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Individuals with Lennox-Gastaut syndrome (LGS) often do not respond to or become resistant to pharmacologic treatments. Ketogenic diets (KDs) and vagus nerve stimulation (VNS) are nonpharmacologic treatment options for these intractable patients. The classic KD, a high-fat, low-carbohydrate diet with 90% of calories derived from fat, has been used in the treatment of seizures for >90 years. About half of patients with LGS respond to the KD with a >50% reduction in seizures and some patients may achieve a >90% reduction. Vagus nerve stimulation therapy involves a surgically implanted generator that delivers intermittent electrical stimuli to the brain via an electrode wrapped around the left vagus nerve. It is utilized as adjunctive therapy for patients with drug-resistant epilepsy (including patients with LGS) who are not suitable candidates for resective surgery. Similar to the KD, about half of LGS patients respond to VNS therapy, with a >50% reduction in seizures, and the response may improve over time. Both the KD and VNS are options for patients with LGS., (Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.)

Purpose: This study investigated the short-term response to a standardized hormonal therapy protocol for treatment of infantile spasms., Methods: Twenty-seven children with video electroencephalography (EEG)-confirmed infantile spasms received very high dose (8 mg/kg/day, max 60 mg/day) oral prednisolone for 2 weeks. Response (absence of both hypsarrhythmia and spasms) to prednisolone was ascertained by repeat overnight video-EEG. Responders were tapered over 2 weeks and nonresponders were immediately transitioned to high dose (150 IU/m(2)/day) intramuscular adrenocorticotropic hormone (ACTH) for two additional weeks. Response was again determined by overnight video-EEG after ACTH therapy., Key Findings: Sixty-three percent (17/27) of patients responded completely to prednisolone. Subsequently, 40% (4/10) of prednisolone nonresponders exhibited a complete response after an additional 2-week course with ACTH. Among 27 subjects with median follow-up of 13.5 months (interquartile range [IQR] 4.8-25.9), 12% (2/17) of prednisolone responders and 50% (2/4) of ACTH responders experienced a relapse between 2 and 9 months after initial response., Significance: Very high dose prednisolone demonstrated significantly higher efficacy than previously reported for lower doses in prior studies. High dose ACTH may be superior to very high dose prednisolone, and in lieu of a definitive clinical trial, the choice between prednisolone and ACTH for initial treatment of infantile spasms remains controversial., (Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.)

Purpose: To investigate relationships between regional brain metabolites, social communication deficits, and seizure frequency in children and adolescents with cryptogenic epilepsy with complex partial seizures (CPS)., Methods: In 12 children and adolescents with CPS and 23 age- and gender-matched healthy controls, we acquired proton magnetic resonance spectroscopic imaging (MRSI) at 1.5 T and 30 ms echo-time from bilateral inferior frontal and superior temporal gyri, regions associated with social communication deficits. Videotaped speech samples of all the subjects were coded for social communication deficits and parents provided information on seizure frequency., Key Findings: Four MRSI findings emerged in right inferior frontal gyrus. N-acetyl-aspartate (NAA) plus N-acetyl-aspartyl-glutamate (NAAG)--together called "tNAA"--was 11.4% lower in patients with CPS than in controls. Choline-compounds (Cho) were 15.4% lower in CPS than in controls. Within CPS, higher tNAA was associated with more frequent seizures and abnormal social communication., Significance: Localization of findings to right inferior frontal cortex supports the involvement of this area in social communication deficits and may be related to atypical lateralization of expressive language in pediatric epilepsy. Lower levels of tNAA and Cho may indicate local neuronal or glial damage or underpopulation due to excitotoxicity or other causes. The sensitivity of tNAA to seizure frequency suggests effects of ongoing CPS on neuronal and glial function in this brain region., (Wiley Periodicals, Inc. © 2011 International League Against Epilepsy.)

The diagnosis, evaluation, and management of infantile spasms (IS) continue to pose significant challenges to the treating physician. Although an evidence-based practice guideline with full literature review was published in 2004, diversity in IS evaluation and treatment remains and highlights the need for further consensus to optimize outcomes in IS. For this purpose, a working group committed to the diagnosis, treatment, and establishment of a continuum of care for patients with IS and their families—the Infantile Spasms Working Group (ISWG)—was convened. The ISWG participated in a workshop for which the key objectives were to review the state of our understanding of IS, assess the scientific evidence regarding efficacy of currently available therapeutic options, and arrive at a consensus on protocols for diagnostic workup and management of IS that can serve as a guide to help specialists and general pediatricians optimally manage infants with IS. The overall goal of the workshop was to improve IS outcomes by assisting treating physicians with early recognition and diagnosis of IS, initiation of short duration therapy with a first-line treatment, timely electroencephalography (EEG) evaluation of treatment to evaluate effectiveness, and, if indicated, prompt treatment modification. Differences of opinion among ISWG members occurred in areas where data were lacking; however, this article represents a consensus of the U.S. approach to the diagnostic evaluation and treatment of IS.

Purpose: This study compared frontotemporal brain volumes in children with childhood absence epilepsy (CAE) to age- and gender-matched children without epilepsy. It also examined the association of these volumes with seizure, demographic, perinatal, intelligence quotient (IQ), and psychopathology variables., Methods: Twenty-six children with CAE, aged 7.5-11.8 years, and 37 children without epilepsy underwent brain magnetic resonance imaging (MRI) scans at 1.5 Tesla. Tissue was segmented, and total brain, frontal lobe, frontal parcellations, and temporal lobe volumes were computed. All children had IQ testing and structured psychiatric interviews. Parents provided seizure, perinatal, and behavioral information on each child., Results: The CAE group had significantly smaller gray matter volumes of the left orbital frontal gyrus as well as both left and right temporal lobes compared to the age- and gender-matched children without epilepsy. In the CAE group these volumes were related to age, gender, ethnicity, and pregnancy complications but not to seizure, IQ, and psychopathology variables. In the group of children without epilepsy, however, the volumes were related to IQ., Conclusion: These findings suggest that CAE impacts brain development in regions implicated in behavior, cognition, and language. In addition to supporting the cortical focus theory of CAE, these findings also imply that CAE is not a benign disorder.

Purpose: This study examined the severity and range of linguistic impairments in young, intermediate, and adolescent youth with epilepsy and how these deficits were associated with illness effects, nonverbal intelligence, psychopathology, and reading., Methods: Tests of language, intelligence, achievement, and structured psychiatric interviews were administered to 182 epilepsy youth, aged 6.3-8.1, 9.1-11.7, and 13.0-15.2 years, as well as to 102 age- and gender-matched normal children. Parents provided demographic, seizure-related, and behavioral information on their children., Results: Significantly more epilepsy subjects had language scores 1 standard deviation (SD) below average than the age-matched control groups did. The intermediate and adolescent epilepsy groups also had significantly lower mean language scores compared to their matched controls. The older compared to the younger epilepsy groups had more language impairment and a wider range of linguistic deficits. Longer duration of illness, childhood absence epilepsy, psychiatric diagnosis, and socioeconomic status were associated with linguistic deficits in the young group. Prolonged seizures, lower Performance IQ, and minority status predicted low language scores in the intermediate epilepsy group. In the adolescent group, language impairment was associated with poor seizure control, decreased Performance IQ, and lower socioeconomic status. Linguistic and reading deficits were significantly related in each epilepsy group., Conclusions: The age-related increase in linguistic impairment, different profiles of predictors in each age group, and the relationship of linguistic deficits with poor reading skills have important clinical, developmental, theoretical, and academic implications.

Benign epilepsy with centrotemporal spikes (BECTS) is a common disorder in childhood. After a brief overview of BECTS, a review of the data in favor of treatment with anticonvulsant medications is followed by the data indicating that treatment is not indicated. Some children appear to have cognitive consequences from BECTS. The parents and children with BECTS require a full discussion of the pros and cons of treatment, but based on data available at this time, it is concluded that treatment is generally not indicated for most patients. Future research may lead to changes in the recommendations.

Recent findings on the clinical, electroencephalography (EEG), neuroimaging, and surgical outcomes are reviewed comparing patients with Palmini type I (mild) and type II (severe) cortical dysplasia. Resources include peer-reviewed studies on surgically treated patients and a subanalysis of the 2004 International League Against Epilepsy (ILAE) Survey of Pediatric Epilepsy Surgery. These sources were supplemented with data from University of California, Los Angeles (UCLA). Cortical dysplasia is the most frequent histopathologic substrate in children, and the second most common etiology in adult epilepsy surgery patients. Cortical dysplasia patients present with seizures at an earlier age than other surgically treated etiologies, and 33-50% have nonlocalized scalp EEG and normal magnetic resonance imaging (MRI) scans. 2-((18)F)Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is positive in 75-90% of cases. After complete resection, 80% of patients are seizure free compared with 20% with incomplete resections. Compared with type I, patients with type II cortical dysplasia present at younger ages, have higher seizure frequencies, and are extratemporal. Type I dysplasia is found more often in adult patients in the temporal lobe and is often MRI negative. These findings identify characteristics of patients with mild and severe cortical dysplasia that define surgically treated epilepsy syndromes. The authors discuss future challenges to identifying and treating medically refractory epilepsy patients with cortical dysplasia.

Purpose: Vigabatrin used to treat infantile spasms (IS) has been associated with transient magnetic resonance imaging (MRI) abnormalities. We carried out a retrospective review to better characterize the frequency of those abnormalities in IS and in children and adults treated with vigabatrin for refractory complex partial seizures (CPS)., Methods: Medical records and 332 cranial MRIs from 205 infants (aged 16 years) with CPS were re-reviewed. Prespecified MRI abnormalities were defined as any hyperintensity on T(2)-weighted or fluid-attenuated inversion-recovery (FLAIR) sequences with or without diffusion restriction not readily explained by a radiographically well-characterized pathology. MRIs were read by two neuroradiologists blinded to treatment group. The incidence and prevalence of MRI abnormalities associated with vigabatrin were estimated., Results: Among infants with IS, the prevalence of prespecified MRI abnormalities was significantly higher among vigabatrin-treated versus vigabatrin-naive subjects (22% vs. 4%; p < 0.001). Of nine subjects in the prevalence population with at least one subsequent determinate MRI, resolution of MRI abnormalities occurred in six (66.7%)-vigabatrin was discontinued in four. Among adults and children treated with vigabatrin for CPS, there was no statistically significant difference in the incidence or prevalence of prespecified MRI abnormalities between vigabatrin-exposed and vigabatrin-naive subjects., Discussion: Vigabatrin is associated with transient, asymptomatic MRI abnormalities in infants treated for IS. The majority of these MRI abnormalities resolved, even in subjects who remained on vigabatrin therapy.

Unlabelled: Vigabatrin (VGB) is a structural analogue of gamma-aminobutyric acid (GABA) that irreversibly inhibits GABA-transaminase (GABA-T), increasing brain levels of GABA. VGB is under assessment for treatment of infantile spasms (IS) and refractory complex partial seizures (CPS). Response can be rapid with spasm cessation following approximately 2 weeks of therapy. Patients with symptomatic tuberous sclerosis (TS) and other patients have achieved spasm cessation. Comparison with ACTH has been performed. Patients with refractory CPS have responded as well. Adverse effects and structural findings on imaging occur with VGB treatment. T2 hyperintensities within brain have been observed. Psychotic disorders or hallucinations have occurred rarely. A specific adverse effects is associated VGB, with a peripheral visual field defect (VFD) detected in some patients. Prevalence and incidence of the VGB-induced peripheral VFD varied depending on the age of the patient and the extent of exposure to VGB, with 25% to 50% prevalence in adults; the prevalence in children was 15% and retinal defect in infants ranged from 15% to 31%. A bilateral nasal defect may be the first clinical indication and may progress to a concentric, bilateral field defect observed in many affected patients; central visual acuity is almost always preserved. The earliest finding of the first abnormal field examination in adults was after 9 months of treatment; with a mean duration of VGB exposure of 4.8 years. In children, the earliest onset of a first abnormal field examination was after 11 months, with a mean time to onset of 5.5 years. The earliest sustained onset of the VGB-induced retinal defect in infants was 3.1 months., Recommendation: Cognitive, age-appropriate visual field testing is required at baseline and then repeated at intervals in patients who continue therapy. Infants are tested at baseline and at 3-month intervals for the first 18 months of treatment, and then every 6 months thereafter. Adults with CPS are tested at baseline and at 6-month intervals. To select patients who are appropriate for VGB therapy, physicians must consider the benefits of fewer seizures and improved quality of life versus the potential risk of developing a VGBinduced peripheral VFD. Effectiveness of VGB can be detected within 12 weeks of initiating therapy. There appears to be minimal risk associated with a 2- to 3-month trial of VGB to evaluate effectiveness before there is a demonstrable risk of developing the VGB-induced peripheral VFD. If patients do not have a clinical benefit from VGB within 12 weeks of treatment initiation, VGB should be discontinued. If patients have a meaningful reduction in seizures or achieve seizure freedom, then the physician and patient or caregiver must determine if the benefits outweigh the potential risk of developing a peripheral VFD. When VGB is prescribed, the patient must be closely monitored for visual field changes. In cases where spasm or seizure improvement is not achieved within 12 weeks of initiation, VGB should be discontinued. In cases where complete spasm cessation, seizure control, or meaningful improvement is achieved within 12 weeks, continued treatment with VGB is warranted; subsequent periodic monitoring for the peripheral VFD is necessary and should be used to mitigate the risk of the defect. The risk of developing the peripheral VFD with short-term exposure seems to be low, therefore, VGB is an appropriate option for patients with IS or refractory CPS who receive a clinical benefit from its effectiveness, given the clinical consequences of uncontrolled seizures and spasms.

Purpose: Evidence for a poor psychiatric, social, and vocational adult outcome in childhood absence epilepsy (CAE) suggests long-term unmet mental health, social, and vocational needs. This cross-sectional study examined behavioral/emotional, cognitive, and linguistic comorbidities as well as their correlates in children with CAE., Methods: Sixty-nine CAE children aged 9.6 (SD = 2.49) years and 103 age- and gender-matched normal children had semistructured psychiatric interviews, as well as cognitive and linguistic testing. Parents provided demographic, seizure-related, and behavioral information on their children through a semi-structured psychiatric interview and the child behavior checklist (CBCL)., Results: Compared to the normal group, 25% of the CAE children had subtle cognitive deficits, 43% linguistic difficulties, 61% a psychiatric diagnosis, particularly attention deficit hyperactivity disorder (ADHD) and anxiety disorders, and 30% clinically relevant CBCL broad band scores. The most frequent CBCL narrow band factor scores in the clinical/borderline range were attention and somatic complaints, followed by social and thought problems. Duration of illness, seizure frequency, and antiepileptic drug (AED) treatment were related to the severity of the cognitive, linguistic, and psychiatric comorbidities. Only 23% of the CAE subjects had intervention for these problems., Conclusions: The high rate of impaired behavior, emotions, cognition, and language and low intervention rate should alert clinicians to the need for early identification and treatment of children with CAE, particularly those with longer duration of illness, uncontrolled seizures, and AED treatment.

Purpose: The literature suggests that pediatric epilepsy surgery cases that present in status epilepticus (SE) are an unusual occurrence. However, this concept is based on case reports, and the incidence and clinical characteristics of these patients have not been systematically assessed., Methods: The cohort consisted of resective epilepsy surgery cases from 2000 to 2005 (n = 115), and they were classified as presenting with continuous SE requiring medical suppression therapy (n = 6) or intermittent SE (greater than 3 seizures/hour; n = 17). The SE categories were compared with extratemporal surgery patients without SE (non-SE; n = 64) for differences in clinical variables abstracted from the medical record., Results: Continuous SE was noted in 5% and intermittent SE in 15% of resective surgery cases, and all had extratemporal cortical involvement. Compared with continuous SE and non-SE cases, intermittent SE patients were younger at surgery with shorter duration of seizures, and had an increased incidence of active infantile spasms during video scalp EEG monitoring. Compared with non-SE cases, the continuous and intermittent SE groups required a larger number of antiepileptic medications presurgery and 6-months postsurgery, underwent hemispherectomy more frequently, and had an increased incidence of hemimegalencephaly and Rasmussen encephalitis and a lower occurrence of infarct/ischemia and infectious etiologies. Seizure control was over 71% up to 2 years postsurgery, and there were no differences between patient groups. Finally, seizure frequency per hour was greater in continuous SE cases compared with the intermittent SE group., Conclusions: Children presenting with continuous or intermittent SE are not rare in pediatric epilepsy surgery centers, and such cases are more commonly associated with infantile spasms, Rasmussen's syndrome, and hemimegalencephaly pathologies. Seizure outcome after surgery was not altered in pediatric patients because they had presented with continuous or intermittent SE.

Purpose: This study examined affective disorders, anxiety disorders, and suicidality in children with epilepsy and their association with seizure-related, cognitive, linguistic, family history, social competence, and demographic variables., Methods: A structured psychiatric interview, mood self-report scales, as well as cognitive and language testing were administered to 100 children with complex partial seizures (CPSs), 71 children with childhood absence epilepsy (CAE), and 93 normal children, aged 5 to 16 years. Parents provided behavioral information on each child through a structured psychiatric interview and behavior checklist., Results: Significantly more patients had affective and anxiety disorder diagnoses (33%) as well as suicidal ideation (20%) than did the normal group, but none had made a suicide attempt. Anxiety disorder was the most frequent diagnosis among the patients with a diagnosis of affective or anxiety disorders, and combined affective/anxiety and disruptive disorder diagnoses, in those with suicidal ideation. Only 33% received some form of mental health service. Age, verbal IQ, school problems, and seizure type were related to the presence of a diagnosis of affective or anxiety disorder, and duration of illness, to suicidal ideation., Conclusions: These findings together with the high rate of unmet mental health underscore the importance of early detection and treatment of anxiety disorders and suicidal ideation children with CPSs and CAE.

Purpose: This study examined the role of cognition, language, seizure-related, and demographic variables in the psychopathology of children with complex partial seizure disorder (CPS) of average intelligence., Methods: One-hundred one CPS and 102 normal children, aged 5.1 to 16.9 years, had a structured psychiatric interview and cognitive and language testing. Parents provided demographic, perinatal, and seizure-related information, as well as behavioral information through the Child Behavior Checklist (CBCL) and a structured psychiatric interview about the child., Results: Significantly more CPS patients had psychopathology, cognitive deficits, and linguistic deficits than did those in the normal group. Among the patients, Verbal IQ predicted the presence of a psychiatric diagnosis, as well as CBCL scores in the borderline/clinical range. Seizure, linguistic, and demographic variables were unrelated to psychopathology. The cognitive and linguistic deficits of the CPS group, however, were predicted by seizure factors (e.g., prolonged seizures/febrile convulsions; seizure frequency/number of antiepileptic drugs) and demographic factors (e.g., minority status)., Conclusions: Because subtle verbal cognitive deficits predict behavioral disturbances in pediatric CPSs, the study's findings highlight the importance of assessing behavior, cognition, and language in these children. They also underscore the negative impact of prolonged seizures, febrile convulsions, seizure frequency, and antiepileptic drug polytherapy on cognition and language in pediatric CPSs.

Purpose: Acute postoperative seizures (APOSs) are those that occur in the first 7 to 10 days after surgery, and previous studies in temporal lobe epilepsy patients support the notion that APOSs may foretell failure of long-term seizure control. It is unknown whether APOSs also predict seizure outcome or hospital course after hemispherectomy., Methods: Hemispherectomy patients (n = 114) were studied retrospectively and subdivided into the following groups: No APOSs, 1 to 5 APOSs, or >5 APOSs. Intensive care unit (ICU) nursing staff or family members reported and described the APOS events. APOS categories were compared with pre- and postsurgery clinical variables abstracted from the medical record., Results: APOSs occurred in 22.6% of hemispherectomy patients. Compared with the 0 and 1 to 5 APOS groups, patients with >5 APOS showed (a) longer seizure durations before surgery, (b) longer hospitalizations, (c) later oral food intake, (d) more frequent lumbar punctures, (e) worse seizure control at 0.5 and 1 year after surgery, (f) more antiepileptic drug (AED) use at 2 and 5 years after surgery, and (g) higher reoperation rate. No similar differences were found between the 0 and 1 to 5 APOS groups. The day of the APOS, whether the APOS was typical of preoperative seizures, and postsurgery scalp EEG did not predict long-term seizure control. APOS patients in the 1 to 5 and >5 groups had lower pre- and postsurgery Vineland developmental quotients compared with those without an APOS., Conclusions: Hemispherectomy patients with >5 APOSs had a more prolonged and complicated hospital course and worse postsurgery seizure control, more AED use, and higher reoperation rate than did patients with 0 or 1 to 5 APOSs. Thus the number of APOSs was a predictor of postsurgery seizure control and can be used to counsel patients and families about prognosis after hemispherectomy.

The epilepsies of childhood are distinguished by an interesting dichotomy between the benign and catastrophic disorders. Approximately 50% of children outgrow childhood epilepsy as they mature; although the disorder is disruptive for children and families alike, it is not considered a medical disaster. The catastrophic epilepsies of childhood, in contrast, are associated with significant morbidity and mortality. Infantile spasms, Lennox-Gastaut syndrome, and the progressive myoclonic epilepsies are correlated with significant disability and a multiplicity of underlying etiologies. Accurate diagnosis of both the syndrome and the etiology is very important for treatment purposes, as well as for family education, since many of the disorders have a significant genetic component.

Purpose: This study examined the relation between psychiatric diagnosis and mental health services in children with epilepsy and the associated demographic, cognitive, linguistic, behavioral, and seizure-related variables., Methods: The Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS), the Child Behavior Checklist, the Test of Language Development, and the Wechsler Intelligence Scale for Children-Revised (WISC-R) were administered to 114 children, aged 5 to 16 years, with either complex partial seizures (CPS) or primary generalized with absence (PGE, petit mal). A Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) diagnosis and information regarding mental health services were derived from the K-SADS., Results: Although approximately 60% of the subjects had a DSM-IV psychiatric diagnosis, >60% received no mental health treatment. Absence of mental health care was associated with younger age, less parental education, limited number of antiepileptic drugs (AEDs; i.e., one or none), and higher verbal IQ. In addition, children with PGE and a single psychiatric diagnosis were less likely to have a history of mental health treatment., Conclusions: This is the first study to demonstrate unmet mental health need in a large sample of children with CPS and PGE. The study's findings suggest that parents and clinicians should be aware of the mental health needs of children with epilepsy, particularly if they have one or more of the identified risk factors.

Purpose: To assess the efficacy and safety of levetiracetam (LEV) as adjunctive therapy in children with treatment-resistant partial-onset seizures., Methods: Children (aged 6-12 years) with treatment-resistant partial-onset seizures receiving one standard antiepileptic drug (AED) were eligible. After a 4-week baseline period, children received LEV in a 6-week titration phase (target dose, 40 mg/kg/day) followed by an 8-week evaluation phase. Seizure frequency during the evaluation period with individualized LEV doses (20-40 mg/kg/day) were compared with the 4-week baseline seizure frequency. Plasma concentrations of LEV and other AEDs were determined to evaluate potential drug interactions., Results: Twenty-four subjects enrolled and received LEV; 23 entered the evaluation phase, and 22 completed the evaluation phase. Compared with their baseline seizure frequency, 12 (52%) of 23 subjects entering the evaluation phase had their seizure frequency decrease by >50%. Two subjects remained seizure free during the entire evaluation period. LEV did not significantly affect plasma concentrations of any concomitant AED during this study, and no alteration of mean clinical laboratory values was observed. The most commonly reported adverse events were headache, infection, anorexia, and somnolence., Conclusions: This open-label study of adjunctive LEV therapy (at 20-40 mg/kg/day) suggests that LEV is effective, safe, and well tolerated in children ages 6-12 years with treatment-resistant partial-onset seizures. A randomized, placebo-controlled, double-blind trial of LEV adjunctive therapy in children with treatment-resistant partial-onset seizures is needed and ongoing to confirm these open-label findings.

Purpose: The pharmacokinetics of the novel antiepileptic drug (AED) levetiracetam and its major metabolite, ucb L057, were studied in children with partial seizures in a multicenter, open-label, single-dose study., Methods: Twenty-four children (15 boys, nine girls), 6 to 12 years old, received a single dose of levetiracetam (20 mg/kg) as an adjunct to their stable regimen of a single concomitant AED, followed by a 24-h pharmacokinetic evaluation., Results: In children, the half-lives of levetiracetam and its metabolite ucb L057 were 6.0 +/- 1.1 and 8.1 +/-2.7 hours, respectively. The Cmax and area under the curve (AUC) of levetiracetam equated for a 1-mg/kg dose were lower in children (Cmax, norm=1.33 plus minus 0.35 microg/ml; AUCnorm=12.4 +/- 3.5 microg/h/ml) than in adults (Cmax, norm=1.38 +/- 0.05 microg/ml; AUCnorm=11.48 +/- 0.63 microg/h/ml), whereas the renal clearance was higher. The apparent body clearance (1.43 +/- 0.36 ml/min/kg) was approximately 30-40% higher in children than in adults. Levetiracetam was generally well tolerated., Conclusions: On the basis of these data, a daily maintenance dose equivalent to 130-140% of the usual daily adult maintenance dosage (1,000-3,000 mg/day) in two divided doses, on a weight-normalized level (mg/kg/day) is initially recommended. Clinical efficacy trials in children are ongoing with dosages of 20 to 60 mg/kg/day.

Although for most children epilepsy is a relatively benign disorder, for some, epilepsy can be designated as "catastrophic" because the seizures are so difficult to control and because they are strongly associated with mental retardation. The catastrophic childhood epilepsies include uncommon disorders such as early infantile epileptic encephalopathy with suppression burst, severe myoclonic epilepsy of infancy, and epilepsy with myoclonic-astatic seizures. There are other syndromes that are relatively common such as infantile spasms, Lennox-Gastaut syndrome, and Sturge-Weber syndrome. Many children with catastrophic epilepsy have the seizures as a result of underlying brain abnormalities that will inevitably lead to mental retardation whether or not they have seizures. In some patients, however, the mental retardation appears to be caused by the seizures. Developmental plasticity provides children with an opportunity to recover from significant brain injuries. However, the plasticity may also be the cause of the mental retardation. In such patients, control of the seizures may lead to more normal intellectual development. Thus, every effort should be made to control seizures in children with catastrophic epilepsy.

Purpose: Young children with refractory symptomatic epilepsy are at risk for developing neurologic and cognitive disabilities. Stopping the seizures may prevent these disabilities, but it is unclear whether resective surgery is associated with adequate long-term seizure control., Methods: This study determined pre- and postsurgery seizure frequency and antiepileptic drug (AED) use (6 months to 10 years) in children with symptomatic seizures from unilateral cortical dysplasia (CD; n = 64) and non-CD etiologies (i.e., ischemia, infection; n = 71), and compared them with older temporal lobe epilepsy (TLE; n = 31) patients with complex partial seizures., Results: Compared with presurgery, postsurgery seizure frequencies were decreased for CD, non-CD, and TLE patients (p < 0.002), and there were no differences between the three groups from 6 to 24 months after surgery (p > 0.12). At 5 years after surgery, seizure frequencies were greater in CD compared with TLE cases (p = 0.009). Compared with presurgery, the number of AEDs declined after surgery in all three groups (p < 0.002), and positively correlated with seizure frequencies (p = 0.0001)., Conclusions: This study indicates that seizure relief and AED use after resective surgery for symptomatic CD and non-CD etiologies was comparable with complex partial TLE cases up to 2 years after surgery. Furthermore, at 5 years after surgery, CD patients had outcomes better than those before surgery, but worse than TLE cases. In young children, these findings support the concept that early removal of symptomatic pathologic substrates is associated with seizure control and reduced AED use, similar to that noted in older TLE cases up to 2 years after surgery. Seizure control may reduce the risk of developing the seizure-related encephalopathy associated with severe symptomatic early-onset childhood epilepsy.

Unlabelled: The most appropriate time to consider cortical resection to treat medically intractable infantile spasms has not been clearly defined. The risks that need to be reconciled to make this decision are: What is the risk of loss of developmental potential if surgery is delayed too long versus what is the risk of unnecessary surgery if it is done too soon. We propose that, in addition to evaluation of seizures, developmental assessment is a key factor in the surgical decision. The case report illustrates this concept., Case Report: HC had onset of seizures at 9 days of age and developed infantile spasms due to mild right hemimegancephaly. At 19 months, she was having up to 50 seizures/day and was evaluated and approved for right hemispherectomy but surgery was delayed. Despite the seizures, her development had been much better than most patients with hemimegencephaly and infantile spasms. At 25 months her seizure control was much improved but she had several seizures/week. EcoG at the time of surgery did not demonstrate the usual abnormalities so no resection was performed. She has had only 5 seizures in the 2(1/2) year since., Conclusions: (a) Hemimegalencephaly is not always associated with severe mental retardation; (b) normal or near-normal development may, in some cases, indicate the possibility of medical control of seizures as the child grows; (c) a localized developmental brain abnormality in a child with intractable seizures should not necessarily lead to cortical resection; and (d) when a child meets developmental milestones, it may be appropriate to delay surgical intervention.

Purpose: Increased risk of death has been reported in patients with intractable epilepsy (IE) taking nitrazepam (NZP)., Methods: Between January 1983 and March 1994, 302 patients with IE were entered into a NZP compassionate-plea protocol. NZP was discontinued if there was < 50% seizure reduction or significant side effects. In some patients with > 50% reduction, it also was discontinued for lack of sufficient effect. At the end of follow-up for this study, 62 patients remained taking NZP. Patients took NZP from 3 days to 10 years., Results: Twenty-one of 302 patients died after institution of NZP. Fourteen of 21 of these were taking NZP at death, and in five of 21, the NZP had been discontinued. Two patients were excluded from analysis, because it is unclear whether NZP had been discontinued before death. Six other patients were lost from follow-up. Of the 14 deaths with NZP, seven were sudden, six were of pneumonia, and one was of cystinosis. Nine had at least one contributing factor, such as dysphagia, gastroesophageal reflux, or recurrent aspirations. The 294 patients took NZP for a total of 704 patient years (ptyrs), and were discontinued for a total of 856 ptyrs. There were 1.98 deaths/ 100 ptyrs on NZP compared with 0.58 deaths/100 ptyrs without NZP, most of the former being associated with side effects of NZP. Mortality in patients younger than 3.4 years was 3.98 with NZP compared with 0.26 deaths/100 ptyrs without NZP (p = 0.0002). Corresponding figures in patients 3.4 years or older were 0.50 and 0.86 deaths/100 ptyrs, respectively., Conclusions: NZP therapy for epilepsy apparently increases the risk of death, especially in young patients with IE. This should be considered in antiepileptic drug (AED) management decisions.

In November 1996, a panel of pediatric neurologists met to update the consensus statement issued in 1989 by a panel of neurologists and metabolic experts on L-carnitine supplementation in childhood epilepsy. The panelists agreed that intravenous L-carnitine supplementation is clearly indicated for valproate (VPA)-induced hepatotoxicity, overdose, and other acute metabolic crises associated with carnitine deficiency. Oral supplementation is clearly indicated for the primary plasmalemmal carnitine transporter defect. The panelists concurred that oral L-carnitine supplementation is strongly suggested for the following groups as well: patients with certain secondary carnitine-deficiency syndromes, symptomatic VPA-associated hyperammonemia, multiple risk factors for VPA hepatotoxicity, or renal-associated syndromes; infants and young children taking VPA; patients with epilepsy using the ketogenic diet who have hypocarnitinemia; patients receiving dialysis; and premature infants who are receiving total parenteral nutrition. The panel recommended an oral L-carnitine dosage of 100 mg/kg/day, up to a maximum of 2 g/day. Intravenous supplementation for medical emergency situations usually exceeds this recommended dosage.

To analyze the magnitude of the risk factors for infantile spasms, we evaluated the records of 80 children with infantile spasms, 474 children with other types of epilepsy, 2,196 children with febrile seizures, and 262 children with CNS infections. There was a family history of seizures in 13.8% of children with infaNtile spasms, 28.5% of children with other forms of epilepsy, 25.5% of children with febrile seizures, and 5.3% of children with CNS infections. Children with a family history of seizures were 2.82 times more likely to have infantile spasms, 7.05 time more likely to have other epilepsy, and 6.08 time more likely to have febrile seizures than controls (children with CNS infections). However, a family history of seizures increased the risk for infantile spasms only in the cryptogenic group. Children with infantile spasms were significantly more likely to have cerebral palsy, microcephaly, hydrocephaly, CNS malformations, neonatal hypoxia, or neonatal seizures than children with other types of epilepsy, febrile seizures, or CNS infections. There was a modest genetic predisposition to seizures in children with infantile spasms. However, our data suggest a much stronger association with underlying neurologic abnormalities, mainly neonatal seizures, neonatal hypoxia, and CNS malformations.

Pediatric epileptology is very different from adult epileptology. Although some epileptic disorders occur in both children and adults (e.g., localization-related epilepsy with complex partial seizures and primary generalized epilepsy with tonic-clonic seizures), other disorders can be called the catastrophic epilepsies of childhood (e.g., infantile spasms and the Lennox-Gastaut syndrome). They occur, or at least begin, exclusively in childhood and are often associated with mental retardation. Many of these pediatric disorders are notoriously unresponsive to currently available antiepileptic drugs (AEDs). Although there are undoubtedly many reasons for this, one possible explanation is that the methods used to screen potential AEDs use animal models of adult epilepsy. No screening program uses an animal model of seizures that begin during development and lead to functional decline.

Twenty-three infants and children underwent cortical resection (n = 15) or hemispherectomy (n = 8) for intractable infantile spasms. Infantile spasms were present at the time of surgery in 17 of the 23 patients; in six, spasms had evolved to other seizure types during surgical evaluation. Children with a remote history of infantile spasms were excluded from this study. Focal or hemispheric lesions were identified by magnetic resonance imaging in seven children; an additional two showed focal atrophy without a discrete lesion. Positron emission tomography (PET) showed lateralized or localized abnormalities of cerebral glucose utilization in all patients; in 14, PET was the only neuroimaging modality to identify the epileptogenic cortex. When this occurred, neuropathological examination of resected brain tissue typically showed malformative and dysplastic cortical lesions. Focal interictal and/or ictal electrographic abnormalities were present in all patients, and corresponded well with localization from neuroimaging. None of the patients were subjected to chronic invasive electrographic monitoring with intracranial electrodes. At follow-up (range 4-67 months; mean 28.3 months), 15 children were seizure-free, three had 90% seizure control, one had 75% seizure control, and four failed to benefit from surgery with respect to seizure frequency.

Refractory status epilepticus (RSE) is defined as status epilepticus that continues despite aggressive treatment. A 9.8-year-old boy with a past history of daily left focal motor seizures was transferred to University of California at Los Angeles (UCLA) Hospital in pentobarbital coma after 4 days in RSE. The RSE was treated with very high doses of all appropriate antiepileptic drugs (AEDs), alone and in combination. The pentobarbital was titrated to burst suppression on EEG, but whenever pentobarbital was decreased, the seizures recurred. An ictal positron tomography scan of glucose metabolism demonstrated a right frontal area of hypermetabolism corresponding to an epileptic focus on EEG and magnetic resonance lesion. Eight days after the boy was admitted to UCLA, the right frontal focus was surgically removed, with immediate control of the status epilepticus. Whereas before onset of RSE, he had daily focal seizures, the boy has been seizure-free postoperatively for greater than 1 year. Operative treatment should be considered in patients with RSE in whom a focus of seizure onset can be demonstrated and who are reasonably considered surgical candidates.

Although infantile spasms were initially described in 1841, remarkably little progress has been made in understanding the pathophysiology of this "peculiar form of infantile convulsions." Consequently, our ability to treat infantile spasms is limited. Infantile spasms are classified as a "generalized" seizure disorder in the international classification system, which suggests that the underlying brain abnormality causing the seizures also must be diffuse or generalized. As the classification suggests, there are many diffuse, or multifocal, brain disorders related to infantile spasms, e.g., inborn errors of metabolism, hypoxic-ischemic brain injury, and developmental brain defects such as tuberous sclerosis or Aicardi's syndrome. On the other hand, infantile spasms have been reported in which a localized brain abnormality was present, e.g., tumor, stroke, and trauma. On rare occasions, removal of a tumor has resulted in cessation of the generalized infantile spasms. This finding suggests that focal cortical abnormalities can cause infantile spasms and that removing the abnormality can stop the seizures. At University of California, Los Angeles, the Pediatric Epilepsy Surgery Program has developed new approaches to the treatment of infantile spasms. The principal underlying concepts are (a) children with medically refractory infantile spasms may have an area of cortical defect (called the zone of cortical abnormality) that causes the seizures and (b) infantile spasms are usually generalized seizures. Thus, the goal of the surgical assessment is not the identification of the focus of seizure onset but rather the identification of the zone of cortical abnormality.