Pre-surgical mapping of eloquent cortex for paediatric epilepsy surgery candidates: Evidence from a review of advanced functional neuroimaging.

PURPOSE: A review of all published evidence for mapping eloquent (motor, language and memory) cortex using advanced functional neuroimaging (functional magnetic resonance imaging [fMRI] and magnetoencephalography [MEG]) for paediatric epilepsy surgery candidates has not been conducted previously. Research in this area has predominantly been in adult populations and applicability of these techniques to paediatric populations is less established. METHODS: A review was performed using an advanced systematic search and retrieval of all published papers examining the use of functional neuroimaging for paediatric epilepsy surgery candidates. RESULTS: Of the 2724 papers retrieved, 34 met the inclusion criteria. Total paediatric participants identified were 353 with an age range of 5 months-19 years. Sample sizes and comparisons with alternative investigations to validate techniques are small and variable paradigms are used. Sensitivity 0.72 (95% CI 0.52-0.86) and specificity 0.60 (95% CI 0.35-0.92) values with a Positive Predictive Value of 74% (95% CI 61-87) and a Negative Predictive Value of 65% (95% CI 52-78) for fMRI language lateralisation with validation, were obtained. Retrieved studies indicate evidence that both fMRI and MEG are able to provide information lateralising and localising motor and language functions. CONCLUSIONS: A striking finding of the review is the paucity of studies (n=34) focusing on the paediatric epilepsy surgery population. For children, it remains unclear which language and memory paradigms produce optimal activation and how these should be quantified in a statistically robust manner. Consensus needs to be achieved for statistical analyses and the uniformity and yield of language, motor and memory paradigms. Larger scale studies are required to produce patient series data which clinicians may refer to interpret results objectively. If functional imaging techniques are to be the viable alternative for pre-surgical mapping of eloquent cortex for children, paradigms and analyses demonstrating concordance with independent measures must be developed.

Idiopathic focal epilepsies: the "lost tribe".

The term idiopathic focal epilepsies of childhood (IFE) is not formally recognised by the ILAE in its 2010 revision (Berg et al., 2010), nor are its members and boundaries precisely delineated. The IFEs are amongst the most commonly encountered epilepsy syndromes affecting children. They are fascinating disorders that hold many "treats" for both clinicians and researchers. For example, the IFEs pose many of the most interesting questions central to epileptology: how are functional brain networks involved in the manifestation of epilepsy? What are the shared mechanisms of comorbidity between epilepsy and neurodevelopmental disorders? How do focal EEG discharges impact cognitive functioning? What explains the age-related expression of these syndromes? Why are EEG discharges and seizures so tightly locked to slow-wave sleep? In the last few decades, the clinical symptomatology and the respective courses of many IFEs have been described, although they are still not widely appreciated beyond the specialist community. Most neurologists would recognise the core syndromes of IFE to comprise: benign epilepsy of childhood with centro-temporal spikes or Rolandic epilepsy (BECTS/RE); Panayiotopoulos syndrome; and the idiopathic occipital epilepsies (Gastaut and photosensitive types). The Landau-Kleffner syndrome and the related (idiopathic) epilepsy with continuous spikes and waves in sleep (CSWS or ESES) are also often included, both as a consequence of the shared morphology of the interictal discharges and their potential evolution from core syndromes, for example, CSWS from BECTS. Atypical benign focal epilepsy of childhood also has shared electro-clinical features warranting inclusion. In addition, a number of less well-defined syndromes of IFE have been proposed, including benign childhood seizures with affective symptoms, benign childhood epilepsy with parietal spikes, benign childhood seizures with frontal or midline spikes, and benign focal seizures of adolescence. The term "benign" is often used in connection with the IFEs and is increasingly being challenged. Certainly most of these disorders are not associated with the devastating cognitive and behavioural problems seen with early childhood epileptic encephalopathies, such as West or Dravet syndromes. However, it is clear that specific, and sometimes persistent, neuropsychological deficits in attention, language and literacy accompany many of the IFEs that, when multiplied by the large numbers affected, make up a significant public health problem. Understanding the nature, distribution, evolution, risk and management of these is an important area of current research. A corollary to such questions regarding comorbidities is the role of focal interictal spikes and their enduring impact on cognitive functioning. What explains the paradox that epilepsies characterised by abundant interictal epileptiform abnormalities are often associated with very few clinical seizures? This is an exciting area in both clinical and experimental arenas and will eventually have important implications for clinical management of the whole child, taking into account not just seizures, but also adaptive functioning and quality of life. For several decades, we have accepted an evidence-free approach to using or not using antiepileptic drugs in IFEs. There is huge international variation and only a handful of studies examining neurocognitive outcomes. Clearly, this is a situation ready for an overhaul in practice. Fundamental to understanding treatment is knowledge of aetiology. In recent years, there have been several significant discoveries in IFEs from studies of copy number variation, exome sequencing, and linkage that prompt reconsideration of the "unknown cause" classification and strongly suggest a genetic aetiology. The IFE are strongly age-related, both with regards to age of seizure onset and remission. Does this time window solely relate to a similar age-related gene expression, or are there epigenetic factors involved that might also explain low observed twin concordance? The genetic (and epigenetic) models for different IFEs, their comorbidities, and their similarities to other neurodevelopmental disorders deserve investigation in the coming years. In so doing, we will probably learn much about normal brain functioning. This is because these disorders, perhaps more than any other human brain disease, are disorders of functional brain systems (even though these functional networks may not yet be fully defined). In June 2012, an international group of clinical and basic science researchers met in London under the auspices of the Waterloo Foundation to discuss and debate these issues in relation to IFEs. This Waterloo Foundation Symposium on the Idiopathic Focal Epilepsies: Phenotype to Genotype witnessed presentations that explored the clinical phenomenology, phenotypes and endophenotypes, and genetic approaches to investigation of these disorders. In parallel, the impact of these epilepsies on children and their families was reviewed. The papers in this supplement are based upon these presentations. They represent an updated state-of-the-art thinking on the topics explored. The symposium led to the formation of international working groups under the umbrella of "Luke's Idiopathic Focal Epilepsy Project" to investigate various aspects of the idiopathic focal epilepsies including: semiology and classification, genetics, cognition, sleep, high-frequency oscillations, and parental resources (see www.childhood-epilepsy.org). The next sponsored international workshop, in June 2014, was on randomised controlled trials in IFEs and overnight learning outcome measures.

Corticosteroids including ACTH for childhood epilepsy other than epileptic spasms.

BACKGROUND: This is an updated version of the original Cochrane review published in Issue 1, 2007.Epilepsy is a disorder with recurrent epileptic seizures. Corticosteroids have been used in the treatment of children with epilepsy and have significant adverse effects. Their efficacy and tolerability have not been clearly established. OBJECTIVES: To determine the efficacy, in terms of seizure control, improvements in cognition and in quality of life and tolerability of steroids compared to placebo or other antiepileptic drugs in children with epilepsy, excluding epileptic spasms. SEARCH METHODS: We searched the following databases: The Cochrane Epilepsy Group Specialized Register (1 August 2014); CENTRAL, (The Cochrane Library Issue 7, July 2014); MEDLINE (1946 to 1 August 2014); EMBASE (1966 to December 2004); Database of Abstracts of Reviews of Effectiveness (DARE; Issue 3 of the database published in The Cochrane Library Issue 7, July 2014); ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform ICTRP (1 August 2014).We checked the reference lists of retrieved studies for additional reports of relevant studies. SELECTION CRITERIA: All randomised controlled trials of administration of corticosteroids to children (less than 16 years) with epilepsy. DATA COLLECTION AND ANALYSIS: For this update two review authors independently selected trials for inclusion and extracted data. Outcomes included cessation of seizures, reduction in seizure frequency, improvement in cognition, quality of life and adverse effects of steroids. MAIN RESULTS: A single RCT was included that recruited five children in a double blind cross-over trial. One child was withdrawn prematurely from the study and another had infantile spasms and hence was excluded from further analysis. Adrenocorticotrophin hormone (ACTH 4-9) was administered. Of the three children analysed, one showed a reduction in seizures of 25% to 50% at both the low and higher doses of corticosteroids compared to placebo; one child showed a reduction in seizures at the higher dose only and one child showed no reduction in seizures at either dose. No adverse effects were reported. AUTHORS' CONCLUSIONS: Since the last version of this review no new evidence has been found for the efficacy of corticosteroids in treating childhood epilepsies. Clinicians using steroids in childhood epilepsies, other than for epileptic spasms, should take this into account before using these agents.

Monitoring the changing pattern of delivery of paediatric epilepsy surgery in England--an audit of a regional service and examination of national trends.

PURPOSE: The demand for paediatric epilepsy surgery in the UK greatly exceeds the number of operations performed. Hence, Children's Epilepsy Surgery Service (CESS) was commenced in 2012. This study is aimed to characterise the changes in service delivery in the North East of England Paediatric Neuroscience Network and nationally. METHODS: A retrospective cohort study of paediatric epilepsy surgery in Leeds between 2005 and 2012 is presented followed by analysis of British Paediatric Neurosurgical Group (BPNG) data before and after CESS commissioning. RESULTS: During the study period, 42 children underwent epilepsy surgery in Leeds. The commonest aetiologies were neoplasm (33%), focal cortical dysplasia (19%) and mesial temporal sclerosis (19%). Seizure outcome was 71 % EngelI and 83% EngelI+II. Complications included one infection (2%), two temporary (5%) and one permanent (2%) motor deficits, three new/worsened visual field deficits (7%). There were six re-craniotomies (14%). The BPNG data show a 48% increase in paediatric epilepsy surgery in England between 2009 (90 cases) and 2012 (133 cases), and a 20% fall in 2013 (106 cases)--the first calendar year for CESS. On average, 64% of all operations were performed in London. CONCLUSIONS: The number of children receiving surgery for epilepsy in England had increased annually up to, and declined after, the establishment of CESS centres. The yearly caseload in neurosurgical units outside of London is small. The outcomes from Leeds are comparable to those published elsewhere. Other UK units are encouraged to publish outcomes to facilitate patient, commissioner and provider decision making.

Antiepileptic drug treatment of rolandic epilepsy and Panayiotopoulos syndrome: clinical practice survey and clinical trial feasibility.

BACKGROUND: The evidence base for management of childhood epilepsy is poor, especially for the most common specific syndromes such as rolandic epilepsy (RE) and Panayiotopoulos syndrome (PS). Considerable international variation in management and controversy about non-treatment indicate the need for high quality randomised controlled trials (RCT). The aim of this study is, therefore, to describe current UK practice and explore the feasibility of different RCT designs for RE and PS. METHODS: We conducted an online survey of 590 UK paediatricians who treat epilepsy. Thirty-two questions covered annual caseload, investigation and management practice, factors influencing treatment, antiepileptic drug preferences and hypothetical trial design preferences. RESULTS: 132 responded (22%): 81% were paediatricians and 95% at consultant seniority. We estimated, annually, 751 new RE cases and 233 PS cases. Electroencephalography (EEG) is requested at least half the time in approximately 70% of cases; MRI brain at least half the time in 40%-65% cases and neuropsychological evaluation in 7%-8%. Clinicians reported non-treatment in 40%: main reasons were low frequency of seizures and parent/child preferences. Carbamazepine is the preferred older, and levetiracetam the preferred newer, RCT arm. Approximately one-half considered active and placebo designs acceptable, choosing seizures as primary and cognitive/behavioural measures as secondary outcomes. CONCLUSIONS: Management among respondents is broadly in line with national guidance, although with possible overuse of brain imaging and underuse of EEG and neuropsychological assessments. A large proportion of patients in the UK remains untreated, and clinicians seem amenable to a range of RCT designs, with carbamazepine and levetiracetam the preferred active drugs.

Guidelines, training, audit, and quality standards in children's epilepsy services: closing the loop.

There has been considerable evolution in epilepsy healthcare for children over the last decade in the United Kingdom. There has been no single explanation for this. The development of national clinical guidelines, locally delivered but nationally designed educational programmes, nation-wide clinical audit, clinical networks and development of designated services have all had complimentary roles in enabling the implementation of national recommendations for the development of epilepsy care. These models may be applicable to other healthcare settings outside the UK.

Experience of mechanical thrombectomy for paediatric arterial ischaemic stroke.

BACKGROUND: Paediatric arterial ischaemic stroke (AIS) is an important cause of acute neurological symptoms in children, it causes significant morbidity and is one of the top ten causes of childhood deaths. Consensus papers have suggested guidelines for the management of AIS in childhood, although none recommend thrombectomy. Despite this, children within our institution have undergone mechanical thrombectomy for large vessel occlusion. This is the first series of mechanical thrombectomy and outcomes performed in children in the U.K. METHODS: We describe the endovascular management of paediatric arterial ischaemic stroke (AIS) in four children (5-15 years) with PedNIHSS > 17. RESULTS: Three had basilar artery (BA) occlusion and one left middle cerebral artery (MCA) occlusion. All underwent uncomplicated thrombectomy followed by intravenous heparin. One had a successful second attempt. The BA cases underwent thrombectomy 17-36 h after symptom onset; the left MCA case <6 h after symptom onset. Modified Rankin Scale (MRS) was 0-3, 50% had MRS 0. DISCUSSION: Adult AIS guidelines recommend IV recombinant tissue plasminogen activator (r-tPA) within 4.5 h of onset and intra-arterial r-tPA within 6 h; thrombectomy being reserved for carefully selected patients. Paediatric AIS recognition is problematic, often with delayed imaging. There is little evidence regarding efficacy of thrombectomy for paediatric AIS. Our experience suggests there may be a role for endovascular clot retrieval in selected patients managed by an experienced multidisciplinary team. Careful data collection is mandatory.

A pilot of clinical performance indicators for suspected childhood epilepsies.

PURPOSE: In response to continuing concerns regarding the quality and equality of care for children and young people, the British Paediatric Neurology Association (BPNA) has supported the development of practical and meaningful audit to support quality improvement. METHOD: In 2006, the Children's Epilepsy Workstream in Trent (CEWT) coordinated a retrospective multi-service audit of paediatric epilepsy care against NICE and SIGN guidelines. This aimed to both facilitate quality improvements for participating services and act as a pilot for future potential national audits. RESULTS: The audit was achieved in 4 hospital services using prospective and retrospective ascertainment methods. 12 performance indicators were applied to each cohort. Overall 54% (12/22) of children with epilepsy had input from a paediatrician with "expertise" and 23% (5/22) had input from an epilepsy specialist nurse. CONCLUSION: Audit can be developed for epilepsies that delivers standardised quality metrics against national recommendations. As well as supporting local quality improvement initiatives, comparative and aggregate data can be produced to potentially give regional and national perspectives. The results and experience describe the journey towards the 2009-2012 Epilepsy 12 UK multicentre epilepsy audit.

The clinical utility of an SCN1A genetic diagnosis in infantile-onset epilepsy.

AIM: Genetic testing in the epilepsies is becoming an increasingly accessible clinical tool. Mutations in the sodium channel alpha 1 subunit (SCN1A) gene are most notably associated with Dravet syndrome. This is the first study to assess the impact of SCN1A testing on patient management from both carer and physician perspectives. METHOD: Participants were identified prospectively from referrals to the Epilepsy Genetics Service in Glasgow and contacted via their referring clinicians. Questionnaires exploring the consequences of SCN1A genetic testing for each case were sent to carers and physicians. RESULTS: Of the 244 individuals contacted, 182 (75%) carried a SCN1A mutation. Carers of 187 (77%) patients responded (90 females, 97 males; mean age at referral 4 y 10 mo; interquartile range 9 y 1 mo). Of those participants whose children tested positive for a mutation, 87% reported that genetic testing was helpful, leading to treatment changes resulting in fewer seizures and improved access to therapies and respite care. Out of 187 physicians, 163 responded (87%), of whom 48% reported that a positive test facilitated diagnosis earlier than with clinical and electroencephalography data alone. It prevented additional investigations in 67% of patients, altered treatment approach in 69%, influenced medication choice in 74%, and, through medication change, improved seizure control in 42%. INTERPRETATION: In addition to confirming a clinical diagnosis, a positive SCN1A test result influenced treatment choice and assisted in accessing additional therapies, especially in the very young.

Syncope-like epileptic seizures in Panayiotopoulos syndrome.

OBJECTIVE: To describe the clinical features of syncope-like epileptic seizures (SLES) and their frequency in Panayiotopoulos syndrome (PS). METHODS: This was a 6-year prospective study of all children aged 1-15 years referred for an EEG. PS was defined by the occurrence of at least one autonomic seizure (AS) in a neurodevelopmentally normal child and at least one EEG with focal spikes. SLES were defined as self-terminating events of sudden loss of postural tone and unresponsiveness, occurring either concurrently with other ictal autonomic symptoms and signs that characterize PS (AS + SLES) or on their own (pure SLES). RESULTS: PS was diagnosed in 33 of 394 consecutive children with at least one afebrile seizure (8.4%). SLES occurred at least once in 17 of 33 children (51.5%); 12 presented SLES in all their AS, and 5 had also AS without SLES. Overall, 53 of 74 AS manifested with SLES (71.6%); 25 were AS + SLES and 28 were pure SLES. The latter occurred in 7 children suddenly and without premonition or obvious triggers while standing, sitting, lying down, or asleep, did not resolve in the horizontal position, and were not associated with stiffening or any involuntary movements, even when longer than a few minutes. Concurrent autonomic symptoms during AS + SLES included emesis, incontinence, mydriasis, miosis, and cardiorespiratory abnormalities. CONCLUSIONS: SLES is a common ictal manifestation of PS and should be considered in the differential diagnosis of suspected syncope, particularly when clinical signs are atypical for neurocardiogenic syncope and the EEG shows focal spikes.

Clinical reasoning and investigations for resective surgery for medically refractory epilepsies in children.

The article presents results of a UK survey of pediatric neurologists' views regarding resective surgery for medically refractory epilepsies in children. In contrast to surveys with adult neurologists, the findings indicate that delays to surgery in the pediatric field are not likely to be due to clinicians' views. There is, however, variability in clinicians' opinions as to what constitutes medically refractory epilepsy, variability in the factors reported as necessary for surgery eligibility, and uncertainty as to how these concepts should be defined. The survey highlights the need for elucidation of the epilepsy surgery process for pediatric patients, clear communication between epilepsy surgery centers and referring neurologists, and dissemination of consensus guidelines relating to the criteria for both medically refractory epilepsy and surgery eligibility.

Recovery of consciousness following acute symptomatic seizures due to central nervous system infections in children.

AIM: The aim of this study was to assess whether acute symptomatic epileptic seizures associated with central nervous system infections (AS(inf) ) have a different ictal and postictal course to seizures of other aetiologies. METHOD: A case note analysis of 81 children (47 males; 34 females; age range 1mo-15y 6mo; median age 12mo) with central nervous system infections was undertaken. Seizure type, duration, aetiology, and timing were recorded. Recovery time to full consciousness in those not intubated was determined. Intubation rates and recovery times were compared with those from previous studies. RESULTS: Of the 81 children, 40 (49.4%) had one or more AS(inf) . The different aetiologies were bacterial meningitis, aseptic meningitis, abscess/empyema, encephalitis, and postoperative infection. Twenty-two had status epilepticus. The intubation rate in children with AS(inf) was higher than that in children with seizures of other aetiologies (21/40 [52.5%] vs 4/124 [3.23%]; p < 0.0001). Median postictal recovery time was 4.33 hours (0-207h). Children with AS(inf) took 4.3 (p<0.01), 3.0 (p=0.004), and 8.8 (p<0.001) times longer to recover than children who had seizures from all causes, remote symptomatic seizures, and febrile seizures respectively. INTERPRETATION: AS(inf) in children are often longer, more likely to be associated with status epilepticus, more likely to necessitate intubation, and take longer to recover from than seizures of other aetiologies. This may help in the early diagnosis of central nervous system infection in children presenting with seizures.

Pathophysiological mechanisms of dominant and recessive GLRA1 mutations in hyperekplexia.

Hyperekplexia is a rare, but potentially fatal, neuromotor disorder characterized by exaggerated startle reflexes and hypertonia in response to sudden, unexpected auditory or tactile stimuli. This disorder is primarily caused by inherited mutations in the genes encoding the glycine receptor (GlyR) alpha1 subunit (GLRA1) and the presynaptic glycine transporter GlyT2 (SLC6A5). In this study, systematic DNA sequencing of GLRA1 in 88 new unrelated human hyperekplexia patients revealed 19 sequence variants in 30 index cases, of which 21 cases were inherited in recessive or compound heterozygote modes. This indicates that recessive hyperekplexia is far more prevalent than previous estimates. From the 19 GLRA1 sequence variants, we have investigated the functional effects of 11 novel and 2 recurrent mutations. The expression levels and functional properties of these hyperekplexia mutants were analyzed using a high-content imaging system and patch-clamp electrophysiology. When expressed in HEK293 cells, either as homomeric alpha1 or heteromeric alpha1beta GlyRs, subcellular localization defects were the major mechanism underlying recessive mutations. However, mutants without trafficking defects typically showed alterations in the glycine sensitivity suggestive of disrupted receptor function. This study also reports the first hyperekplexia mutation associated with a GlyR leak conductance, suggesting tonic channel opening as a new mechanism in neuronal ligand-gated ion channels.

Rufinamide: a new antiepileptic drug treatment for Lennox-Gastaut syndrome.

Lennox-Gastaut syndrome is a relatively rare epilepsy syndrome that usually begins in early-mid childhood and is characterized by multiple seizure types, particularly generalized seizures, which are often resistant to antiepileptic drug medication. Rufinamide is a new antiepileptic drug approved as adjunctive therapy to treat seizures in Lennox-Gastaut syndrome in those 4 years of age and older. In this article, the putative mechanism of action is described, along with data relating to its pharmacokinetics and metabolism. Key findings from clinical trials are presented and discussed. Adverse effects are summarized and compared with those encountered with competitor antiepileptic drugs. Finally, the role of rufinamide in the holistic management of subjects with Lennox-Gastaut syndrome is considered.

Parental and physician beliefs regarding the provision and content of written sudden unexpected death in epilepsy (SUDEP) information.

PURPOSE: The 2007 UK National Institute for Health and Clinical Excellence (NICE) guidelines for epilepsy recommend disclosing the risk of sudden unexpected death in epilepsy (SUDEP) to patients. This recommendation is not undertaken routinely, and considerable variation in individual physician practice exists. Literature indicates wariness of causing distress and anxiety, particularly to children/young people and their families through disclosing a nonpreventable risk. There has been no systematic pediatric study examining parent/guardian information needs and beliefs for risk of SUDEP and its impact on seizure management. It is important to first address these concerns before routinely imparting SUDEP information to parents following NICE recommendations. METHODS: Two questionnaire surveys: a questionnaire examining the provision by pediatric neurologists of SUDEP information, and questionnaires examining parental beliefs and implications at two time points regarding SUDEP information provided in a leaflet. Participants were included in the study if their child had an established diagnosis of epilepsy. Factors for exclusion were single unprovoked seizure, absence seizures, patients in remission, and active discontinuation of treatment. RESULTS: The majority (74%) of pediatric neurologists provided SUDEP information only to a select group of children with epilepsy and were uncertain about the effect such information would have upon the parent and child. Conversely, 91% of parents expected the pediatric neurologist to provide SUDEP risk information. The provision of this information did not have a significant immediate and longer-term negative impact. DISCUSSION: The majority of parents wanted to know about SUDEP and its associated risks. Whenever possible, SUDEP information should be given by the physician accompanied by an information leaflet.

Panayiotopoulos syndrome: an important childhood autonomic epilepsy to be differentiated from occipital epilepsy and acute non-epileptic disorders.

Panayiotopoulos syndrome is a common multifocal autonomic childhood epileptic disorder with significant clinical, pathophysiological and management implications. It affects otherwise normal children with onset at around 3-6 years. It is characterized by seizures, often prolonged, with predominantly autonomic symptoms and mainly ictal vomiting. EEG shows shifting and/or multiple foci, often with occipital dominance. Despite characteristic clinical and EEG manifestations Panayiotopoulos syndrome is often confused with occipital epilepsy and acute non-epileptic disorders such as encephalitis, syncope, cyclic vomiting or atypical migraine. This review aims to describe Panayiotopoulos syndrome on the basis of independent major studies and provide clinical clues for diagnosis and management.