Clinical effectiveness of the psychological therapy Mental Health Intervention for Children with Epilepsy in addition to usual care compared with assessment-enhanced usual care alone: a multicentre, randomised controlled clinical trial in the UK.

BACKGROUND: Mental health difficulties are common in children and young people with chronic health conditions, but many of those in need do not access evidence-based psychological treatments. The study aim was to evaluate the clinical effectiveness of integrated mental health treatment for children and young people with epilepsy, a common chronic health condition known to be associated with a particularly high rate of co-occurring mental health difficulties. METHODS: We conducted a parallel group, multicentre, open-label, randomised controlled trial of participants aged 3-18 years, attending epilepsy clinics across England and Northern Ireland who met diagnostic criteria for a common mental health disorder. Participants were randomised (1:1; using an independent web-based system) to receive the Mental Health Intervention for Children with Epilepsy (MICE) in addition to usual care, or assessment-enhanced usual care alone (control). Children and young people in both groups received a full diagnostic mental health assessment. MICE was a modular psychological intervention designed to treat common mental health conditions in children and young people using evidence-based approaches such as cognitive behaviour therapy and behavioural parenting strategies. Usual care for mental health disorders varied by site but typically included referral to appropriate services. Participants, along with their caregivers, and clinicians were not masked to treatment allocation but statisticians were masked until the point of analysis. The primary outcome, analysed by modified intention-to-treat, was the parent-report Strengths and Difficulties Questionnaire (SDQ) at 6 months post-randomisation. The study is complete and registered with ISRCTN (57823197). FINDINGS: 1401 young people were potentially deemed eligible for study inclusion. Following the exclusion of 531 young people, 870 participants were assessed for eligibility and completed the SDQ, and 480 caregivers provided consent for study inclusion between May 20, 2019, and Jan 31, 2022. Between Aug 28, 2019, and Feb 21, 2022, 334 participants (mean ages 10·5 years [SD 3·6] in the MICE group vs 10·3 [4·0] in control group at baseline) were randomly assigned to an intervention using minimisation balanced by age, primary mental health disorder, diagnosis of intellectual disability, and autistic spectrum disorder at baseline. 168 (50%) of the participants were female and 166 (50%) were male. 166 participants were randomly assigned to the MICE group and 168 were randomly assigned to the control group. At 6 months, the mean SDQ difficulties for the 148 participants in the MICE group was 17·6 (SD 6·3) and 19·6 (6·1) for the 148 participants in the control group. The adjusted effect of MICE was -1·7 (95% CI -2·8 to -0·5; p=0·0040; Cohen's d, 0·3). 14 (8%) patients in the MICE group experienced at least one serious adverse event compared with 24 (14%) in the control group. 68% percent of serious adverse events (50 events) were admission due to seizures. INTERPRETATION: MICE was superior to assessment-enhanced usual care in improving symptoms of emotional and behavioural difficulties in young people with epilepsy and common mental health disorders. The trial therefore shows that mental health comorbidities can be effectively and safely treated by a variety of clinicians, utilising an integrated intervention across ages and in the context of intellectual disability and autism. The evidence from this trial suggests that such a model should be fully embedded in epilepsy services and serves as a model for other chronic health conditions in young people. FUNDING: UK National Institute for Health Research Programme Grants for Applied Research programme and Epilepsy Research UK Endeavour Project Grant.

A novel technique for frame-based MR-guided laser ablation in an infant.

Hypothalamic hamartomata (HH) not only are usually associated with drug-resistant epilepsy but can also cause precocious puberty and developmental delay. Gelastic seizures are the most common type of seizures. Magnetic resonance image (MRI)-guided laser interstitial thermal therapy (LiTT) is a technique whereby a laser fibre is stereotactically implanted into a target lesion and heat is used to ablate whilst tissue temperature is monitored using MRI thermography. MRI-guided LiTT has proven to be an effective and safe method to treat HH. To use the LiTT system, highly accurate stereotactic fibre implantation is required. This can be achieved by the use of frame-based or frameless neuronavigation techniques. However, these techniques generally involve rigid head immobilisation using cranial pin fixation. Patients need sufficient skull thickness to safely secure the pins and sufficient skull rigidity to prevent deformation. Hence, most of the clinical reports on the use of LiTT for children describe patients aged 2 years or older. We report a novel and practical technique of using a paste cast helmet to securely place a stereotactic frame in a 5-month-old infant with HH and drug-resistant epilepsy that allowed the successful application of MRI-guided LiTT.

Guided Self-help Teletherapy for Behavioural Difficulties in Children with Epilepsy.

Behavioural difficulties impact greatly upon quality of life for children with chronic illness and their families but are often not identified or adequately treated, possibly due to the separation of physical and mental health services. This case study describes the content and outcomes of guided self-help teletherapy for behavioural difficulties in a child with epilepsy and complex needs using an evidence-based behavioural parenting protocol delivered within a paediatric hospital setting. Behavioural difficulties and progress towards the family's self-identified goals were monitored at each session. Validated measures of mental health and quality of life in children were completed before and after intervention and satisfaction was measured at the end of treatment. Measures demonstrated clear progress towards the family's goals and reduction in weekly ratings of behavioural difficulties. This case demonstrates that a guided self-help teletherapy approach delivered from within the paediatric setting may be one way of meeting unmet need.

Diagnostic algorithm for children presenting with epilepsia partialis continua.

OBJECTIVE: To characterize a cohort of children with epilepsia partialis continua (EPC) and develop a diagnostic algorithm incorporating key differential diagnoses. METHODS: Children presenting with EPC to a tertiary pediatric neurology center between 2002 and 2019 were characterized. RESULTS: Fifty-four children fulfilled EPC criteria. Median age at onset was 7 years (range 0.6-15), with median follow-up of 4.3 years (range 0.2-16). The diagnosis was Rasmussen encephalitis (RE) in 30 of 54 (56%), a mitochondrial disorder in 12 of 54 (22.2%), and magnetic resonance imaging (MRI) lesion-positive focal epilepsy in 6 of 54 (11.1%). No diagnosis was made in 5 of 54 (9%). Children with mitochondrial disorders developed EPC earlier; each additional year at presentation reduced the odds of a mitochondrial diagnosis by 26% (P = .02). Preceding developmental concerns (odds ratio [OR] 22, P < .001), no seizures prior to EPC (OR 22, P < .001), bilateral slowing on electroencephalogram (EEG) (OR 26, P < .001), and increased cerebrospinal fluid (CSF) protein level (OR 16) predicted a mitochondrial disorder. Asymmetry or hemiatrophy was evident on MRI at presentation with EPC in 18 of 30 (60%) children with RE, and in the remainder at a median of 6 months (range 3-15) after EPC onset. The first diagnostic test is brain MRI. Hemiatrophy may permit a diagnosis of RE with unilateral clinical and EEG findings. For children in whom a diagnosis of RE cannot be made on first scan but the clinical and radiological presentation resembles RE, repeat imaging every 6 months is recommended to detect progressive unicortical hemiatrophy, and brain biopsy should be considered. Evidence of intrathecal inflammation (oligoclonal bands and raised neopterin) can be supportive. In children with bihemispheric EPC, rapid polymerase gamma testing is recommended and if negative, sequencing mtDNA and whole-exome sequencing on blood-derived DNA should be performed. SIGNIFICANCE: Children presenting with EPC due to a mitochondrial disorder show clinical features distinguishing them from RE and structural epilepsies. A diagnostic algorithm for children with EPC will allow targeted investigation and timely diagnosis.

Focal epilepsy in SCN1A-mutation carrying patients: is there a role for epilepsy surgery?

Variants in the gene SCN1A are a common genetic cause for a wide range of epilepsy phenotypes ranging from febrile seizures to Dravet syndrome. Focal onset seizures and structural lesions can be present in these patients and the question arises whether epilepsy surgery should be considered. We report eight patients (mean age 13y 11mo [SD 8y 1mo], range 3-26y; four females, four males) with SCN1A variants, who underwent epilepsy surgery. Outcomes were variable and seemed to be directly related to the patient's anatomo-electroclinical epilepsy phenotype. Patients with Dravet syndrome had unfavourable outcomes, whilst patients with focal epilepsy, proven to arise from a single structural lesion, had good results. We conclude that the value of epilepsy surgery in patients with an SCN1A variant rests on two issues: understanding whether the variant is pathogenic and the patient's anatomo-electroclinical phenotype. Careful evaluation of epilepsy phenotype integrated with understanding the significance of genetic variants is essential in determining a patient's suitability for epilepsy surgery. Patients with focal onset epilepsy may benefit from epilepsy surgery, whereas those with Dravet syndrome do not. WHAT THIS PAPER ADDS: Patients should not automatically be excluded from epilepsy surgery evaluation if they carry an SCN1A variant. Patients with focal epilepsy may benefit from epilepsy surgery; those with Dravet syndrome do not.

Neuropsychiatric profile of paediatric hypothalamic hamartoma: systematic review and case series.

AIM: To evaluate neuropsychiatric comorbidities in children and adolescents with hypothalamic hamartoma. METHOD: We retrospectively analysed case notes for all individuals with hypothalamic hamartoma referred to Great Ormond Street Hospital, London, between 2000 and 2016. In addition, a systematic review aiming to identify all previous paediatric case series was performed. Psychiatric symptoms, demographics, physical comorbidities, and cognitive functioning were recorded for all cases where possible. Analyses were performed to determine which factors were associated with psychopathology and potential mechanisms investigated. RESULTS: Forty-six cases were included in the case series (28 males, 18 females; mean age at assessment 11y 8mo [1y 11mo-16y 11mo, SD 4y 0mo]). Twenty-nine papers representing data from 264 cases met inclusion criteria for the systematic review. Overall, at least 50% of cases presented with psychopathology. Epilepsy, intellectual disability, and male sex were associated with externalizing disorders (attention-deficit/hyperactivity disorder, conduct and oppositional defiance disorders, and rage attacks). Intellectual disability mediated the effects of epilepsy on externalizing psychopathology. No factors were associated with internalizing disorders (anxiety and depressive disorders), although these were not well reported. INTERPRETATION: Psychiatric comorbidities are highly prevalent in the presentation of paediatric hypothalamic hamartoma. The aetiology of psychopathology comprises a range of interacting biological and psychosocial factors with particular influence from epilepsy. Further research is required to achieve an evidence base for treatment. WHAT THIS PAPER ADDS: Over half of children with hypothalamic hamartoma present with psychiatric comorbidity. Externalizing and internalizing disorders are present in approximately 60% and 30% of children with hypothalamic hamartomas respectively. Epilepsy and male sex are associated with externalizing psychopathology. Intellectual disability mediates the association between epilepsy and externalizing symptoms. No clear associations are evident for internalizing disorders or precocious puberty.

PERFIL NEUROPSIQUIÁTRICO DEL HAMARTOMA HIPOTALÁMICO EN PEDIATRÍA: REVISIÓN SISTEMÁTICA Y SERIE DE CASOS: OBJETIVO: Evaluar las comorbilidades neuropsiquiátricas en niños y adolescentes con hamartoma hipotalámico. MÉTODO: En este estudio analizamos retrospectivamente las notas de los casos de todos los individuos con hamartoma hipotalámicos referidos al Great Ormond Street Hospital, London, entre el 2000 y 2016. Además, realizamos una revisión bibliográfica sistemática dirigida a identificar la serie de casos pediátricos. Síntomas psiquiátricos, demográfico, comorbilidades físicas y funcionamiento cognitivo fueron recolectados en todos los casos posibles.Se efectuaron análisis para determinar qué factores se asociaron con psicopatología y se investigaron mecanismos potenciales. RESULTADOS: En total 46 casos fueron incluidos en la serie de casos (28 masculinos, 18 femeninos, media de edad a la evaluación 11 años y 8 meses, DS 4 años y 0 mes). La revisión bibliográfica identifico 29 artículos describiendo 264 casos que reunieron criterios de inclusión para la extracción de datos. En total, al menos 50% de casos presentaban psicopatología. Epilepsia, discapacidad intelectual, y sexo masculino fueron asociados con desórdenes externos (déficit de atención con hiperactividad, desórdenes conductuales y oposicional desafiante, ataques de furia). Ningún factor fue asociado con la internalización de desórdenes neuropsiquiátricos (desórdenes de ansiedad y depresión), aunque éstos no fueron bien reportados. INTERPRETACIÓN: Las comorbilidades psiquiátricas son altamente prevalentes en la presentación del hamartoma hipotalámico pediátrico. La etiología de la psicopatología comprende un rango de interacciones biológicas y factores psicosociales con particular influencia de la epilepsia. Se requiere más información de investigación para reunir evidencia científica que guie el tratamiento.

PERFIL NEUROPSIQUIÁTRICO DO HAMARTOMA HIPOTALÂMICO PEDIÁTRICO: REVISÃO SISTEMÁTICA E SÉRIE DE CASOS: OBJETIVO: Avaliar comorbidades neuropsiquiátricas em crianças e adolescentes com hamartoma hipotalâmico. MÉTODO: Nós analisamos retrospectivamente os registros de casos de todos os indivíduos encaminhados para o Hospital Great Ormond Street, Londres, entre 2000 e 2016. Além disso, uma revisão sistemática visando identificar todos os casos pediátricos prévios foi realizada. Sintomas psiquiátricos, dados demográficos, comorbidades físicas, e funcionamento cognitivo foram registrados para todos os casos em que foi possível. Análises foram realizadas para determinar quais fatores se associavam com psicopatologia e potenciais mecanismos foram investigados. RESULTADOS: Quarenta e seis casos foram incluídos na série de casos (28 do sexo masculino, 18 do sexo feminino; média de idade na avaliação 11a 8m (1a 11m-16a 11m, DP 4a 0m). Vinte e nove artigos representando dados de 264 casos atenderam aos critérios de inclusão para a revisão sistemática. No total, pelo menos 50% dos casos apresentaram psicopatologia. Epilepsia, deficiência intelectual, e sexo masculino eram associados com desordens externalizantes (transtorno de déficit de atenção e hiperatividade, transtornos de conduta e de desafio oposicional, e ataques de raiva). A deficiência intelectual mediou os efeitos da epilepsia e da psicopatologia externalizante. Nenhum fator foi associado com transtornos internalizantes (ansiedade e transtornos depressivos), embora estes não tenham sido bem reportados. INTERPRETAÇÃO: Comorbidades psiquiátricas são altamente prevalentes na apresentação do hamartoma hipotalâmico pediátrico. A etiologia da psicopatologia envolve uma variedade de fatores biológicos e psicossociais que interagem, com particular influência da epilepsia. Mais pesquisas são necessárias para se atingir uma base de evidências para o tratamento.

Pre- and postsurgical cognitive trajectories and quantitative MRI changes in Rasmussen syndrome.

OBJECTIVE: To quantify the longitudinal cognitive trajectory, before and after surgery, of Rasmussen syndrome (RS), a rare disease characterized by focal epilepsy and progressive atrophy of one cerebral hemisphere. METHOD: Thirty-two patients (mean age = 6.7 years; 17 male, 16 left hemispheres affected) were identified from hospital records. The changes in intelligence scores during 2 important phases in the patients' journey to treatment were investigated: (1) during the preoperative period (n = 28, mean follow-up 3.4 years) and (2) from before to after surgery (n = 21 patients, mean time to follow-up 1.5 years). A volumetric magnetic resonance imaging (MRI) analysis of longitudinal changes in gray matter volume was conducted in a subsample of 18 patients. RESULTS: (1) IQ during the preoperative period: At baseline assessment (on average 2.4 years after seizure onset), the left RS group had lower verbal than nonverbal intellectual abilities, whereas the right group exhibited more difficulties in nonverbal than verbal intellect. Verbal and nonverbal scores declined during the follow-up in both groups, irrespective of the affected side. Hemispheric gray matter volumes declined over time in both groups in affected as well as unaffected hemispheres. (2) Postoperative IQ change: The left surgery group declined further in verbal and nonverbal intellect. The right group's nonverbal intellect declined after surgery, whereas verbal abilities did not. Patients with higher abilities preoperatively experienced large declines, whereas those with poorer abilities showed little change. Postoperative seizures negatively impacted on cognitive abilities. SIGNIFICANCE: During the chronic phase of the disease, parallel decline of verbal and nonverbal abilities suggest progressive bilateral hemispheric involvement, supported by evidence from MRI morphometry. Postsurgical cognitive losses are predicted by greater presurgical ability and continuing seizures. A shorter duration from seizure onset to surgery could reduce the postoperative cognitive burden by minimizing the decline in functions supported by the unaffected hemisphere.

Seizure and cognitive outcomes after resection of glioneuronal tumors in children.

OBJECTIVE: Glioneuronal tumors (GNTs) are well-recognized causes of chronic drug-resistant focal epilepsy in children. Our practice involves an initial period of radiological surveillance and antiepileptic medications, with surgery being reserved for those with radiological progression or refractory seizures. We planned to analyze the group of patients with low-grade GNTs, aiming to identify factors affecting seizure and cognitive outcomes. METHODS: We retrospectively reviewed the medical records of 150 children presenting to Great Ormond Street Hospital with seizures secondary to GNTs. Analysis of clinical, neuroimaging, neuropsychological, and surgical factors was performed to determine predictors of outcome. Seizure outcome at final follow-up was classified as either seizure-free (group A) or not seizure-free (group B) for patients with at least 12-months follow-up postsurgery. Full-scale intelligence quotient (FSIQ) was used as a measure of cognitive outcome. RESULTS: Eighty-six males and 64 females were identified. Median presurgical FSIQ was 81. One hundred twenty-one patients (80.5%) underwent surgery. Median follow-up after surgery was 2 years, with 92 patients (76%) having at least 12 months of follow-up after surgery. Seventy-four patients (80%) were seizure-free, and 18 (20%) continued to have seizures. Radiologically demonstrated complete tumor resection was associated with higher rates of seizure freedom (P = .026). Higher presurgical FSIQ was related to shorter epilepsy duration until surgery (P = .012) and to older age at seizure onset (P = .043). SIGNIFICANCE: A high proportion of children who present with epilepsy and GNTs go on to have surgical tumor resection with excellent postoperative seizure control. Complete resection is associated with a higher chance of seizure freedom. Higher presurgical cognitive functioning is associated with shorter duration of epilepsy prior to surgery and with older age at seizure onset. Given the high rate of eventual surgery, early surgical intervention should be considered in children with continuing seizures associated with GNTs.

Advantages and pitfalls of an extended gene panel for investigating complex neurometabolic phenotypes.

Neurometabolic disorders are markedly heterogeneous, both clinically and genetically, and are characterized by variable neurological dysfunction accompanied by suggestive neuroimaging or biochemical abnormalities. Despite early specialist input, delays in diagnosis and appropriate treatment initiation are common. Next-generation sequencing approaches still have limitations but are already enabling earlier and more efficient diagnoses in these patients. We designed a gene panel targeting 614 genes causing inborn errors of metabolism and tested its diagnostic efficacy in a paediatric cohort of 30 undiagnosed patients presenting with variable neurometabolic phenotypes. Genetic defects that could, at least partially, explain observed phenotypes were identified in 53% of cases. Where biochemical abnormalities pointing towards a particular gene defect were present, our panel identified diagnoses in 89% of patients. Phenotypes attributable to defects in more than one gene were seen in 13% of cases. The ability of in silico tools, including structure-guided prediction programmes to characterize novel missense variants were also interrogated. Our study expands the genetic, clinical and biochemical phenotypes of well-characterized (POMGNT1, TPP1) and recently identified disorders (PGAP2, ACSF3, SERAC1, AFG3L2, DPYS). Overall, our panel was accurate and efficient, demonstrating good potential for applying similar approaches to clinically and biochemically diverse neurometabolic disease cohorts.

Rasmussen Syndrome and Other Inflammatory Epilepsies.

An underlying immune basis is emerging in an increasing number of epileptic and encephalopathic syndromes. The immunopathological mechanisms may be categorized into antibody-mediated, T-cell cytotoxicity, and microglia-induced degeneration. The immune basis in Rasmussen syndrome is thought to be T-cell mediated. Antibodies to extracellular and intracellular epitopes are implicated in limbic and other encephalitides, characterized by seizures, movement disorder, sleep disorder, obtundation, psychosis, mutism, and other psychiatric symptoms. Extracellular antibodies are directed at cell-surface-expressed neuronal or glial proteins: glutamate receptors (N-methyl-D-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazol-propionic acid), voltage-gated potassium channel complex (contactin-associated-protein 2 [CASPR2], contactin-2 and leucin-rich, glioma-inactivated 1 [LGI1]), and γ-aminobutyric acid (GABA) receptors (GABABR and GABAAR). Antibodies to intracellular antigens are less commonly seen (for example, glutamic acid decarboxylase). Diseases caused by antibodies to cell-surface-expressed antigens are better expected to respond to immune treatments than to those where the presumed mechanism is T-cell driven. Antibodies to the folate receptor FR1 are a cause of primary cerebral folate deficiency. Febrile infection-related epilepsy syndrome (FIRES) may also have an immune basis, although this is yet to be proven. For all these epilepsies, the best treatment and the long-term outcomes are not yet clear.

Epilepsy due to PNPO mutations: genotype, environment and treatment affect presentation and outcome.

The first described patients with pyridox(am)ine 5'-phosphate oxidase deficiency all had neonatal onset seizures that did not respond to treatment with pyridoxine but responded to treatment with pyridoxal 5'-phosphate. Our data suggest, however, that the clinical spectrum of pyridox(am)ine 5'-phosphate oxidase deficiency is much broader than has been reported in the literature. Sequencing of the PNPO gene was undertaken for a cohort of 82 individuals who had shown a reduction in frequency and severity of seizures in response to pyridoxine or pyridoxal 5'-phosphate. Novel sequence changes were studied using a new cell-free expression system and a mass spectrometry-based assay for pyridoxamine phosphate oxidase. Three groups of patients with PNPO mutations that had reduced enzyme activity were identified: (i) patients with neonatal onset seizures responding to pyridoxal 5'-phosphate (n = 6); (ii) a patient with infantile spasms (onset 5 months) responsive to pyridoxal 5'-phosphate (n = 1); and (iii) patients with seizures starting under 3 months of age responding to pyridoxine (n = 8). Data suggest that certain genotypes (R225H/C and D33V) are more likely to result in seizures that to respond to treatment with pyridoxine. Other mutations seem to be associated with infertility, miscarriage and prematurity. However, the situation is clearly complex with the same combination of mutations being seen in patients who responded and did not respond to pyridoxine. It is possible that pyridoxine responsiveness in PNPO deficiency is affected by prematurity and age at the time of the therapeutic trial. Other additional factors that are likely to influence treatment response and outcome include riboflavin status and how well the foetus has been supplied with vitamin B6 by the mother. For some patients there was a worsening of symptoms on changing from pyridoxine to pyridoxal 5'-phosphate. Many of the mutations in PNPO affected residues involved in binding flavin mononucleotide or pyridoxal 5'-phosphate and many of them showed residual enzyme activity. One sequence change (R116Q), predicted to affect flavin mononucleotide binding and binding of the two PNPO dimers, and with high residual activity was found in Groups (ii) and (iii). This sequence change has been reported in the 1000 Genomes project suggesting it could be a polymorphism but alternatively it could be a common mutation, perhaps responsible for the susceptibility locus for genetic generalized epilepsy on 17q21.32 (close to rs72823592). We believe the reduction in PNPO activity and B6-responsive epilepsy in the patients reported here indicates that it contributes to the pathogenesis of epilepsy.

Vagus nerve stimulation for drug-resistant epilepsy: a European long-term study up to 24 months in 347 children.

OBJECTIVE: To gain insight into the long-term impact of vagus nerve stimulation (with VNS Therapy) in children with drug-resistant epilepsy, we conducted the largest retrospective multicenter study to date over an extended follow-up period of up to 24 months. METHODS: The primary objective was to assess change in seizure frequency of the predominant seizure type (defined as the most disabling seizure) following VNS device implantation. Treating physicians collected data from patient records from baseline to 6, 12, and 24 months of follow-up. RESULTS: The analysis population included 347 children (aged 6 months to 17.9 years at the time of implant). At 6, 12, and 24 months after implantation, 32.5%, 37.6%, and 43.8%, respectively, of patients had ≥ 50% reduction in baseline seizure frequency of the predominant seizure type. The responder rate was higher in a subgroup of patients who had no change in antiepileptic drugs (AEDs) during the study. Favorable results were also evident for all secondary outcome measures including changes in seizure duration, ictal severity, postictal severity, quality of life, clinical global impression of improvement, and safety. Post hoc analyses demonstrated a statistically significant correlation between VNS total charge delivered per day and an increase in response rate. VNS Therapy is indicated as adjunctive therapy in children with focal, structural epilepsies, who for any reason are not good candidates for surgical treatment following the trial of two or more AEDs. Children with predominantly generalized seizures from genetic, structural epilepsies, like Dravet syndrome or Lennox-Gastaut syndrome, could also benefit from VNS Therapy. SIGNIFICANCE: The results demonstrate that adjunctive VNS Therapy in children with drug-resistant epilepsy reduces seizure frequency and is well tolerated over a 2-year follow-up period. No new safety issues were identified. A post hoc analysis revealed a dose-response correlation for VNS in patients with epilepsy.

COL4A1 mutations should not be a contraindication for epilepsy surgery.

PURPOSE: We describe the first case in the literature of complication-free epilepsy surgery in a paediatric patient with collagen type IV alpha 1 (COL4A1) mutation. METHODS: This is a case report. RESULTS: COL4A1 mutations disrupt the integrity of vascular basement membranes, so predisposing to a broad spectrum of disorders including periventricular leucomalacia, haemorrhagic stroke, aneurysm formation, epilepsy and developmental delay. Intracranial haemorrhage is reported and may be recurrent or associated with trauma and anticoagulant therapy. Children have an increased risk of stroke with general anaesthesia. A 6-year-old girl, COL4A1 mutation positive, had drug-resistant epilepsy, cerebral palsy and developmental delay. Following presurgical evaluation, she was a candidate for corpus callosotomy. Previous general anaesthesia had been uncomplicated. Preoperative full blood count and coagulation studies were normal. Perioperatively, normotension was maintained, and anticoagulation was avoided. A complete corpus callosotomy was performed with no intracranial haemorrhage or other perioperative complications. CONCLUSION: Although there is an increased risk of intracranial haemorrhages in COL4A1 patients, this is not clearly quantifiable. There are minimal data in the literature on the subject. COL4A1 mutations should not be a contraindication for presurgical evaluation. Each patient should be individually evaluated and assessed, risks and benefits were carefully weighed, and informed decisions were reached after thorough discussions with patients and families.

Antibodies to surface dopamine-2 receptor in autoimmune movement and psychiatric disorders.

Recent reports of autoantibodies that bind to neuronal surface receptors or synaptic proteins have defined treatable forms of autoimmune encephalitis. Despite these developments, many cases of encephalitis remain unexplained. We have previously described a basal ganglia encephalitis with dominant movement and psychiatric disease, and proposed an autoimmune aetiology. Given the role of dopamine and dopamine receptors in the control of movement and behaviour, we hypothesized that patients with basal ganglia encephalitis and other putative autoimmune basal ganglia disorders harboured serum autoantibodies against important dopamine surface proteins. Basal ganglia encephalitis sera immunolabelled live surface cultured neurons that have high expression of dopamine surface proteins. To detect autoantibodies, we performed flow cytometry cell-based assays using human embryonic kidney cells to express surface antigens. Twelve of 17 children (aged 0.4-15 years, nine males) with basal ganglia encephalitis had elevated immunoglobulin G to extracellular dopamine-2 receptor, compared with 0/67 controls. Immunofluorescence on wild-type mouse brain showed that basal ganglia encephalitis sera immunolabelled microtubule-associated protein 2-positive neurons in striatum and also in cultured striatal neurons, whereas the immunolabelling was significantly decreased in dopamine-2 receptor knock-out brains. Immunocytochemistry confirmed that immunoreactivity localized to the surface of dopamine-2 receptor-transfected cells. Immunoabsorption of basal ganglia encephalitis sera on dopamine-2 receptor-transfected human embryonic kidney cells decreased immunolabelling of dopamine-2 receptor-transfected human embryonic kidney cells, neurons and wild-type mouse brain. Using a similar flow cytometry cell-based assay, we found no elevated immunoglobulin G binding to dopamine 1, 3 or 5 receptor, dopamine transporter or N-methyl-d-aspartate receptor. The 12 dopamine-2 receptor antibody-positive patients with encephalitis had movement disorders characterized by parkinsonism, dystonia and chorea. In addition, the patients had psychiatric disturbance with emotional lability, attention deficit and psychosis. Brain magnetic resonance imaging showed lesions localized to the basal ganglia in 50% of the patients. Elevated dopamine-2 receptor immunoglobulin G was also found in 10/30 patients with Sydenham's chorea, 0/22 patients with paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection and 4/44 patients with Tourette's syndrome. No dopamine-1 receptor immunoglobulin G was detected in any disease or control groups. We conclude that assessment of dopamine-2 receptor antibodies can help define autoimmune movement and psychiatric disorders.

Inborn errors of metabolism causing epilepsy.

Seizures may be the first and the major presenting feature of an inborn error of metabolism (IEM), for example in a neonate with pyridoxine-dependent epilepsy. In other IEMs, seizures may be preceded by other major symptoms: by a reduced level of consciousness in a child with an organic acidaemia or urea cycle defect; or by loss of skills, progressive weakness, ataxia, and upper motor signs in a child with a lysosomal storage disorder or peroxisomal leukodystrophy. This review concentrates on those IEMs for which specific treatment is available. The common metabolic causes of seizures vary according to the age at presentation. Features from the history, examination, imaging, and first line biochemical investigations can all provide clues to an inborn error. This review attempts to delineate these and to provide a guide to the specific tests that can be used to make the diagnosis of disorders with specific treatment.

Accuracy of robot-assisted stereotactic MRI-guided laser ablation in children with epilepsy.

OBJECTIVE: Robot-assisted (RA) stereotactic MRI-guided laser ablation has been reported to be a safe and effective technique for the treatment of epileptogenic foci in children and adults. In this study the authors aimed to assess the accuracy of RA stereotactic MRI-guided laser fiber placement in children and to identify factors that might increase the risk of misplacement. METHODS: A retrospective single-institution review of all children from 2019 to 2022 who underwent RA stereotactic MRI-guided laser ablation for epilepsy was undertaken. Placement error was calculated at the target by measuring the Euclidean distance between the implanted laser fiber position and the preoperatively planned position. Collected data included age at surgery, sex, pathology, date of robot calibration, number of catheters, entry position, entry angle, extracranial soft-tissue thickness, bone thickness, and intracranial catheter length. A systematic review of the literature was also performed using Ovid Medline, Ovid Embase, and the Cochrane Central Register of Controlled Trials. RESULTS: In 28 children with epilepsy, the authors assessed 35 RA stereotactic MRI-guided laser ablation fiber placements. Twenty (71.4%) children had undergone ablation for hypothalamic hamartoma, 7 children (25.0%) for presumed insular focal cortical dysplasia, and 1 patient (3.6%) for periventricular nodular heterotopia. Nineteen children were male (67.9.%) and 9 were female (32.1%). The median age at the time of the procedure was 7.67 years (IQR 4.58-12.26 years). The median target point localization error (TPLE) was 1.27 mm (IQR 0.76-1.71 mm). The median offset error between the planned and actual trajectories was 1.04° (IQR 0.73°-1.46°). Patient age, sex, pathology and the time interval between date of surgery and robot calibration, entry position, entry angle, soft-tissue thickness, bone thickness, and intracranial length were not associated with the placement accuracy of the implanted laser fibers. However, the number of catheters placed did correlate with the offset angle error on univariate analysis (ρ = 0.387, p = 0.022). There were no immediate surgical complications. Meta-analysis indicated that the overall pooled mean TPLE was 1.46 mm (95% CI -0.58 to 3.49 mm). CONCLUSIONS: RA stereotactic MRI-guided laser ablation for epilepsy in children is highly accurate. These data will aid surgical planning.

Intraoperative MRI Assessment of the Tissue Damage during Laser Ablation of Hypothalamic Hamartoma.

Laser ablation for treatment of hypothalamic hamartoma (HH) is a minimally invasive and effective technique used to destroy hamartomatous tissue and disconnect it from the functioning brain. Currently, the gold standard to evaluate the amount of tissue being "burned" is the use of heat maps during the ablation procedure. However, these maps have low spatial resolution and can be misleading in terms of extension of the tissue damage. The aim of this study is to use different MRI sequences immediately after each laser ablation and correlate the extension of signal changes with the volume of malacic changes in a long-term follow-up scan. During the laser ablation procedure, we imaged the hypothalamic region with high-resolution axial diffusion-weighted images (DWI) and T2-weighted images (T2WI) after each ablation. At the end of the procedure, we also added a post-contrast T1-weighted image (T1WI) of the same region. We then correlated the product of the maximum diameters on axial showing signal changes (acute oedema on T2WI, DWI restriction rim, DWI hypointense core and post-contrast T1WI rim) with the product of the maximum diameters on axial T2WI of the malacic changes in the follow-up scan, both as a fraction of the total area of the hamartoma. The area of the hypointense core on DWI acquired immediately after the laser ablation statistically correlated better with the final area of encephalomalacia, while the T2WI, hyperintense oedema, DWI rim and T1WI rim of enhancement tended to overestimate the encephalomalacic damage. In conclusion, the use of intraoperative sequences (in particular DWI) during laser ablation can give surgeons valuable information in real time about the effective heating damage on the hamartomatous tissue, with better spatial resolution in comparison to the thermal maps.