Temporal lobe epilepsy is a fairly homogenous syndrome in adults, with hippocampal sclerosis being the commonest etiology. In children, temporal lobe epilepsy is more commonly due to cortical dysplasia or tumors. The semiology and electrophysiology of temporal lobe seizures in children are distinct from adults and have age-dependent variations. The first-line treatment option in children includes antiepileptic drugs. Ketogenic diet and surgery are therapeutic options in refractory pediatric temporal lobe epilepsy.

The epilepsies are socially handicapping disorders and even a single seizure occurring in certain circumstances may have disastrous effect. The impact of epilepsy on every aspect of both the lives of the child and family is significant. Issues such as mental retardation, subtle neuropsychologic disturbances, cognitive problems, behavioral problems and learning difficulties are major factors affecting the children with epilepsy. Drug treatment is the major form of therapy for a vast majority of children with epilepsy. The choice of antiepileptic drugs (AEDs) in a child depends on the type of seizures, syndrome diagnosis, age of the patient and its consequent adverse effects. The metabolism of AED also differs according to the pediatric age group, requiring different dose regimens. Here, a brief review of AED used in the pediatric age group is presented.

Epilepsy and cognition have a multi-tiered reciprocal relationship. Alteration in cognitive abilities and performance may occur in tandem with persistent seizures in a patient with epilepsy. Age at onset, type of seizures, frequency of seizures, types of underlying epilepsy syndrome, and the underlying pathological brain substrate driving epilepsy may all have variable and independent effects on cognition. Therapeutic intervention with anti-epileptic drugs (AEDs) variably modulates cognitive abilities in a patient with epilepsy. Pathological substrate specific effects can compound the potential negative effects of AEDs on cognition. In this review all these aspects are addressed with an analysis of relevant evidence from peer-reviewed publications.

Children with intractable epilepsy are at considerable risk for cognitive impairment, school failure, behaviour and mental health problems and overall compromised quality of life. It influences the development of cognitive functions during the period of brain plasticity. Fifty percent of patients with intractable epilepsy have surgically remediable epilepsy syndromes. Epilepsy surgery can lead to seizure freedom following which development of functions in the residual brain occur which leads to cognitive improvement. Social aspects, side effects of antiepileptics, seizure perception and the overall level of quality of life are found to improve after surgery. The nature of the underlying brain disorder giving rise to the seizures appears to affect outcome. Follow up period is essential to determine effects of cognition after epilepsy surgery. It should be long enough for reconfiguration of the individual, family functioning and for restitution at the level of brain plasticity to occur.

Although definititions of refractory epilepsy vary, about 40% of prevalent cases of epilepsy are not controlled by anti-epileptic drugs. A substantial proportion of this population requires palliative therapy since only a minority are candidates for epilepsy surgery. Drug therapy can be optimised after accurate classification of the epilepsy. Monotherapy is often as effective as polytherapy with fewer adverse effects. Depression and CNS adverse effects significantly impact quality of life and must be systematically screened for and treated. The ketogenic diet and vagal nerve stimulation provide substantial seizure control in a significant number of cases and may be used synergistically. Deep brain stimulation is another promising modality.

Epilepsy is a significant and commonplace neurological disability in the pediatric population. Data from increasingly larger and more representative studies have brought about noteworthy changes in our understanding of the prognosis of epilepsy in the pediatric age-group. Prevalence rates for epilepsy in both the developing and the developed world are surprisingly similar despite distinct differences in incidence and large treatment gaps in the developing world; this strongly points towards the possibility of spontaneous remission, at least in some patients. Prognosis after an isolated first seizure is generally quite favorable, but worsens with recurring seizures, remote symptomatic etiology, and the presence of abnormalities on EEG. Presently available antiepileptic drugs (AEDs) are at best seizure suppressant in their action and have not been shown to be antiepileptic in the sense that they alter the long-term prognosis of the epilepsy for the better. Epilepsy syndromes can be considered to belong to distinct groups on the basis of their prognosis. Some have an excellent outcome in terms of seizure freedom and neurological development; yet others have a grim prognosis with respect to these variables. Factors that impact on the prognosis of treated epilepsy are being understood and include the specific etiology, age of onset of epilepsy, and EEG findings. Epileptics, especially those with remote symptomatic seizures and refractory epilepsy, suffer higher mortality as compared to the general population. While the outcomes in terms of seizure freedom in patients with epilepsy appear favorable, disturbing data on psychosocial morbidity are coming to light and are reflected in the lower rates of higher education, employment, marriage, and fertility among epileptics.

The various imaging techniques used in the diagnostic workup of the epileptic child are presented in this review, with special emphasis on magnetic resonance imaging (MRI) which has become the mainstay for the anatomical imaging workup. The MRI findings in various childhood epilepsies are discussed.

The underlying pathological substrates of localization-related epilepsy are varied. In children, the foremost among these are the malformative disorders of cortical development of which focal cortical dysplasia (FCD) is the most prominent. Other conditions include tuberous sclerosis, Sturge-Weber syndrome, vascular malformations, ischemic lesions and epilepsy-associated tumors. As in adults, medial temporal sclerosis is also a common histopathological finding. Resective surgery for extratemporal lesions is now the treatment of choice as more accurate identification of lesion with modern imaging and electrophysiological techniques is possible and a good surgical outcome is seen in most cases. This review describes the common causal histopathological substrates of epilepsy in children.

This review focuses on the present status of inter-ictal surface EEG, simultaneous ictal video-EEG and intracranial EEG in the evaluation of children for epilepsy surgery. This is considered in the context of high-end structural and functional neuroimaging available today. Initially the concept of the epileptogenic zone and its different components are discussed so that it is easier to understand how the EEG helps in localization. Methods of maximizing the yield of the EEG are emphasized. Abnormalities in the inter-ictal and ictal EEG are discussed in some detail. Special emphasis is given to the seizure semiology and how this helps in identifying which lobe is primarily involved. Limitations of surface EEG are then detailed, with special emphasis on young infants. Finally the discussion turns to intracranial EEG. This is used intra-operatively in one stage epilepsy surgery and more definitively extra-operatively in two stage surgery not only to define the epileptogenic zone but also to identify critical cortex.

The objective of the multimodality presurgical evaluation in patients with refractory epilepsy is to establish sufficient concordance among the various investigations. There should be maximum overlap in the epileptogenic zone, the irritative zone, the ictal onset zone, the functional deficit zone and the symptomatogenic zone. The ictal and interictal electroencephalogram measures the localization of epileptiform discharges, which should be concordant with structural abnormalities noted on MRI brain and functional abnormalities in the form of a zone of hypometabolism on fluorodeoxyglucose positron emission tomography, interictal single photon emission computerized tomography (SPECT) or hyperperfusion of the epileptogenic zone on ictal SPECT for a good surgical outcome. There should be no conflicting data from any of these studies, neuropsychological evaluation or seizure semiology.

Epilepsy surgery for the child is increasingly being offered as a management option even in infants, due to advances in neurosurgery and pediatric neuro-anesthesia, coupled with a better understanding of neurophysiological evaluation/monitoring. Anesthesia for children in the setting of a major surgery like epilepsy surgery presents a variety of challenges. This article deals with the physiology of electroencephalogram and the effects of anesthetic agents on neurophysiology, sedation and anesthesia for investigative procedures and definitive surgery with major blood loss and fluid shifts, with special emphasis on the small child and awake craniotomy in the older child.

Gelastic or laughter seizures have been poorly understood but are a classic seizure entity. Though rare, gelastic seizures have been described most often in association with hypothalamic hamartomas. No effective medical therapy is available to control these gelastic seizures and early individualized surgical management remains the mainstay. Current opinion on the pathophysiology, evaluation and current management of the poorly understood entity of gelastic seizures is reviewed along with various surgical procedures for hypothalamic hamartoma.

Objectives: To outline the indications, surgical anatomy, approaches and complications. Materials and Methods: We review the anatomy, surgical approaches and possible benefits over wider resections in the temporal lobe. We compare the damage to the temporal lobe by these approaches and review the complications. Conclusions: Selective amygdalohippocampectomy is an effective operation for mesial temporal lobe epilepsy due to mesial temporal sclerosis, particularly on the left side.

Children with lesion-related extratemporal epilepsies with suboptimal seizure control should be identified early and referred for presurgical evaluation before irreversible deterioration in cognitive or psychosocial functions ensues due to long-standing disabling seizures and chronic antiepileptic drug-related side effects. The success of epilepsy surgery depends upon the accurate preoperative localization of the epileptogenic zone and its complete resection. Children with medically refractory lesional epilepsies belong to different categories depending upon the degree of complexity involved in the presurgical evaluation to define their epileptogenic zone. While some patients, such as those with tumoral epilepsy syndrome, can be selected for surgery by simple noninvasive presurgical evaluation strategy, others with malformations of cortical development and those with multiple lesions often require complex and invasive means to define their epileptogenic zone. Recent advances in structural and functional imaging have obviated the need of invasive monitoring in the majority. These advances along with improvement in surgical techniques have made resective surgery safer and more effective. Prospective comprehensive follow-up studies are needed to evaluate the long-term seizure, cognitive, psychosocial, educational and occupational outcomes of surgically treated children with extratemporal epilepsies.

Objectives: To outline the evolution, indications, surgical techniques and complications of hemispheric procedures for intractable epilepsy. Materials and Methods: We review the patient selection, timing of surgery, surgical procedures and complications. Conclusions: There are clear indications for hemispheric procedures for intractable epilepsy, but the timing remains a concern in certain cases. The complications have reduced with the modified anatomical, functional and disconnective surgery with the improving surgical techniques.

Epilepsy is a common disease. WHO data suggests that 1 in 20 people may have an epileptic seizure in their lifetime and at least 1 in 200 go on to develop epilepsy. Anticonvulsant drug therapy using one or more drugs works as an effective tool to suppress seizures in only 70% of the patients, the remaining 30% are either not responsive or suffer major side effects. Surgical resection then forms the next line of management in selected patients. However in some cases surgical resection may not be possible, hence arises the need for alternative therapies. Neuromodulation of the Central Nervous system is a novel technique under evaluation for Medically Intractable epilepsy. CNS stimulation for epilepsy has been a matter of extensive research. We review the Neurophysiological basis of Neuromodulation in Epilepsy and various modalities viz Vagal nerve stimulation (VNS), Transcranial magnetic stimulation (TMS) and Direct cortical stimulation (DCS). Deep brain stimulation (Hippocampal, Anterior thalamic and STN) and RNS are newer modalities and are also reviewed.

Background: Prediction of the long-term outcomes of childhood-onset epilepsy remains crucial for the future well-being of the affected children and their families and for planning proper therapeutic and educational programs. Objective: To identify and analyze the early predictive factors of seizure control in childhood-onset epilepsies referred at the age of 1 month up to the age of 18 years to the Epilepsy Service at the Meyer Children Hospital, Rambam Medical Center, Haifa, Israel. Materials and Methods: In this study, children who were newly diagnosed with epileptic disorders and treated with antiepileptic drug therapy - who became either completely controlled for at least twelve months or those remaining intractable - were included. Partially responding children were excluded from the analysis. The etiology was segregated into either symptomatic or nonsymptomatic epilepsy, referred to as idiopathic epilepsy. Results: Overall, 74 children (mean age: 4.27 ± 4 years at the first seizure) were found eligible for analysis followed for a mean period of 4.5 years. Fifty-three (72%) children became seizure-free for a mean period of 20 months on antiepileptic drug (AED) therapy and 21 (28%) remained uncontrolled. Sixty out of 74 children (81%) had idiopathic epilepsy and 14 (19%) had symptomatic epilepsy. In those with idiopathic epilepsy, 46 (77%) children gained complete seizure control in comparison to 7 out of 14 (50%) children in the symptomatic group ( P < 0.01). Thirty-nine out of 47 (83%) children who had normal cognition became seizure-free, and 14 (52%) out of 27 mentally retarded children also became seizure-free ( P < 0.01). The outcome of seizure control was not affected by age at onset and seizure type itself during the presentation. Conclusion: The present study reveals that the single most predictive factor of a favorable seizure control is preserved cognitive function in accordance with idiopathic epilepsy. However, a fairly high number of children with impaired cognition may also achieve satisfactory seizure control.

Object: Despite advancement in neuroimaging and improvement in the knowledge of tumor behavior, the optimal surgical treatment of patients with temporal-lobe tumors remains unclear. Controversies still exist regarding the type of tumor surgery, i.e., lesionectomy alone or in combination with resection of mesial temporal structures and epileptogenic cortex adjacent to the tumor and the extent of tumor removal. In this retrospective study, the authors have analyzed seizure outcome in a series of children with epileptogenic temporal lobe tumors who had been treated only by lesionectomy. Materials and Methods: Sixteen patients including 7 boys and 9 girls, with a mean age of 9.9 years (range: 5-17 years) underwent lesionectomy as the only surgical treatment for temporal lobe tumor related epilepsy. The interval between onset of seizures and surgery ranged from 3 months to 7.5 year (mean 5.9 year). Ten patients (62.5%) presented with complex partial seizures and the remaining 6 (37.5%) had simple partial seizures with secondary generalization, with seizure frequency varying from several per day to only a few per month. All tumors were located within the temporal lobes: 8 temporomesial, 5 temporolateral and 3 temporobasal. Cortical dysplasia adjacent to tumor, hippocampal sclerosis or tumor infiltration was not demonstrated in any patient. Results: Gross total resection of the tumor was achieved in 11 (69%) and subtotal resection in 5 (31%) patients. The histopathological diagnosis was ganglioglioma in 6 (37.5%) patients, dysembryoplastic neuroepithelial tumor in 5 (31.3%), low-grade astrocytoma in 2 (12.5%), juvenile pilocytic astrocytoma in 2 (12.5%) and pleomorphic xanthoastrocytoma in 1 (6.3%). At a mean follow-up of 5.2 years (range, 1.4-9.3 years), 11 (69%) patients were seizure-free (Engel class I) and 4 (25%) others had a significant improvement in the seizure frequency (Engel class II). Conclusions: The results of this study suggest that good long-term seizure control can be achieved with lesionectomy alone in majority of children suffering from medically resistant epilepsy associated with temporal lobe tumors.