The effect of age on seizure semiology in childhood temporal lobe epilepsy

Escaping the Procrustean Bed: A Perspective on Pediatric Stereoelectroencephalography

SUMMARY

Stereoelectroencephalography is an established, hypothesis-driven method for investigating refractory epilepsy. There are special considerations and some limitations that apply to children who undergo stereoelectroencephalography. A key principle in stereoelectroencephalography is taking an individualized approach to investigating refractory epilepsy. A crucial factor for success in a personalized pediatric epilepsy surgery is understanding some of the fundamental and unique aspects of it, including, but not limited to, diverse etiology, epilepsy syndromes, maturation, and age-related characteristics as well as neural plasticity. Such features are reflected in the ontogeny of semiology and electrophysiology. In addition, special considerations are taken into account during cortical stimulation in children. Stereoelectroencephalography can guide a tailored surgical intervention where it is sufficient to render the patient seizure-free but it also lessens collateral damage with a minimum or no functional deficit. Epilepsy surgery outcomes remain stagnant despite advances in noninvasive testing modalities. A stereoelectroencephalography "way of thinking" and guided mentorship may influence outcomes positively.

Machine learning to support triage of children at risk for epileptic seizures in the pediatric intensive care unit

OBJECTIVE

Epileptic seizures are relatively common in critically-ill children admitted to the pediatric intensive care unit (PICU) and thus serve as an important target for identification and treatment. Most of these seizures have no discernible clinical manifestation but still have a significant impact on morbidity and mortality. Children that are deemed at risk for seizures within the PICU are monitored using continuous-electroencephalogram (cEEG). cEEG monitoring cost is considerable and as the number of available machines is always limited, clinicians need to resort to triaging patients according to perceived risk in order to allocate resources. This research aims to develop a computer aided tool to improve seizures risk assessment in critically-ill children, using an ubiquitously recorded signal in the PICU, namely the electrocardiogram (ECG).

APPROACH

A novel data-driven model was developed at a patient-level approach, based on features extracted from the first hour of ECG recording and the clinical data of the patient.

MAIN RESULTS

The most predictive features were the age of the patient, the brain injury as coma etiology and the QRS area. For patients without any prior clinical data, using one hour of ECG recording, the classification performance of the random forest classifier reached an area under the receiver operating characteristic curve (AUROC) score of 0.84. When combining ECG features with the patients clinical history, the AUROC reached 0.87.

SIGNIFICANCE

Taking a real clinical scenario, we estimated that our clinical decision support triage tool can improve the positive predictive value by more than 59% over the clinical standard.

Deep Convolutional Gated Recurrent Unit Combined with Attention Mechanism to Classify Pre-Ictal from Interictal EEG with Minimized Number of Channels

The early prediction of epileptic seizures is important to provide appropriate treatment because it can notify clinicians in advance. Various EEG-based machine learning techniques have been used for automatic seizure classification based on subject-specific paradigms. However, because subject-specific models tend to perform poorly on new patient data, a generalized model with a cross-patient paradigm is necessary for building a robust seizure diagnosis system. In this study, we proposed a generalized model that combines one-dimensional convolutional layers (1D CNN), gated recurrent unit (GRU) layers, and attention mechanisms to classify preictal and interictal phases. When we trained this model with ten minutes of preictal data, the average accuracy over eight patients was 82.86%, with 80% sensitivity and 85.5% precision, outperforming other state-of-the-art models. In addition, we proposed a novel application of attention mechanisms for channel selection. The personalized model using three channels with the highest attention score from the generalized model performed better than when using the smallest attention score. Based on these results, we proposed a model for generalized seizure predictors and a seizure-monitoring system with a minimized number of EEG channels.

Seizure semiology, localization, and the 2017 ILAE seizure classification

In the study of epilepsy, the term semiology is used to comprise the clinical characteristics of a seizure, both subjective symptoms and objective phenomena. It is produced by activation of the symptomagenic zone, and an accurate and comprehensive understanding of the localizing value of seizure semiology is crucial for presurgical evaluation and planning. Myriad publications in epilepsy journals detail correlations between various semiological features and activation of specific cortical regions. Traditionally these studies involved scalp EEG recorded in epilepsy monitoring units. The increasing use of invasive monitoring, and specifically the use of depth electrodes and stereo-electroencephalography, has advanced our understanding of the characteristics of seizures arising from ictal foci deep to the scalp, including the cingulate, insula and operculum. However, the distinction between seizure onset and symptomogenic zones is not always clear. In 2017 the International League Against Epilepsy (ILAE) published an operational classification of seizure types based heavily on seizure semiology. The current paper provides an updated review of the current body of knowledge relating to seizure semiology, incorporating both scalp EEG studies and more recent stereo-electroencephalography discoveries in the framework of the 2017 ILAE classification.

Comparison of traditional and closed loop vagus nerve stimulation for treatment of pediatric drug-resistant epilepsy: A propensity-matched retrospective cohort study

OBJECTIVE

For epilepsy patients with drug-resistant, unresectable epilepsy, vagus nerve stimulation (VNS) is an option for seizure control. Approximately 40-70% of patients will achieve ≥50% seizure reduction with VNS. New closed loop VNS models detect ictal tachycardia and responsively stimulate the vagus nerve. The effectiveness of closed loop VNS compared to traditional VNS for pediatric epilepsy is unknown.

METHODS

An 11-year retrospective electronic medical record review at Children's Hospital of Pittsburgh was performed. Patients with drug-resistant epilepsy who underwent VNS implantation were included. Patients were divided into groups based on VNS model: traditional versus closed loop. Those who transitioned from traditional to closed loop VNS were excluded. Given potential for selection bias, propensity scores matching was utilized to compare traditional to closed loop VNS patients. Patients with focal versus generalized epilepsy were also separately analyzed. The primary outcome was "VNS response", defined as at least 50% seizure frequency reduction from baseline.

RESULTS

A total of 320 patients were included in this sample. The percentage of matched patients (total n = 220: n = 179 traditional VNS, n = 41 closed loop VNS) who responded to VNS after one year of therapy was 43% for traditional VNS and 39% for closed loop VNS (p = 0.64). After two years of therapy, a higher proportion of closed loop VNS patients than traditional VNS patients responded to VNS among all subgroups, though no differences were statistically significant (p>0.05). Notably, for those with generalized epilepsy, 73% of closed loop patients responded to VNS compared to only 46% of traditional patients (p = 0.10). After two years of VNS therapy, patients were taking approximately the same quantity of antiseizure medications as baseline (change of +0.074 +/- 0.90 ) with no difference between VNS models (p = 0.87).

SIGNIFICANCE

Among pediatric patients with drug-resistant epilepsy, closed loop VNS trends towards a higher rate of VNS response after two years of treatment, especially among generalized epilepsy patients. Neither model of VNS allows patients to reduce antiseizure medication quantity after two years.

Risk Factors for Drug Resistance in Epileptic Children with Age of Onset above Five Years: A Case-Control Study

Background

Children with epilepsy with onset above five years encompass distinct epidemiological and clinical characteristics that may have specific risk factors for resistance to antiseizure medications (ASMs). Studies on this age group are limited.

Purpose

To identify risk factors for drug resistance in children with epilepsy with the age of onset above five years.

Methods

A case-control study was conducted on children with epilepsy with the age of onset above five years visiting the Pediatric Neurology Clinic of Cipto Mangunkusumo and Mohammad Hoesin Hospital between September 2015 and August 2016. Cases consisted of drug-resistant children while control consisted of drug-responsive children according to 2010 ILAE classification. Risk factors studied include onset, number of seizures, illness duration before treatment, cause, seizure type, status epilepticus, initial and evolution of EEG, brain imaging, and initial treatment response.

Results

Thirty-two pairs of children were included in the study. After logistic regression analysis, symptomatic etiology and failure to achieve early response to treatment were found to be associated with drug resistance with adjusted OR of 84.71 (95% CI: 5.18-1359.15) and 72.55 (95% CI: 7.08-743.85), respectively.

Conclusion

Poor initial response to ASM and symptomatic etiology are independent risk factors for drug resistance in children with epilepsy with the age of onset above five years.

Towards a pragmatic epilepsy classification: Future considerations

The Integrated Epilepsy Classification was recently proposed to merge the 2017 International League Against Epilepsy classification and the four-dimensional epilepsy classification updated in 2019. The efforts in developing the concept of an Integrated Epilepsy Classification scheme are encouraging. However, consideration of brain age, validation in contexts that differ in socioeconomic status and with poor healthcare infrastructure, and incorporation of a team-based approach are necessary. These advancements allow for better clinical management of people with epilepsy and empower people with epilepsy globally.

Electroclinical features of insulo-opercular epilepsy: an SEEG and PET study

Objective

To report clinical experience with presurgical evaluation in patients with insulo‐opercular epilepsy. Quantitative analysis on PET imaging and stereoelectroencephalography (SEEG) signals was used to summarize their electroclinical features.

Methods

Twenty‐two patients with focal epilepsy arising from the insular and/or opercular cortex according to SEEG were retrospectively analyzed. Presurgical noninvasive data were analyzed in detail. Interictal PET data of patients were then statistically compared with those of healthy controls to identify the interictal hypometabolic network. The epileptogenicity index (EI) of ictal SEEG signal was computed to identify areas of spread at the beginning of seizure onset.

Results

Focal tonic seizures of the face and/or neck (16/22, 73%) were the most prevalent early objective signs. Epileptic discharges in the interictal and ictal scalp‐EEG mostly showed an ipsilateral perisylvian distribution. Statistical analysis of interictal PET showed significant hypometabolism in the insular lobe, central operculum, supplementary motor area, middle cingulate cortex, bilateral caudate nuclei, and putamen. According to the EI analysis, insulo‐opercular epilepsy could be classified as insulo‐opercular epilepsy (50%), opercular epilepsy (41%), and insular cortex epilepsy (9%).

Significance

Clinical diagnosis of insulo‐opercular epilepsy is challenging because of its complex seizure semiology and nonlocalizing discharges on scalp‐EEG. A common hypometabolic network involving the insulo‐opercular cortex, mesial frontal cortex and subcortical nuclei may be involved in the organization of the insulo‐opercular epilepsy network. Furthermore, quantified SEEG analysis suggested that pure insular epilepsy is rare, and the close connection between insular and opercular cortex necessitates SEEG implantation to define the epileptogenic zone.

Initial clinical presentation of young children with N-methyl-d-aspartate receptor encephalitis

Autoimmune encephalitis with anti-N-methyl-d-aspartate receptor autoantibodies (NMDA-R-Abs) is a recently described disease affecting adult and pediatric patients. Symptoms of the disease are now perfectly described in the adult population but the clinical presentation is less known in young children. The aim of the present study was to describe the clinical presentation and the specificities of symptoms presented by young children with NMDA-R-Abs encephalitis to improve diagnosis of this disease, and to compare these to a series of previously published female adult patients. Fifty cases of children younger than twelve years of age diagnosed with NMDA-R-Abs encephalitis between January 1, 2007 and December 31, 2016 (27 females and 23 males) were retrospectively studied. The first neurological symptoms observed in young children with NMDA-R-Abs encephalitis were characterized by seizure (72%), especially focal seizure (42%), within a median of 15 days before other encephalitis symptoms; other patients mostly had behavioral disorders (26%). The seizures were frequently difficult to diagnose because of the transient unilateral dystonic or tonic posturing presentation or sudden unilateral pain in the absence of clonic movements. A post-ictal motor deficit was also frequently observed. This clinical presentation is different from that observed in adult females with NMDA-R-Abs encephalitis who initially present mainly psychiatric disorders (67%) or cognitive impairment (19%), and less frequently seizures (14%). The diagnosis of NMDA-R-Abs encephalitis should be systematically considered in young children of both sexes who present neurological symptoms suggesting recent seizures (focal or generalized) without obvious other etiology.

Clinical Drug Development in Epilepsy Revisited: A Proposal for a New Paradigm Streamlined Using Extrapolation

Data from clinical trials in adults, extrapolated to predict benefits in paediatric patients, could result in fewer or smaller trials being required to obtain a new drug licence for paediatrics. This article outlines the place of such extrapolation in the development of drugs for use in paediatric epilepsies. Based on consensus expert opinion, a proposal is presented for a new paradigm for the clinical development of drugs for focal epilepsies. Phase I data should continue to be collected in adults, and phase II and III trials should simultaneously recruit adults and paediatric patients aged above 2 years. Drugs would be provisionally licensed for children subject to phase IV collection of neurodevelopmental safety data in this age group. A single programme of trials would suffice to license the drug for use as either adjunctive therapy or monotherapy. Patients, clinicians and sponsors would all benefit from this new structure through cost reduction and earlier access to novel treatments. Further work is needed to elicit the views of patients, their parents and guardians as appropriate, regulatory authorities and bodies such as the National Institute for Health and Care Excellence (UK).

Hyperthermia-Induced Febrile Seizures Have Moderate and Transient Effects on Spatial Learning in Immature Rats

The aim of this study was to characterize a novel animal model hyperthermia-induced febrile seizure and to investigate the impacts of repetitive febrile seizures on spatial learning and memory performances in immature rats. Methods. Rats were subjected to hyperthermia exposure one, two, or three times in 10-day intervals during 30 min in a water bath warmed at 45–50°C and their behaviour was monitored. Morris water maze spatial learning and memory were examined for control and treated groups. Results showed that rats subjected to 30-minute hyperthermia hot water developed rapidly myoclonic jerks and then generalized seizures. After a single hyperthermia exposure, the time for generalised tonic-clonic seizures appearance was 16.08 ± 0.60 min and it decreased gradually with repetitive exposure to reach 12.46 ± 0.39 min by the third exposure. Febrile seizures altered the spatial learning and memory abilities in Morris water maze and increased the time spent to attain the platform after one or two exposures, while after a third exposure rats exhibited the same latency compared to controls. Similar results were obtained in probe test where rats, subjected to hyperthermia for one or two episodes, spent less time in the target quadrant compared to corresponding controls. Further, when platform was moved from northwest to southwest quadrant, memory transfer test indicated that after one or two hyperthermia exposures cognitive performances were slightly altered, while after a third exposure the latency to escape increased significantly compared to untreated group. It was concluded that 30 min of hyperthermia hot water was sufficient to induce febrile seizures in immature rats and an increase of susceptibility was observed with repetitive hyperthermia exposure. Hyperthermia treatment impaired cognitive performances but the effects were mostly transient and moderate.

Childhood temporal lobe epilepsy: correlation between electroencephalography and magnetic resonance spectroscopy: a case-control study

Background

The diagnosis of epilepsy should be made as early as possible to give a child the best chance for treatment success and also to decrease complications such as learning difficulties and social and behavioral problems. In this study, we aimed to assess the ability of magnetic resonance spectroscopy (MRS) in detecting the lateralization side in patients with Temporal lobe epilepsy (TLE) in correlation with EEG and MRI findings.

Methods

This was a case–control study including 40 patients diagnosed (clinically and by EEG) as having temporal lobe epilepsy aged 8 to 14 years (mean, 10.4 years) and 20 healthy children with comparable age and gender as the control group. All patients were subjected to clinical examination, interictal electroencephalography and magnetic resonance imaging (MRI). Proton magnetic resonance spectroscopic examination (MRS) was performed to the patients and the controls.

Results

According to the findings of electroencephalography, our patients were classified to three groups: Group 1 included 20 patients with unitemporal (lateralized) epileptic focus, group 2 included 12 patients with bitemporal (non-lateralized) epileptic focus and group 3 included 8 patients with normal electroencephalography. Magnetic resonance spectroscopy could lateralize the epileptic focus in 19 patients in group 1, nine patients in group2 and five patients in group 3 with overall lateralization of (82.5%), while electroencephalography was able to lateralize the focus in (50%) of patients and magnetic resonance imaging detected lateralization of mesial temporal sclerosis in (57.5%) of patients.

Conclusion

Magnetic resonance spectroscopy is a promising tool in evaluating patients with epilepsy and offers increased sensitivity to detect temporal pathology that is not obvious on structural MRI imaging.

Temporal lobe epilepsy in infants and children

Clinical expression of temporal lobe seizures is different with a more diverse and more extensive etiology in infants and children than it is in adults. It is dominated by cortical dysplasia, low-grade tumors and perinatal damage. Hippocampal sclerosis, although less frequent, exists in children usually as a dual pathology associated with ipsilateral neocortical lesions. The clinical semiology of temporal seizures is more varied, and sometimes misleading. Motor features including tonic, clonic or myoclonic behaviors, and infantile spasms predominate in infants. Classical complex partial seizures with behavioral arrest and automatisms, as well as lateralizing signs are rare and occur mostly with onset after the age of two years. Interestingly, aura, emotional, and autonomic signs seem to be independent on the brain maturation process. Moreover, the neuropsychological profile varies according to age of onset and duration, lateralization of the focus and etiology. Quality of care benefits from individual cognitive assessment for memory and emotional processes.

Seizure Semiology: Value in Identifying Seizure Origin

The diagnosis of epilepsy depends upon a number of factors, particularly detailed and accurate seizure history, or semiology. Other diagnostic data, consisting of electroencephalography, video-monitoring of the seizures, and magnetic resonance imaging, are important in any comprehensive epilepsy program, particularly with respect to lateralizing and localizing the seizure focus, if such a focus exists, and with respect to determining the type of seizure or seizure syndrome. The aim of this review is to present a survey of important semiologic characteristics of various seizures that provide the historian with observations, which help to lateralize and localize epileptic zones. Clinical semiology is the starting point of understanding a seizure disorder and making the diagnosis of epilepsy. While it may not provide unequivocal evidence of localization of the epileptic focus, nevertheless it usually directs subsequent investigations, whose concordance is necessary for the ultimate localization.

Electro-clinical-pathological correlations in focal cortical dysplasia (FCD) at young ages

The prevalence of focal cortical dysplasia (FCD) in pediatric patients with focal epilepsy is not exactly known because authors of publications in which the etiologies of epilepsies are listed, but which are not dealing specifically with epilepsy surgery issues, tend to lump together the many kinds of malformations of cortical development (MCD), of which FCDs, because of their relative frequency, are the most relevant subtypes. Out of 561 patients with MCD (children and adults) operated at centers in Europe who do feed data into the "European Epilepsy Brain Bank," 426 (76 %) had FCD.

Video electroencephalogram telemetry in temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most commonly encountered medically refractory epilepsy. It is also the substrate of refractory epilepsy that gives the most gratifying results in any epilepsy surgery program, with a minimum use of resources. Correlation of clinical behavior and the ictal patterns during ictal behavior is mandatory for success at epilepsy surgery. Video electroencephalogram (EEG) telemetry achieves this goal and hence plays a pivotal role in pre-surgical assessment. The role of telemetry is continuously evolving with the advent of digital EEG technology, of high-resolution volumetric magnetic resonance imaging and other functional imaging techniques. Most of surgical selection in patients with TLE can be done with a scalp video EEG monitoring. However, the limitations of the scalp EEG technique demand invasive recordings in a selected group of TLE patients. This subset of the patients can be a challenge to the epileptologist.

Clinical and ictal characteristics of infantile seizures: EEG correlation via long-term video EEG monitoring

PURPOSE

The semiology of infantile seizures often shows different characteristics from that of adults. We performed this study to describe clinical and ictal characteristics of infantile seizures at less than two years of age.

METHODS

A retrospective study was done for infants with epilepsy (ages: 1-24months) who underwent long-term video electroencephalography (EEG) monitoring at Samsung medical center between November 1994 and February 2012. We analyzed the clinical and ictal characteristics of the 56 cases from 51 patients.

RESULTS

In 69% of the patients, the seizure onset was before six months of age and the etiology was symptomatic in one third of the patients. Twelve seizure types were identified; spasms (24%), unilateral motor seizures (18%), and generalized tonic seizures (15%) were the three frequent types of seizure. All partial seizures were well correlated with the partial-onset ictal EEG, however 19.4% (7/36) of clinically generalized seizures revealed partial-onset ictal EEG. About one-thirds (4/11) of generalized tonic seizures had its ictal onset on unilateral or bilateral frontal areas and two out of seven generalized myoclonic seizures showed unilateral frontal rhythmic activities. Hypomotor seizures mainly arose from the temporal areas and hypermotor seizures from the frontal regions.

CONCLUSIONS

Even though most of the seizure semiology of infants is well correlated with ictal EEG, some of the generalized tonic seizures or myoclonic seizures revealed partial-onset ictal EEG suggesting localized epileptic focus. Accurate definition of seizures via video EEG monitoring is necessary for proper management of seizures in infancy, especially in some clinically generalized seizures.

Mesial temporal lobe epilepsy

Temporal lobe epilepsy (TLE) is the most common form of adult localization-related epilepsy. Hippocampal onset accounts for at least 80% of all temporal lobe seizures. The electroencephalogram (EEG) of mesial TLE contains interictal features often associated with anterior temporal epileptiform discharges with a maximal voltage over the basal temporal electrodes. Localized ictal patterns on scalp EEGs characteristically reveal unilateral 5- to 9-Hz rhythmic ictal theta or alpha epileptiform activity maximal in the anterior temporal scalp electrodes. Invasive-scalp EEG comparisons have yielded direct information about mesial temporal sources and their corresponding electrical fields. Refinement of macroscopic spatial and the temporal resolution suggest that a more precise seizure localization may exist beyond 1- to 35-Hz frequencies observed in routine scalp recording. Defining the focal areas of ictogenesis within the medial temporal lobe demonstrates a rich connection to a broad network that goes beyond the medial structures and even the temporal lobe itself. Advanced electrophysiologic application in TLE may further our understanding of ictogenesis to perfect surgical treatment and to elucidate the neurophysiologic corollaries of epileptogensis itself.

Surgery for temporal lobe epilepsy in children: relevance of presurgical evaluation and analysis of outcome

OBJECT

The authors' goal in this paper was to retrospectively evaluate the relevance of the presurgical workup and the postoperative outcome in children (< 15 years) who undergo surgery for temporal lobe epilepsy (TLE).

METHODS

The authors performed a retrospective analysis of 68 patients (43 boys and 25 girls) who underwent resection for TLE between 2001 and 2010 at a single center and had a minimum postoperative follow-up of 12 months. Presurgical investigations included full clinical evaluation, interictal electroencephalography (EEG), and MRI in all cases; cognitive evaluation in patients older than 5 years; scalp video-EEG in 46 patients; and invasive EEG in 3 patients. Clinical evaluation included a careful assessment of ictal semiology (based on anamnestic reports or video-EEG review), with particular attention to early signs and/or symptoms suggestive of temporal lobe origin of the seizure. Microsurgical resections were performed within the anatomical limits of the temporal lobe, and surgical specimens were processed for histological examination. Postoperative assessment of seizure outcome (Engel classification system) and cognitive performance was conducted at regular intervals. The effect on postoperative seizure outcome (good = Engel Class I; poor = Engel Classes II-IV) of several presurgical and surgical variables was investigated by bivariate statistical analysis.

RESULTS

All patients had at least 1 early sign or symptom suggesting a temporal lobe origin of their seizures. Lateralized interictal or ictal EEG abnormalities were seen in all patients, and they were localized to the temporal lobe in 45 patients. In all cases MRI demonstrated a structural abnormality. Surgery consisted of a tailored anterior temporal lobectomy in 64 patients and a neocortical lesionectomy in 4 patients. Postoperatively, 58 patients (85%) were in Engel Class I. Variables significantly associated with a poor outcome were preoperative sensory motor deficit (p = 0.019), mental retardation (p = 0.003), MRI abnormalities extending outside the temporal lobe (p = 0.0018), history of generalized seizures (p = 0.01) or status epilepticus (p = 0.008), unremarkable histology (p = 0.001), seizures immediately postoperatively (p = 0.00001), and ipsilateral epileptiform activity on postoperative EEG (p = 0.005). At postoperative neuropsychological assessment, the percentage of patients with a pathological score at the final visit invariably decreased compared with that at the preoperative evaluation in all considered cognitive domains.

CONCLUSIONS

Among the study population, a surgical selection based on a noninvasive evaluation was possible in most patients. The invaluable information resulting from the rigorous noninvasive electroclinical and neuroimaging evaluation can lead to excellent surgical results without the use of invasive, time-consuming, and expensive diagnostic tools. The potential reduction of invasiveness-related risks, complexity, and costs of presurgical investigations should hopefully allow for an increase in the number of children with TLE who will receive surgery, particularly in centers with limited technological resources.

Temporal lobe epilepsy semiology

Epilepsy represents a multifaceted group of disorders divided into two broad categories, partial and generalized, based on the seizure onset zone. The identification of the neuroanatomic site of seizure onset depends on delineation of seizure semiology by a careful history together with video-EEG, and a variety of neuroimaging technologies such as MRI, fMRI, FDG-PET, MEG, or invasive intracranial EEG recording. Temporal lobe epilepsy (TLE) is the commonest form of focal epilepsy and represents almost 2/3 of cases of intractable epilepsy managed surgically. A history of febrile seizures (especially complex febrile seizures) is common in TLE and is frequently associated with mesial temporal sclerosis (the commonest form of TLE). Seizure auras occur in many TLE patients and often exhibit features that are relatively specific for TLE but few are of lateralizing value. Automatisms, however, often have lateralizing significance. Careful study of seizure semiology remains invaluable in addressing the search for the seizure onset zone.

Temporal lobe epilepsy in children

The temporal lobe is a common focus for epilepsy. Temporal lobe epilepsy in infants and children differs from the relatively homogeneous syndrome seen in adults in several important clinical and pathological ways. Seizure semiology varies by age, and the ictal EEG pattern may be less clear cut than what is seen in adults. Additionally, the occurrence of intractable seizures in the developing brain may impact neurocognitive function remote from the temporal area. While many children will respond favorably to medical therapy, those with focal imaging abnormalities including cortical dysplasia, hippocampal sclerosis, or low-grade tumors are likely to be intractable. Expedient workup and surgical intervention in these medically intractable cases are needed to maximize long-term developmental outcome.

Mesial temporal lobe epilepsy with hippocampal sclerosis: study of 42 children

PURPOSE

We present the electroclinical features, treatment, and evolution of patients with mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS).

MATERIAL AND METHODS

We analyzed the charts of forty-two patients who met the diagnostic criteria of MTLE-HS. The mean follow-up after seizure onset was 10.5 years.

RESULTS

According to age, we defined three groups. The first group included nine patients that started with seizures before 2 years of age. Motor seizures were the hallmark clinical manifestation. All patients of this group also presented with motor arrest and oro-alimentary automatisms. In three of them, the interictal EEG recordings showed bilateral paroxysms predominantly in anterior regions, in addition to focal abnormalities, and two had an apparently generalized ictal pattern. The second group included 17 patients that started with seizures between 2 and 10 years of age. In this group the automatisms were also oroalimentary, but more complex and the patients had less motor manifestations. The interictal EEG recordings showed temporal abnormalities. The ictal EEG recordings showed lateralized abnormalities with a maximum in the temporal electrodes. The third group included 16 patients that started with seizures between 10 and 16 years of age. The most common clinical manifestation was abdominal aura followed by oroalimentary, gestural, and verbal automatisms. The interictal and ictal EEG recordings showed well-localized abnormalities in temporal lobes. Thirty-eight patients underwent surgical treatment. Thirty-five patients are seizure free.

CONCLUSION

MTLE-HS represents a well-defined and distinct symptomatic epileptic syndrome. Surgical treatment was successful in most patients.

Semiology of epileptic seizures: a critical review

Epileptic seizures are characterized by a variety of symptoms. Their typical semiology served for a long time as the major tool to classify epilepsy syndromes. The signs and symptoms of epileptic seizures include the following spheres: sensorial sphere, consciousness, motor and autonomic spheres. Most seizures involve more than one sphere, however, some like for instance aura (sensorial sphere) or dialeptic seizures (consciousness) involve only one sphere. The predominant clinical features of a seizure determines the seizure classification. The following review gives an introduction into the semiological seizure classification. This approach enables us to better identify the epileptogenic zone of our patients and to choose the most effective medical or surgical treatment.

Two new familial severe infantile spasm syndromes in males

We describe two new familial severe infantile spasm syndromes (ISSs) unrelated to Aristaless-related homeobox (ARX) gene mutation. Family A contains two male siblings each with dysmorphism, profound psychomotor delay, gastroesophageal reflux, infantile spasms, hypsarrhythmia, prominent independent central apneas, and early death. Family B contains two male siblings with dysmorphism, profound psychomotor delay, ambiguous genitalia, macular hypoplasia, neurosensory hearing deficit, gastroesophageal reflux, infantile spasms, no hypsarrhythmia, apneas, and early death in one sibling. Etiologic workup and ARX gene sequencing were negative. This indicates that several familial ISSs exist but are not genetically characterized.

The masquerades of temporal lobe epilepsy in childhood

Age-Dependent Seizure Semiology in Temporal Lobe Epilepsy. Fogarasi A, Tuxhorn I, Janszky J, Janszky I, Rásonyi G, Kelemen A, Halász P. Epilepsia 2007;48(9):1697–1702. Epub 2007 May 23. OBJECTIVE: To examine the effects of age on different aspects of temporal lobe seizure semiology. METHODS: We performed a video analysis of 605 archived seizures from 155 consecutive patients (age 10 months to 49 years) selected by seizure freedom after temporal lobectomy. Eighty patients had hippocampal sclerosis (HS). Beside semiological seizure classification, we assessed age dependency of several axes of seizure semiology: ( 1 ) aura, ( 2 ) number of different lateralizing signs, occurrence of ictal ( 3 ) emotional signs, ( 4 ) autonomic symptoms, ( 5 ) automatisms, and ( 6 ) secondary generalization as well as ( 7 ) the ratio of motor seizure components. RESULTS: From the 155 patients, 117 reported aura, 39 had ictal emotional signs, 51 had autonomic symptoms, 130 presented automatisms, while 18 patients showed secondary generalization at least once during their seizures. Altogether 369 (median: 2/patient) different lateralizing signs were recorded. Frequency of HS (p < 0.001), ictal automatisms (p < 0.001), secondary generalization (p = 0.014), number of different lateralizing signs (p < 0.001) increased while the ratio of motor seizure component (p = 0.007) decreased by age. Auras, emotional symptoms, and autonomic signs occurred independently of patients’ ages. Hippocampal sclerosis adjusted linear models revealed that the frequency of automatisms and secondarily generalized seizures as well as the number of different lateralizing signs are HS-independent significant variables. CONCLUSION: Our findings support that brain maturation significantly influences the evolution of some important aspects (motor seizures, lateralizing signs) of temporal lobe seizure semiology. Conversely, other aspects (aura, emotional, and autonomic signs) are independent of the maturation process. This is the first report investigating age dependency of epileptic seizure semiology comparing all age groups.

Age-Dependent Seizure Semiology in Temporal Lobe Epilepsy

OBJECTIVE

To examine the effects of age on different aspects of temporal lobe seizure semiology.

METHODS

We performed a video analysis of 605 archived seizures from 155 consecutive patients (age 10 months to 49 years) selected by seizure freedom after temporal lobectomy. Eighty patients had hippocampal sclerosis (HS). Beside semiological seizure classification, we assessed age dependency of several axes of seizure semiology: (1) aura, (2) number of different lateralizing signs, occurrence of ictal (3) emotional signs, (4) autonomic symptoms, (5) automatisms, and (6) secondary generalization as well as (7) the ratio of motor seizure components.

RESULTS

From the 155 patients, 117 reported aura, 39 had ictal emotional signs, 51 had autonomic symptoms, 130 presented automatisms, while 18 patients showed secondary generalization at least once during their seizures. Altogether 369 (median: 2/patient) different lateralizing signs were recorded. Frequency of HS (p < 0.001), ictal automatisms (p < 0.001), secondary generalization (p = 0.014), number of different lateralizing signs (p < 0.001) increased while the ratio of motor seizure component (p = 0.007) decreased by age. Auras, emotional symptoms, and autonomic signs occurred independently of patients' ages. Hippocampal sclerosis adjusted linear models revealed that the frequency of automatisms and secondarily generalized seizures as well as the number of different lateralizing signs are HS-independent significant variables.

CONCLUSION

Our findings support that brain maturation significantly influences the evolution of some important aspects (motor seizures, lateralizing signs) of temporal lobe seizure semiology. Conversely, other aspects (aura, emotional, and autonomic signs) are independent of the maturation process. This is the first report investigating age dependency of epileptic seizure semiology comparing all age groups.

Ictal Emotional Expressions of Children with Partial Epilepsy

OBJECTIVE

To systematically analyze the lateralizing and localizing value of ictal emotional expressions (EEs) in children and compare these results with those of earlier adult studies.

METHODS

Five hundred fourteen seizures of 100 consecutive children < or = 12 years with partial (61/100 temporal lobe) epilepsy and postoperative seizure free outcome were included in the study. Video recordings of seizures were reviewed by two independent investigators blinded to the patients' clinical data.

RESULTS

Thirty-five patients produced EE at least once during their archived seizures, including fear (15), crying (12), smile (9), pain (5), happiness (3), and laughing (in one case). Emotional symptoms were divided into two groups: positive (smile, laughing, and happiness) and negative EEs (fear, crying, and pain). Emotional expressions appeared more frequently during extratemporal (49%) than temporal (26%) lobe seizures (p < 0.05). Positive EEs had an extratemporal dominance (p < 0.05), while frequency of negative EEs did not localize the seizure onset zone. Assessing their lateralizing value, positive EEs were more frequent during right-sided seizures (p < 0.05) while negative EEs did not lateralize the seizure onset zone. Frequency of EEs were independent of patients' ages, age at epilepsy onset or duration of epilepsy.

CONCLUSION

This is the first comprehensive childhood study showing that ictal EEs are frequent in childhood and their localizing and lateralizing properties are different from those of adults.

Temporal Lobe Epilepsy in Children: Electroclinical Study of 77 Cases

PURPOSE

Temporal lobe epilepsy (TLE) is probably more difficult to recognize in children than in adults. In fact, ictal symptoms in children are less stereotyped and less obvious, and the neuropathological substrate is more heterogeneous than in adults. The aim of this study is to examine the relationships between etiology, age at onset and electroclinical findings in 77 children with TLE, 32 of whom were surgically treated.

METHODS

Electroclinical study including video-EEG recording of seizures in 77 children with TLE. The investigation focused on the first five initial ictal symptoms.

RESULTS

Age at onset was less than 3 years in 39 cases, between 3 and 6 years in 17 cases and older than 6 years in 21 cases. Auras also occurred in younger children but were more common after the age of 6 years. A peculiar initial ictal semiology consisted in staring with arrest, lip cyanosis, and very slight oral automatisms. In some cases, EEG recordings documented seizures starting independently on both temporal lobes. Based on electroclinical and neuroradiological features, we recognized three subgroups: symptomatic TLE due to cortical malformations or nonevolutive tumors, TLE with mesial temporal sclerosis, and cryptogenic TLE.

CONCLUSIONS

A correct electroclinical and neuroradiological approach allows in several cases early recognition of TLE even when onset is earlier than the age of 6 years. A correct definition of the localization relies primarily on video-EEG recording of the seizures, possibly repeated during follow up in cases lacking obvious neuroradiological correlation.

Value and Limitations of Seizure Semiology in Localizing Seizure Onset

Seizure semiology has been the foundation of clinical diagnosis of seizure disorders. This article discusses the value and the limitations of behavioral features of seizure episodes in localizing seizure onset. Studies have shown that some semiologic features of seizures are highly accurate in the hemispheric lateralization and lobar localization of seizures. There is good agreement between blinded reviewers in lateralizing video-recorded seizures in temporal lobe and extratemporal lobe epilepsies. However, seizure semiology alone should not be used to determine the site of seizure onset. Each semiologic feature may falsely localize seizure onset. Seizure semiology in some patients may signify the site of seizure propagation rather than origination. Moreover, seizure semiology may not be as reliable in multifocal epilepsies as it is in unifocal epilepsies. Many semiologic features of seizures of adults are often missing in seizures of children. Seizure semiology should be analyzed and integrated with EEG and neuroimaging data to localize the seizure focus. A sample of the recorded seizures should be shown to the patient's relatives or friends to verify that it is representative of habitual seizures.

Interictal electroencephalographic findings in children and adults with temporal lobe tumors

OBJECTIVE

To characterize clinical and interictal electroencephalographic aspects of children and adults with temporal lobe epilepsy (TLE) due to tumoral lesions.

METHOD

We performed a retrospective analysis of the clinical and interictal electroencephalographic aspects of 16 children (64 exams) and 12 adults (78 exams) with lesions in the temporal lobe.

RESULTS

The most frequent etiologies were gangliogliomas, DNETs, followed by astrocytomas. Auras occurred in both groups, the most common being epigastric sensation. Other findings such as myoclonias, behavioral arrest and vomiting were more frequent in children. Temporal epileptiform and nonepileptiform activities, mostly unilateral, were found in both groups. Extratemporal epileptiform activities (frontal, parietal, central, occipital and generalized) were also found equally in both groups.

CONCLUSION

Our data show that children and adults with TLE due to expansive lesions present with similar EEG findings.

Treatment options and paradigms in childhood temporal lobe epilepsy

Temporal lobe epilepsy in adults is a relatively homogenous syndrome with hippocampal sclerosis being its most common pathologic substrate. In the pediatric age group, low-grade neoplasms and cortical dysplasia are much more common than hippocampal sclerosis. Pediatric temporal lobe epilepsy has distinct semiologic, electrophysiologic and imaging characteristics as compared with its adult counterpart. The various treatment options for pediatric temporal lobe epilepsy include antiepileptic drugs, resective surgery, vagal nerve stimulation and the ketogenic diet. In spite of the multiple antiepileptic drugs currently available, 5-10% of all newly diagnosed cases will remain intractable to medical therapy and should be referred for presurgical evaluation. Resective surgery offers the best chance of seizure freedom in carefully selected patients. Future areas of research include new drug development, better imaging and localization techniques, and brain stimulation.

Recessive symptomatic focal epilepsy and mutant contactin-associated protein-like 2

Contactin-associated protein-like 2 (CASPR2) is encoded by CNTNAP2 and clusters voltage-gated potassium channels (K(v)1.1) at the nodes of Ranvier. We report a homozygous mutation of CNTNAP2 in Old Order Amish children with cortical dysplasia, focal epilepsy, relative macrocephaly, and diminished deep-tendon reflexes. Intractable focal seizures began in early childhood, after which language regression, hyperactivity, impulsive and aggressive behavior, and mental retardation developed in all children. Resective surgery did not prevent the recurrence of seizures. Temporal-lobe specimens showed evidence of abnormalities of neuronal migration and structure, widespread astrogliosis, and reduced expression of CASPR2.

Autonomic Symptoms during Childhood Partial Epileptic Seizures

PURPOSE

To analyze systematically the occurrence and age dependence as well as the localizing and lateralizing value of ictal autonomic symptoms (ASs) during childhood partial epilepsies and to compare our results with those of earlier adult studies.

METHODS

Five hundred fourteen video-recorded seizures of 100 consecutive children 12 years or younger with partial epilepsy and seizure-free postoperative outcome were retrospectively analyzed.

RESULTS

Sixty patients produced at least one AS; 43 (70%) of 61 with temporal and 17 (44%) of 39 with extratemporal lobe epilepsy (p=0.012). Apnea/bradypnea occurred more frequently in younger children (p<0.01), whereas the presence of other ASs was neither age nor gender related. Postictal coughing (p<0.01) and epigastric aura (p<0.05) localized to the temporal lobe, whereas no ASs lateralized to the seizure-onset zone.

CONCLUSIONS

Our study shows that ASs are common in childhood focal epilepsies, appearing in infants and young children, too. As in adults, childhood central autonomic networks might have a close connection to temporal lobe structures but do not lateralize the seizure-onset zone. To our knowledge, this is the first study comprehensively assessing ASs in childhood epilepsy.

Predictive clinical factors for the differential diagnosis of childhood extratemporal seizures

PURPOSE

To describe predictive clinical factors for the differentiation between childhood frontal lobe epilepsy (FLE) and posterior cortex epilepsy (PCE).

METHODS

Two independent, blinded investigators analyzed 177 seizures from 35 children (aged 11 months to 12 years) with extratemporal epilepsy selected by postoperative seizure-free outcome. Semiologic seizure components and different periictal signs were observed. Age at onset, auras, seizure frequency, and nocturnal dominance, as well as surgical and histopathologic data, were collected from medical charts.

RESULTS

Twenty patients had FLE, and 15 had PCE. Patients from both groups had daily seizures without significant differences in frequency but with higher nocturnal dominance in children with FLE (p < 0.05). Visual aura, nystagmus, and versive seizure were observed exclusively in the PCE group, whereas somatosensory aura and hypermotor seizures appeared only in FLE. Tonic seizures were significantly more frequent in FLE (p < 0.01), whereas the presence of clonic seizure (FLE; p = 0.07) and postictal nose-wiping (PCE; p = 0.05) showed only a trend to localize the seizure-onset zone. Myoclonic seizures, epileptic spasms, psychomotor seizures, atonic seizures, oral and manual automatisms, as well as vocalization and eye deviation appeared in both groups without significant differences in their frequency.

CONCLUSIONS

Characteristic features described in adults' extratemporal epilepsies were frequently missing during childhood seizures, especially in infants and preschool children. Ictal features help only a little in differentiating childhood FLE from PCE. Nocturnal appearance and the type of aura have high localizing value; therefore an accurate history taking is still an essential element of pediatric presurgical evaluation.

Hyperorality in Epileptic Seizures: Periictal Incomplete Kluver-Bucy Syndrome

PURPOSE

To analyze systematically hyperorality associated with epileptic seizures and its relation to the localization of epileptic activity.

METHODS

To identify patients with periictal hyperorality, we reviewed video-recordings of 269 patients (aged 6-59 years) who had consecutively undergone presurgical evaluations including ictal video-EEG recordings and high-resolution magnetic resonance imaging (MRI) and had had epilepsy surgery because of intractable frontal (FLE) or temporal lobe epilepsy (TLE). Periictal hyperorality was defined if patients put or unambiguously intended to put nonfood items into their mouths during or after at least one of the reviewed seizures. For the further analysis, we included only patients with periictal hyperorality. We reviewed their medical records and reexamined their ictal video-EEG recordings.

RESULTS

We identified eight patients (six women) aged 8-59 years who had hyperorality during or after seizures. Seven patients had TLE, and one patient had frontal lobe epilepsy (FLE). Three of these patients underwent right-sided surgery, whereas five patients had surgery on the left. Three patients exhibited ictal and five showed postictal hyperorality. Interictal EEG suggested bilateral interictal epileptiform discharges (IEDs) in three patients; in two other patients, no IEDs were detected. Ictal EEG suggested bilateral involvement in six cases. Patients with unilateral epileptiform activity had left TLE.

CONCLUSIONS

Periictal hyperorality is a rare phenomenon occurring in 3% of the investigated epilepsy population. We suggest that periictal hyperorality is an ictal-postictal mental disturbance, an incomplete Klüver-Bucy syndrome. In most patients, bilateral seizure activity plays an important role in the pathomechanism, but it would appear that left-sided epileptic activity without contralateral involvement also can cause periictal hyperorality.

Genital automatisms in childhood partial seizures

PURPOSE

To describe frequency and electroclinical characteristics as well as localizing and lateralizing value of childhood periictal genital automatisms (GAs).

METHODS

Five-hundred-forty-one videotaped seizures of 109 consecutive patients <12 years with refractory partial epilepsy and postoperatively seizure-free outcome were analyzed. Genital automatisms (scratching, fondling or grabbing of the genitals) were monitored by two independent investigators.

RESULTS

Eight (four temporal, four extratemporal) patients (7%) showed GA at least once during 20 (3.7%) seizures. Age of patients with GA was between 4.5 and 11.9 (mean 9.5+/-2.4) years and was significantly higher than the age of children without GA (p=0.006). Boys showed GAs more frequently than girls (p=0.026). Genital automatisms appeared both ictally and postictally with a mean duration of 51s. They were unilateral (completed by one hand) in 18/20 seizures and were done by the hand ipsilateral to the seizure onset zone in 16/18 cases (p=0.001). Although consciousness was preserved during GA in 3/8 patients, neither periictal urinary urge nor penile erection was associated with it.

CONCLUSIONS

Periictal GAs appear in school-age patients with a similar frequency to that in adults but almost lack in preschool children. Although the presence of childhood GA has neither localizing nor lateralizing value per se, the hand used for GA is more frequently ipsilateral to the seizure onset zone. The mechanisms for childhood GAs are not clear but probably different from those of adults.

Hippocampal sclerosis in severe myoclonic epilepsy in infancy: a retrospective MRI study

PURPOSE

Severe myoclonic epilepsy in infancy (SMEI; Dravet's syndrome) is a malignant epilepsy syndrome characterized by early prolonged febrile convulsions (PFCs) with secondary psychomotor delay and a variety of therapy-resistant seizures. Although the initial symptoms are repeated PFCs, the MRI performed at the onset of disease shows no hippocampal structural abnormalities. We aimed to assess clinical and serial MRI data of patients with SMEI with a special attention to the temporomedial structures. To our knowledge, this is the first systematic MRI study in this disease.

METHODS

Clinical and MRI data of all SMEI patients treated in our hospitals between 1996 and 2004 were reviewed.

RESULTS

Twenty-eight MRIs from 14 children (one to four images/patient) were included. Age at disease onset was between 3 and 9 months; age at initial MRI was 5 months to 13 years. Ten of 14 patients showed hippocampal sclerosis (HS) during the course of the disease (nine unilateral, one bilateral). Six of these 10 had a normal initial MRI. Age at the first verified HS was between 14 months and 13 years. Neither complex partial seizures nor anterior temporal irritative zone was recorded in these children.

CONCLUSIONS

After initially normal structures, in most patients with SMEI, HS develops several months or years after the first PFC. These data support the hypothesis that PFC might be responsible for HS, but other factors and individual sensitivity should play a role in this process.

Ictal Smile Lateralizes to the Right Hemisphere in Childhood Epilepsy

PURPOSE

To analyze the localizing and lateralizing value of ictal smile (IS) in childhood epilepsy.

METHODS

Incidence of IS in 309 videotaped seizures of 114 consecutive patients younger than 12 years with refractory frontal, temporal, or posterior cortex epilepsy were assessed.

RESULTS

Among patients with right-sided epileptogenic zone, 12 (21%) of 57 had IS, whereas in patients with left-sided epilepsy, IS occurred only in one patient (1.8%; p < 0.01, chi(2) test). The incidence of IS was 11%, 3%, and 26% in the frontal, temporal, and posterior cortex subgroups, respectively. Logistic regression revealed that the localization of the epileptogenic region in the posterior cortex (p < 0.01), focal cortical dysplasia etiology (p = 0.012), and right-sided lateralization (p = 0.025) were independently associated with the presence of IS.

CONCLUSIONS

Childhood IS lateralizes to the right hemisphere and localizes more frequently in the posterior cortex epilepsy.

Clinical, electroencephalographic, and behavioral features of temporal lobe epilepsy in childhood

This study describes the clinical, electroencephalographic, and behavioral features of 36 children with temporal lobe epilepsy. Patients were divided into two groups: group A, with 6 patients (< 6 years), and group B, with 30 patients (6-18 years). Statistical analysis was performed considering the significance level of .05. Regarding the clinical features of the focal seizures, motor components were more frequently seen in children younger than 6 years of age (P < .01), whereas automatisms were more frequently seen in patients older than 6 years of age (P < .05). Associated myoclonic seizures were more frequent in the younger age group (P < .01). Behavioral disorders such as hyperactivity and aggressiveness and speech delay were more common in the younger age group (P < .05). Temporal lobe epilepsy in children younger than 6 years of age is more frequently associated with motor components, myoclonic seizures, behavioral disorders, and speech delay. Conversely, temporal lobe epilepsy in older patients has frequent automatisms.

The significance of ear plugging in localization-related epilepsy

PURPOSE

The localizing value of ear plugging in the treatment of auditory onset partial seizures, to our knowledge, has not been previously described. We propose that ear plugging is a clinical response to a sensory seizure manifested as an auditory hallucination and a tool for identifying the seizure focus in the auditory cortex on the superior temporal gyrus.

METHODS

We report on three children who had prior epilepsy surgery for recurrent symptomatic localization-related epilepsy and who, subsequent to their surgery, displayed stereotyped unilateral or bilateral ear plugging at the onset of partial seizures. We studied scalp video electroencephalography (VEEG), magnetoencephalography (MEG), and magnetic resonance imaging (MRI) in all three. Additionally, we used electrocorticography (ECoG) in two patients, intracranial VEEG monitoring in one patient, and functional MRI language mapping in two patients.

RESULTS

All three patients plugged their ears with their hands during auditory auras that localized to the superior temporal gyrus and were followed by partial seizures that spread to a wider field, as shown on scalp and intracranial VEEG. All three patients had MEG interictal discharges in the superior temporal gyrus. One patient who was nonverbal and unable to describe an auditory phenomenon plugged the ear contralateral to where temporal lobe-onset seizures and MEG interictal discharges occurred. CONCLUSIONS; Ear-plugging seizures indicate an auditory aura and may also lateralize seizure onset to the contralateral temporal lobe auditory cortex. Stereotyped behaviors accompanied by epileptic seizures in children who have poor communication skills are important in the seizure semiology of localization-related epilepsy.

Classification of seizures and epilepsy

The management of seizures and epilepsy begins with forming a differential diagnosis, making the diagnosis, and then classifying seizure type and epileptic syndrome. Classification guides treatment, including ancillary testing, management, prognosis, and if needed, selection of the appropriate antiepileptic drug (AED). Many AEDs are available, and certain seizure types or epilepsy syndromes respond to specific AEDs. The identification of the genetics, molecular basis, and pathophysiologic mechanisms of epilepsy has resulted from classification of specific epileptic syndromes. The classification system used by the International League Against Epilepsy is periodically revised. The proposed revision changes the classification emphasis from the anatomic origin of seizures (focal vs generalized) to seizure semiology (ie, the signs or clinical manifestations). Modified systems have been developed for specific circumstances (eg, neonatal seizures, infantile seizures, status epilepticus, and epilepsy surgery). This article reviews seizure and epilepsy classification, emphasizing new data.

A detailed analysis of symptomatic posterior cortex seizure semiology in children younger than seven years

PURPOSE

To analyze the semiology of seizure onset and evolution in young children with posterior cortex epilepsy (PCE), compare this with adult reports, and assess age-related differences.

METHODS

We videotaped and analyzed 110 seizures from 18 patients with PCE, aged 3-81 months. All had a good prognosis after posterior epileptogenic zone removal. Ictal events were categorized by behavioral, consciousness, autonomic, and sensory features, as well as motor patterns, which included myoclonic, tonic, clonic, unclassified motor seizures, and epileptic spasm. A time-scaled data sheet was developed to record each epileptic event as onset, very early, early, or late manifestation.

RESULTS

Patients had a high seizure frequency with < or =100 attacks/day; one third of them showed a cluster tendency. The mean duration of seizures was 67 s. The most common seizure components were motor manifestations (with myoclonic and tonic seizures), but psychomotor (automotor), hypomotor attacks, and isolated auras also were frequently observed. Clinical seizure spread was frequent; auras and visual sensory signs were difficult to record in this age. Typical phenomena during seizures included behavioral changes, ictal vocalization, smile, flush, head nod, oculomotor features, and late-appearing oral automatisms, whereas hypermotor and secondarily generalized tonic-clonic seizures were not seen.

CONCLUSIONS

Our results suggest that PCE in infants and young children is very heterogeneous but shows important age-related features. Compared with adults, children with PCE have shorter but more frequent seizures; they rarely report aura or visual sensory signs, only sporadically develop hypermotor and secondarily generalized tonic-clonic seizures, whereas ictal smile, flush, head nod, and behavioral change are typical features at this age. Because of frequent subtle ictal phenomena, long-term video-EEG monitoring is a useful diagnostic tool with infants and young children with PCE.