Predictors of outcomes after surgery for medically intractable insular epilepsy: A systematic review and individual participant data meta-analysis.

Insular epilepsy (IE) is an increasingly recognized cause of drug-resistant epilepsy amenable to surgery. However, concerns of suboptimal seizure control and permanent neurological morbidity hamper widespread adoption of surgery for IE. We performed a systematic review and individual participant data meta-analysis to determine the efficacy and safety profile of surgery for IE and identify predictors of outcomes.

Hypothalamic hamartoma associated with polymicrogyria and periventricular nodular heterotopia in children: report of three cases and discussion of the origin of the seizures.

Purpose: Hypothalamic hamartomas (HH) are malformations responsible for drug-resistant epilepsy. HH are usually isolated or part of a genetic syndrome, such as Pallister-Hall. Exceptionally they can be associated with other brain malformations such as polymicrogyria (PMG) and periventricular nodular heterotopia (PNH).

Complete callosotomy in children with drop attacks; A retrospective monocentric study of 50 patients.

Purpose: Corpus callosotomy is a palliative surgical procedure for patients with drug-resistant epilepsy and suffering from drop attacks, which are a source of major deterioration in quality of life and can be responsible for severe traumatic injury. The objective of this study is to identify clinical markers that would predict a better outcome in terms of drop attacks and other types of epileptic seizures.

Methods: We reviewed a retrospective series of children who underwent complete corpus callosotomy at our institution, between January 1998 and February 2019.

Hippocampal sclerosis and epilepsy surgery in neurofibromatosis type 1: case report of a 3-year-old child explored by SEEG and review of the literature.

Purpose: Epilepsy associated with neurofibromatosis type 1 (NF1) is infrequent and usually controlled with anti-epileptic drugs. However, in some drug-resistant patients a presurgical evaluation should be considered. Hippocampal sclerosis (HS) is one of the rare causes of epilepsy in neurofibromatosis type 1, which can lead to surgery.

Clinical semiology of temporal lobe seizures in preschool children: contribution of invasive recording to anatomical classification.

Focal seizure semiology is often inadequately studied, specifically in preschool children. Among drug-resistant epilepsies amenable to surgery, temporal lobe seizure semiology has been widely described in this age group. Nevertheless, a systematic anatomo-electroclinical study has never been performed.

F-FDG-PET hypometabolic pattern reveals multifocal epileptic foci despite limited unique stereotyped seizures.

Purpose: Interictal positron emission tomography (PET) with F-FDG has largely proved its utility in presurgical evaluation of drug-resistant epilepsies (DRE) and in the surgical outcomes. Interictal hypometabolism topography is related to the neuronal networks involved in the seizure onset zone (SOZ) and spread pathways. F-FDG PET has a good prognostic value for post-surgical outcome, especially in cases with unique focal ictal semiology and a limited extent of hypometabolism.

Focal polymicrogyria in children: Contribution of invasive explorations and epileptogenicity mapping in the surgical decision.

Objective: Report of the contribution of invasive EEG (iEEG) and epileptogenicity mappings (EM) in a pediatric cohort of patients with epilepsy associated with focal polymicrogyria (PMG) and candidates for resective surgery.

Method: Retrospective pediatric case series of patients presenting focal PMG-related refractory epilepsy undergoing an invasive exploration (iEEG) at Fondation Rothschild Hospital. We reviewed clinical data, structural MRI, and visual analysis of iEEG recordings.

Management and results of epilepsy surgery associated with acyclovir prophylaxis in four pediatric patients with drug-resistant epilepsy due to herpetic encephalitis and review of the literature.

Purpose: Herpes simplex virus encephalitis (HSE) is the most common cause of sporadic viral encephalitis in children and is responsible for epilepsy in approximately half of patients. In addition to medical treatment, epilepsy surgery may be offered to drug-resistant patients but carries a high risk of relapse of herpetic encephalitis. We are reporting our series of patients operated on between 2000 and 2019 with the systematic administration of acyclovir (ACV).

Surgical treatment of hypothalamic hamartomas.

Hypothalamic hamartomas are aberrant masses, composed of abnormally distributed neurons and glia. Along endocrine and cognitive symptoms, they may cause epileptic seizures, including the specific gelastic and dacrystic seizures. Surgery is the treatment of drug-resistant hamartoma epilepsy, with associated positive results on endocrine, psychiatric, and cognitive symptoms.

Identification of TSC1 or TSC2 mutation limited to the tumor in three cases of solitary subependymal giant cell astrocytoma using next-generation sequencing technology.

Purpose: Subependymal giant-cell astrocytomas (SEGAs) are low grade intraventricular tumors typically found in patients with tuberous sclerosis complex (TSC). The occurrence of SEGA in non TSC patients is very rare and from a genetic point of view these so-called solitary SEGA are thought to result either from somatic mutations in one of the TSC genes (TSC1 or TSC2) limited to the tumor, or be part of a "forme fruste" of TSC with somatic mosaicism. We report on three new cases of solitary SEGA with germline and somatic mutation analysis.

Seizure outcome and prognostic factors for surgical management of hypothalamic hamartomas in children.

Purpose: Hypothalamic hamartomas (HH) are rare benign lesions frequently associated with gelastic seizures early in life. Epilepsy can progress to multiple seizure types with cognitive impairment and behavioural disturbance, leading in some cases to epileptic encephalopathy.

Methods: We reviewed a retrospective series of 112 children treated in a single center, between 1998 and 2017.

Dissecting the genetic basis of focal cortical dysplasia: a large cohort study.

Genetic malformations of cortical development (MCDs), such as mild MCDs (mMCD), focal cortical dysplasia (FCD), and hemimegalencephaly (HME), are major causes of severe pediatric refractory epilepsies subjected to neurosurgery. FCD2 are characterized by neuropathological hallmarks that include enlarged dysmorphic neurons (DNs) and balloon cells (BCs). Here, we provide a comprehensive assessment of the contribution of germline and somatic variants in a large cohort of surgical MCD cases.

Parasagittal hemispherotomy in hemispheric polymicrogyria with electrical status epilepticus during slow sleep: Indications, results and follow-up.

Purpose: Polymicrogyria (PMG), although the most common brain malformation, represents a low percentage among patients operated on for epilepsy. In cases of hemispheric PMG, electrical status epilepticus during slow sleep (ESESS) may occur leading to an aggravation of the neurological condition and a risk of drug resistance. In such cases, surgical treatment can be offered.

Optimizing the Detection of Subtle Insular Lesions on MRI When Insular Epilepsy Is Suspected.

Insular epilepsy is underdiagnosed and accounts for a number of failed operations. Identifying insular target lesions on MR imaging can help guide intracranial electroencephalography and improve the outcome of surgery. In this study, we present a novel method of exploring the insular region for subtle lesions on 3D MR imaging by MPR postprocessing of slices in oblique reference planes.

SEEG-guided radiofrequency thermocoagulation of epileptic foci in the paediatric population: Feasibility, safety and efficacy.

Purpose: Focal epilepsy in children may be refractory to pharmacological treatment and surgical resection may be an appropriate option. When invasive electroencephalogram is required in the presurgical evaluation, depth electrodes can be used to create focal lesions in the epileptogenic zone using radiofrequency thermocoagulation (RFTC), to disrupt the epileptogenic zone.

Methods: This study aimed to assess the efficacy and safety of RFTC in a paediatric population of 46 patients.

Invasive evaluation in children (SEEG vs subdural grids).

Designed from the 60s to the 80s for adults, and despite the development of many new techniques, invasive explorations still have indications in children with focal drug-resistant epilepsy. The main types are stereoelectroencephalography (SEEG) and subdural explorations (SDE). They provide precise information on the localization of the epileptogenic zone (EZ), its relationships with eloquent cortex, and the feasibility of performing a tailored surgical resection.

Investigation of paediatric occipital epilepsy using stereo-EEG reveals a better surgical outcome than in adults, especially when the supracalcarine area is affected.

Occipital epilepsy is the least common among surgical series because: (1) the location makes it hard to asses by EEG; (2) the seizure semiology often reflects propagation; and (3) surgery entails a high risk of neurological deficits. In children, subjective symptoms are harder to assess, adding to the difficulty of a proper diagnosis. We aimed to determine electroclinical characteristics of occipital lobe epilepsy in a paediatric population by reviewing 20 children between one and 16 years, who had undergone intracranial recordings with depth electrodes.

Refractory epilepsy in preschool children with tuberous sclerosis complex: Early surgical treatment and outcome.

Purpose: Epilepsy surgery has been shown to be effective in treating focal epilepsy related to tuberous sclerosis complex (TSC). We analyzed the advantage of early surgical management in terms of seizure frequency and development.

Method: We retrospectively studied the 15 patients younger than 6 years who underwent resective surgery between 2006 and 2016.

Surgery for subependymal giant cell astrocytomas in children with tuberous sclerosis complex.

Objective: Subependymal giant cell astrocytomas (SEGAs) are low-grade intraventricular glial tumors that develop in 10-15% of patients with tuberous sclerosis complex; they often cause hydrocephalus and are potentially accessible to a surgical treatment. Our aim is to evaluate morbidity and results after surgery in symptomatic and asymptomatic patients.

Method: We present a retrospective series of 18 pediatric patients operated on for SEGA between 2006 and 2016 at our institution.

Refractory spasms of focal onset-A potentially curable disease that should lead to rapid surgical evaluation.

Purpose: Infantile spasms (IS) can occur as the only seizure type in children with surgically amenable epilepsies. Although early surgery has shown positive effects, little is known regarding outcomes.

Methods: We retrospectively reviewed all children with IS referred to our tertiary center between 2002 and 2014 and try to define factors of outcome.

Involvement of GATOR complex genes in familial focal epilepsies and focal cortical dysplasia.

Objective: The discovery of mutations in DEPDC5 in familial focal epilepsies has introduced a novel pathomechanism to a field so far dominated by ion channelopathies. DEPDC5 is part of a complex named GAP activity toward RAGs (GATOR) complex 1 (GATOR1), together with the proteins NPRL2 and NPRL3, and acts to inhibit the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) pathway. GATOR1 is in turn inhibited by the GATOR2 complex.

Stereo-electroencephalography (SEEG) in children surgically cured of their epilepsy.

Purpose: SEEG in children has a low morbidity and leads to a good surgical outcome, in particular in younger patients. We analysed, in detail, the SEEG data of patients that were subsequently cured by surgery.

Methods: We selected the 48 children explored between 2009 and 2013 in our centre and surgically cured after SEEG-based resections with at least one-year follow-up.