterns Predict Epilepsy in Head Cooled Neonates With Hypoxic-Ischemic Encephalopathy

BACKGROUND

Our aim was to determine whether early anatomical injury patterns on magnetic resonance imaging-correlate with the development of postneonatal epilepsy in infants treated with selective head cooling for hypoxic-ischemic encephalopathy.

METHODS

We retrospectively analyzed infants ≥35 weeks' gestation born between 2008 and 2013 and followed for at least one year at Northwestern University. All had brain magnetic resonance imaging scans at days 4-5 and electroencephalographs during rewarming and at 3 to 6 months of age.

RESULTS

Outcome was favorable for our cohort of 73 individuals with a mean follow-up of 41 (±7) months. The majority (66%) survived with no seizure recurrence, whereas 13 (18%) developed postneonatal epilepsy, including eight who had infantile spasms. Twelve infants (16%) died. The most common magnetic resonance imaging pattern was diffuse brain injury involving both cortical and subcortical gray matter (26/73, 35%), followed by cortical and subcortical white matter injury (18/73, 25%) and normal magnetic resonance imaging (16/73, 22%). In 13 infants (18%), the brainstem was involved in addition to cortical and subcortical gray matter; nine died and all four surviving infants developed infantile spasms. All 18 infants with cortical and subcortical white matter injury survived and none developed postneonatal epilepsy. The risk of postneonatal epilepsy was associated with injury involving subcortical regions (basal ganglia, thalamus ± brainstem) (12/39 versus 1/34, P < 0.003).

CONCLUSIONS

Brainstem injury was highly predictive of infantile spasms, whereas cortical injury alone predicted low risk for short-term postneonatal epilepsy. Location of anatomical injury on magnetic resonance imaging can be an early predictive factor for development of infantile spasms and inform prognostic decisions in newborns treated with selective head cooling for hypoxic-ischemic encephalopathy.

Infraslow EEG changes in infantile spasms

PURPOSE

Infantile spasms (IS) are a devastating epileptic encephalopathy syndrome of infancy. Analysis of infraslow EEG activity (ISA) has shown potential in the presurgical evaluation of patients with epilepsy and in differentiating between focal and generalized epilepsy syndromes. Infraslow EEG activity analysis may provide insights into the pathophysiology of some difficult-to-treat epilepsy syndromes, such as IS. To our knowledge, there are no published reports describing ISA in patients with IS. The purpose of this study was to describe ictal patterns of ISA in patients with IS and to correlate with clinical data.

METHODS

EEG recordings of all cases of IS in the past 10 years at the Alberta Children's Hospital were reviewed. Inclusion criteria were a technically adequate video EEG recording that captured at least one spasm. For each patient, the first 10 confirmed spasms were examined. Spasms were evaluated for changes in ISA, which were either generalized, lateralized, or absent ISA (g-ISA, l-ISA, or n-ISA, respectively). Results were correlated with treatments, clinical course, and information pertinent to likely etiology of the IS.

RESULTS

A total of 77% of spasms were associated with ISA; 57% with g-ISA, 20% l-ISA, and 21% n-ISA. All patients with exclusively g-ISA showed at least a partial response to initial therapy, while this was the case in 66.7% of those with at least some l-ISA and 50% of those with exclusively n-ISA. Other seizure types occurred in 60% of patients with exclusively g-ISA versus 83% with some l-ISA and all patients with exclusively n-ISA.

CONCLUSIONS

Ictal ISA was observed in the majority of IS. Trends were observed suggesting that the presence of exclusive g-ISA changes may be a positive prognostic factor in IS.