A Five-Year Follow-Up Study of 66 Epileptics

A follow-up study of 66 patients with epilepsy who had been pursued for about five years from onset of seizures was performed. The patients were selected according to the following criteria: the age of onset of seizures was over 10 years old, and medication started a year from the onset. The results were: controlled 23 (34.8%), improved 17 (25.80/0), unchanged 20 (30.3%), and worsened 6 (9.1%). The duration from the onset to the beginning of medication did not seem to play an important role in the patients whose age of onset was over 10 years old. Seizures had ceased in 19 of 23 of the controlled patients within three years after medication. Thus, the two-year terminal remission rate was 28.8% of the total 66 patients. The number of seizure types was 36 partial seizures in which included 25 secondarily generalized seizures, and 30 generalized seizures. The frequency according to type of seizure, which had been controlled or improved was 41.7% in the partial seizure, and 83.3% in the generalized seizure. The patients with generalized seizure had a better prognosis than those with partial seizures whether they had a past history with respect to suspected brain damage, or not. As to the type of complex seizures in the partial seizure type, the type of impaired consciousness alone frequently developed into secondarily generalized seizure, while a half of the psychomotor seizures did not.     

伴有中央颞区棘波的儿童良性癫(癎)患儿智力水平及智力结构

目的 探讨伴有中央颞区棘波的儿童良件癫(癎)(BECT)患儿的智力水平及智力结构状况,研究各种因素对BECT患儿智力结构的影响.方法 采用中国修订韦氏儿童智力量表(WISC-R)及多重评估法对47例BECT患儿进行韦氏智力测验,语音意识测验和语素意识测验,并与在性别、年龄、文化程度和家庭背景等方面与之相匹配的30名健康儿童作对照比较,同时分析起病年龄、病程、发作频率、发作类型、放电部位和棘慢波指数等临床因素对BECT患儿智力和智力结构的影响.结果 47例BECT患儿平均总智商为104.20±12.34,较对照组(109.45±15.01)略低,但差异无统计学意义,2组之间的操作智商差异亦无统计学意义,仅语言智商(90.67±18.40)与对照组(98.17±13.18)相比显著降低(t=3.431,P<0.05);在语言智商各子项分析中,2组受试者之间"词汇"和"类同"项目差异存在统计学意义(BECT组:5.97±2.95、4.85±3.02,健康对照组:8.51±3.67、6.95±3.07,t=2.365、2.096,均P<0.05);BECT患儿的语音意识得分为12.56±2.34,语素意识得分为22.35±3.25,健康儿童分别为16.78±3.72和24.15±5.28,差异均有统计学意义(t=2.478、2.770,P<0.05);语言智商、"类同"、"词汇"、语音意识及语素意识与非快动眼睡眠(NREM)期棘慢波指数呈负相关(r=-0.305～-0.838,P<0.05),与起病年龄、病程和发作频率无相关性.左侧、右侧和双侧病灶者患儿间智商差异无统计学意义.部分性发作及部分性发作继发全身性发作组之间智商差异亦无统计学意义.结论 BECT患儿有正常的智力,但其智力结构存在不平衡现象,语言功能滞后于健康儿童.棘波指数影响BECT患儿的语言功能,而起病年龄、发作类型和放电部位对语言功能影响不大.     

Autism and epilepsy: a retrospective follow-up study

So-called "idiopathic" autism, which exhibited no major complications before diagnosis is well-known as one of the risk factors for epilepsy. This retrospective follow-up study aimed to clarify the characteristics of epilepsy in the autism; onset of seizure, seizure types, EEG findings and epilepsy outcome and the differences as a group between the autism with epilepsy and those without epilepsy. One hundred thirty individuals with autistic disorder or atypical autism diagnosed in childhood were followed up over 10 years and were evaluated almost every year up to 18-35 years of age. Their medical records related to perinatal conditions, IQ, social maturity scores and several factors of epilepsy were reviewed in October 2005. Thirty-three of the follow-up group (25%) exhibited epileptic seizures. The onset of epilepsy was distributed from 8 to 26 years of age. Two types of seizure were observed; partial seizure with secondarily generalized seizure and generalized seizure. Twenty of the epileptics (61%) showed the partial seizure. Although 18% of the non-epileptic group exhibited epileptic discharges on EEG, 68% of the epileptic group revealed epileptiform EEG findings before the onset of epilepsy. No differences were observed concerning the sex ratio, autistic disorder/atypical autism and past history of febrile seizures between the epileptic and non-epileptic groups. Lower IQ, lower social maturity score and higher frequency of prescribed psychotropics were observed in the epileptic group compared to the non-epileptics. Idiopathic autism was confirmed as the high risk factor for epilepsy. Epileptiform EEG findings predict subsequent onset of epileptic seizures in adolescence. Epilepsy is one of negative factors on cognitive, adaptive and behavioral/emotional outcomes for individuals with autism.     

Early-Childhood Progressive Myoclonus Epilepsy Presenting as Partial Seizures in Dentatorubral-Pallidoluysian Atrophy

Summary: Purpose: We explored the characteristics of epileptic seizures of progressive myoclonus epilepsy (PME) in 2 brothers with dentatorubral-pallidoluysian atrophy (DRPLA).
Methods: We obtained the case history of the siblings and ictal and interictal EEGs. Postmortem examination or demonstration of elongated CAG repeat in the gene for DRPLA was used to confirm the diagnosis.
Results: Two Japanese siblings developed PME characterized by versive or himiclonic seizures with or without secondarily generalized tonic-clonic convulsions. The elder brother regressed mentally and exhibited increasing spasticity after age 1 year. Myoclonus and seizures developed at age 4 years. The younger brother had shown psychomotor retardation before age 4 years, when he began to deteriorate further neurologically as the elder brother had. He also developed myoclonus and seizures at that age. Seizures in both patients remained partial until their deaths at ages 19 and 15 years, respectively. Ictal EEG verified partial onset of seizure evolving to generalized tonic-clonic seizure (GTCS). Interictal EEGs showed multifocal paroxysmal discharges with little or no diffuse paroxysms. Postmortem examination or genetic study confirmed the diagnosis of DRPLA.
Conclusions: Seizures of patients with DRPLA may present as partial seizures in children with early-onset PME.     

Mental retardation subsequent to refractory partial seizures in infancy

Whether seizures are the direct cause of cognitive deterioration in epileptic children is undetermined. This retrospective study aimed to delineate a subgroup of pediatric patients with cognitive deterioration and refractory seizures in the absence of recognized causes for mental retardation. Of the 80 children identified as having mental retardation and refractory seizure disorder, seven (8.7%) had normal cognitive development until at least 1 year of age. Their metabolic status was normal. Five of them suffered repeated frequent partial seizures with onset in the first year of life and two had repeated episodes of status epilepticus. All seven had similar characteristics of early onset partial seizures, six of them had partial seizures secondarily generalized and one had complex partial seizures. The time of peak cognitive deterioration correlated with increases in seizure frequency during that period. Evaluation revealed a well-defined epileptic focus in the absence of neuroimaging abnormality except for hippocampal atrophy in the two children with complex partial seizures and a small vascular malformation in one child. Uncontrolled partial seizures in the first months of life may result in cognitive deterioration.     

Behavior of children with seizures. Comparison with norms and effect of seizure type.

Scores for 112 children aged 6 to 12 years, with well-controlled seizures and of average or higher IQ, were compared for problem behavior with established norms. As assessed on the Conners' Teacher Rating Scale, the group with seizures was comparable to the normative group on two subscales and superior on two others. In contrast, parents of children in the seizure group rated them as significantly worse on all six subscales of the Revised Behavior Problem Checklist. In a larger group of 133 children with seizures, from which this sample was selected, the relationship of age, sex, and seizure type to behavior problems was examined. Subjects with partial seizures were rated as slightly more aggressive and antisocial than those with generalized seizures. Findings were discussed in regard to differences in perception of behavior by parents and teachers and the possible relevance of seizure type to the expression of behavior problems.     

Cognitive skills in children with intractable epilepsy: comparison of surgical and nonsurgical candidates

PURPOSE: To compare neuropsychological performance of two groups of children with intractable epilepsy: those who are surgical candidates, and those who are not. METHODS: Intelligence, verbal memory, visual memory, academic skills, and sustained attention were measured in children aged 6-18 years. The effects of number of antiepileptic drugs (AEDs), seizure frequency, age at seizure onset, and duration of seizure disorder were examined. RESULTS: Both groups had high rates of impairment. Group differences were found only on the verbal memory task. Children who experienced seizures in clusters had higher IQ, reading comprehension, and arithmetic scores. Age at seizure onset and proportion of life with seizures were related to IQ. Performance did not vary with AED monotherapy versus polytherapy. CONCLUSIONS: Few differences exist in cognitive performance between children with intractable seizures who are and those who are not surgical candidates. These findings suggest that children who are not surgical candidates can serve as good controls in studies on cognitive outcome of surgery.     

Computed tomography and childhood seizure disorders

Computerized tomography (CT) was performed on 256 children with seizure disorders. The incidence of abnormal scans was closely related to seizure type, and permitted separation of patients into a low-yield and a high-yield group. Low-yield groups included children with idiopathic generalized seizures, children in whom both the neurologic examination and electroencephalogram (EEG) were normal, and children with a generalized seizure of unknown etiology in whom the neurologic examination and the EEG were normal. The high-yield groups included children with partial seizures with elementary symptomatology, partial seizures with complex symptomatology, generalized seizures with known etiology, neonates with seizures, and children whose seizures began as neonates. The overall incidence of abnormalities in the entire group was 33 percent. An abnormal neurologic examination increased the incidence of abnormal CT scans to 64 percent. EEGs were abnormal in 65 percent of the children, but only focal slowing resulted in a significant increase in the incidence of abnormal CT scans. Seven children (2.7 percent) had intracranial abnormalities requiring surgery. If the neurologic examination and EEG were normal, the yield of abnormal CT scans was only 5 percent of the total.     

Generalized‐onset seizures with secondary focal evolution

The international seizure classification recognizes that partial‐onset seizures can become secondarily generalized, but generalized‐onset seizures are expected to remain generalized. We report six patients who had recorded seizures with generalized onset, but subsequent evolution into a focal discharge. The clinical seizure onset was generalized absence or myoclonic, and the most common subsequent clinical pattern was prolonged behavioral arrest with mild automatisms, and then postictal confusion. The ictal discharge started with generalized spike‐and‐wave activity and then acquired a focal predominance. Interictal epileptiform activity was generalized. There were no focal magnetic resonance imaging abnormalities. Four patients were misdiagnosed with complex partial seizures. All patients were initially refractory, but three became seizure‐free and three improved after treatment with antiepileptic medications appropriate for absence or myoclonic seizures. Generalized‐onset seizures that acquire focal features are easily misdiagnosed as complex partial. These seizures have a more favorable response to medications effective against generalized absence and myoclonic seizures.     

Relationships within the idiopathic generalized epilepsies

The relationships between the various epileptic syndromes, which comprise the idiopathic generalized epilepsies that commence after infancy, were explored in 451 patients by comparing the incidences of various clinical and electroencephalographic features in subsets of the patients, determined primarily by their clinical patterns of seizure phenomena (absences, myoclonic and generalized tonic-clonic seizures), and secondarily by their ages at the onset of their seizures. The approach showed a bimodal distribution of ages of onset in the absence epilepsy group only. More subjects whose absences had begun under 10 years of age experienced very frequent episodes (52.0% vs 26.9%) and fewer experienced generalized tonic-clonic seizures (44.0% vs 71.2%). These differences were consistent with the distinction made in the International League Against Epilepsy's Classification between childhood and adolescent onset absence epilepsy. There were no unambiguous age of onset related differences in the incidences of the features studied within each of the myoclonic seizure and the generalized tonic-clonic seizure only groups, although there were differences in the incidences of the features between the two groups. Thus the idiopathic generalized epilepsies studied appeared to comprise a number of discrete entities rather than a smooth continuum of age of onset related epileptic phenomena.     

The diversity of seizures related to alcohol use. A study of consecutive patients

The aim of this study was to investigate the influence of hazardous alcohol drinking on the occurrence of epileptic seizures, the semiology of such seizures, and the extent of the problem. A consecutive sample of 142 acute seizure patients (78 male and 64 female, mean age 46 (16-79) years) was studied. Control groups were 185 consecutive sciatica patients and 254 healthy individuals. Subjects with a hazardous alcohol drinking level were identified by a score >8 in the Alcohol Use Disorders Identification Test (AUDIT). Seizures in AUDIT-positive individuals occurring within 72 h of the last drink were considered to be related to alcohol withdrawal. Generalized or partial onset seizures were classified on the basis of history, electroencephalographic (EEG) and neuroradiological findings. Thirty-five percent of seizure patients were AUDIT-positive, whereas conversely 27% were abstainers. Two-thirds of AUDIT-positive seizure patients met the criteria for withdrawal seizures. Indications of partial onset seizures were found in 25 (51%) of AUDIT-positive patients, all secondarily generalized seizures. Sixty percent of generalized onset seizure patients were AUDIT-positive. In conclusion, seizure patients included significantly more AUDIT-positive subjects, as well as abstainers, than healthy Norwegian controls and consecutive sciatica patients from our hospital. Partial onset seizures are more frequent among hazardous drinkers than hitherto recognized. A generalized onset seizure in adults warrants a high suspicion of alcohol as a provoking factor. Routine screening of acute seizure admissions with the Alcohol Use Disorders Identification Test is recommended.     

The effect of seizure type and medication on cognitive and behavioral functioning in children with idiopathic epilepsy

Antiepileptic drugs have been reported to have a variety of adverse effects on behavior and performance in children with epilepsy. Previous studies investigating these side effects, however, have not controlled for the baseline status of the child (e.g. underlying neurological condition, seizure type, socioeconomic status, family variables), making it difficult to determine whether changes in function are attributable to the use of medication. We investigated the cognitive and behavioral profiles of 43 children, aged from 4 to 16 years, with new onset, idiopathic seizures. Twenty-six of these children participated in a 6-month follow-up study, and 12 in a 12-month follow-up study, investigating the effects of antiepileptic medications on psychological functioning. The children were of average intelligence (mean 1Q108) and had not previously been treated with antiepileptic medication. Children were classified as having either generalized convulsive, generalized non-convulsive (absence), simple partial, or complex partial seizures. Prior to the initiation of treatment, children with partial seizures were found to perform better than children with generalized seizures on measures of cognitive functioning. Children with convulsive seizures obtained significantly higher cognitive scores than those with non-convulsive seizures. Children with generalized non-convulsive seizures had lower cognitive scores than subjects with other types of seizure. No differences were found between groups at baseline prior to the initiation of antiepileptic medications. Analysis of subjects' performance after 6 and 12 months of antiepileptic therapy showed no significant deterioration attributable to medication. The differences in cognitive performance of the four seizure groups at baseline were not apparent at the time of follow-up. These results indicate that intrinsic and environmental variables may play a more significant role in predisposing certain children to cognitive and learning problems than do antiepileptic medications.     

Dynamic changes of ictal high-frequency oscillations in neocortical epilepsy: using multiple band frequency analysis

PURPOSE: To characterize the spatial and temporal course of ictal high-frequency oscillations (HFOs) recorded by subdural EEG in children with intractable neocortical epilepsy. METHODS: We retrospectively studied nine children (four girls, five boys; 4-17 yr) who presented with intractable extrahippocampal localization-related epilepsy and who underwent extraoperative video subdural EEG (1000 Hz sampling rate) and cortical resection. We performed multiple band frequency analysis (MBFA) to evaluate the frequency, time course, and distribution of ictal HFOs. We compared ictal HFO changes before and after clinical onset and postsurgical seizure outcomes. RESULTS: Seventy-eight of 79 seizures showed HFOs. We observed wide-band HFOs ( approximately 250 Hz, approximately 120 electrodes) in six patients either with partial seizures alone (three patients) or with epileptic spasms (three patients). Three patients with partial seizures that secondarily generalized had wide-band HFOs ( approximately 170 Hz) before clinical onset and sustained narrow-band HFOs (60-164 Hz) with electrodecremental events after clinical onset ( approximately 28 electrodes). In four postoperatively seizure-free patients, more electrodes recorded higher-frequency HFOs inside the resection area than outside before and after clinical seizure onset. In five patients with residual seizures, electrodes recorded more HFOs that were of higher or equal frequency outside the surgical area than inside after clinical onset. CONCLUSION: For partial seizures alone and epileptic spasms, more electrodes recorded only wide-band HFOs; for partial seizures that secondarily generalized, fewer electrodes recorded wide-band HFOs, but in these seizures electrodes also recorded subsequent sustained narrow-band ictal HFOs. Resection of those brain regions having electrodes with ictal, higher HFOs resulted in postsurgical seizure-free outcomes.     

Effect of early versus late onset of major motor epilepsy on cognitive-intellectual performance: further considerations.

Two groups of adult patients, one with early (0-5 years), the other with late (10-15 years) age of seizure onset, were compared on 14 variables derived from the Wechsler Adult Intelligence Scale (WAIS) and Halstead's neuropsychological measures. The groups were matched for duration of the disorder and seizure frequency, and all subjects (Ss) had unequivocal histories of major motor seizures. The group with early age of onset obtained significantly lower WAIS, Verbal IQ, Performance IQ, and Full Scale IQ values than the group with late age of onset. No significant intergroup differences were obtained on Halstead's measures, although the performances of both groups were impaired vis-a-vis non-neurological control expectancy. The results suggest that early onset age, as operationally defined in this study, has a specifc differential influence which is restricted to psychometric intellectual functions as measured by the WAIS in groups matched for seizure duration and seizure frequency.     

The clinical spectrum of epilepsy in children and adults with hypothalamic hamartoma

PURPOSE: Hamartomas of the hypothalamus (HH) cause an uncommon and unusual epilepsy syndrome. The condition is recognized to affect children, but the presentation in adults is not well understood. We present 19 children and adult patients with HH, including three patients whose epilepsy began in adult life. The patterns of clinical presentation, evolution of the epilepsy from childhood to adult life, and electroclinical diagnostic features are presented. METHODS: Nineteen patients, both children and adults with HH and epilepsy, were evaluated clinically, with EEG, video-EEG, and magnetic resonance imaging (MRI) scanning. Seven patients underwent surgical resection of the hamartoma. Stereotactic thermocoagulation of the hamartoma was performed in two patients. RESULTS: Gelastic seizures occurred at onset of epilepsy in 15 of 16 early-onset cases. Subsequently, multiple seizures types occurred, which then evolved to mainly partial epilepsy with tonic or complex partial seizures (five of eight adults), or became entrenched symptomatic generalized epilepsy with atypical absences, drop attacks, and secondarily generalized seizures, and cognitive impairment (three of eight adults). In the adult-onset patients, gelastic seizures were not prominent, the epilepsy was milder, and they functioned normally. Stereotactic thermocoagulation of the hamartoma resulted in improvement in seizure control in two patients. CONCLUSIONS: Gelastic seizures are not a prominent feature of epilepsy in adult patients with HH. The epilepsy associated with HH, although severe at onset, can evolve into a milder syndrome in later life. For less severely affected patients, minimally invasive alternatives to the traditionally difficult open surgical treatment should be considered.     

Characteristics of Seizures in a Population-Based Series of Mentally Retarded Children with Active Epilepsy

Summary: Purpose: The characteristics of seizures were analysed in a population-based study of active epilepsy in 6-to 13-year-old mentally retarded children. Methods: The search procedure included diagnostic registers, EEG registers, and registers of the Education of the Subnormal. Medical files were scrutinized, and clinical examinations and interviews with parents or caretakers or both were performed. Results: The median age of seizure onset was 1·3 years, 3·1 for children with mild retardation and 0·8 for children with severe retardation. Among the 98 children identified, current seizure groups were partial in 20, generalized in 59, and mixed in 19. The prevailing seizure types were tonic-clonic, myoclonic, atypical absences, and partial complex seizures, present in 42, 33, 23, and 23 children, respectively. A total of 46 children had more than one seizure type. Seizures every day/week occurred in 44 children. There was a constancy between seizure type at onset and later seizure type. Neonatal seizures (n = 25), infantile spasms (n = 12), and status epilepticus (n = 37) occurred independent of one another. Prognostic factors for poor neurologic outcome were early onset of epilepsy, infantile spasms as onset type, and prior neonatal seizures. Children with only partial seizures less frequently had severe mental retardation, cerebral palsy, and visual impairment than those with only generalized seizures. Conclusions: Epilepsies in children with mental retardation are characterized by severe seizure manifestations. The brain damage giving rise to mental retardation and epilepsy is probably the main factor in terms of seizure outcome.     

Operational classification of seizure types by the International League Against Epilepsy: Position Paper of the ILAE Commission for Classification and Terminology

The International League Against Epilepsy (ILAE) presents a revised operational classification of seizure types. The purpose of such a revision is to recognize that some seizure types can have either a focal or generalized onset, to allow classification when the onset is unobserved, to include some missing seizure types, and to adopt more transparent names. Because current knowledge is insufficient to form a scientifically based classification, the 2017 Classification is operational (practical) and based on the 1981 Classification, extended in 2010. Changes include the following: (1) “partial” becomes “focal”; (2) awareness is used as a classifier of focal seizures; (3) the terms dyscognitive, simple partial, complex partial, psychic, and secondarily generalized are eliminated; (4) new focal seizure types include automatisms, behavior arrest, hyperkinetic, autonomic, cognitive, and emotional; (5) atonic, clonic, epileptic spasms, myoclonic, and tonic seizures can be of either focal or generalized onset; (6) focal to bilateral tonic–clonic seizure replaces secondarily generalized seizure; (7) new generalized seizure types are absence with eyelid myoclonia, myoclonic absence, myoclonic–atonic, myoclonic–tonic–clonic; and (8) seizures of unknown onset may have features that can still be classified. The new classification does not represent a fundamental change, but allows greater flexibility and transparency in naming seizure types.     

Operationale Klassifikation der Anfallsformen durch die Internationale Liga gegen Epilepsie: Positionspapier der ILAE-Klassifikations- und Terminologiekommission

The International League Against Epilepsy (ILAE) presents a revised operational classification of seizure types. The purpose of this revision is to recognize that some seizure types can have either a focal or generalized onset, to enable a classification when the onset is unobserved, to include some missing seizure types and to implement a more transparent and understandable nomenclature. Because current knowledge is insufficient to form a scientifically based classification, the 2017 classification is operational (practical) and based on the 1981 classification with the amendments from 2010. The changes include the following: (1) “partial” becomes “focal”; (2) awareness (disturbance of consciousness) is used as a classification criterion of focal seizures; (3) the terms dyscognitive, simple partial, complex partial, psychic and secondarily generalized are eliminated, (4) new focal seizure types include automatisms, behavior arrest, hyperkinetic, autonomic, cognitive, and emotional, (5) epileptic spasms as well as atonic, clonic, myoclonic and tonic seizures can have a focal or generalized onset, (6) focal (seizure with progression) to (a) bilateral tonic-clonic seizure replaces secondarily generalized seizure, (7) new generalized seizure types are absence with eyelid myoclonia, myoclonic absence, myoclonic-atonic, myoclonic-tonic-clonic seizures and (8) seizures of unknown onset may have features that can still be classified. The new classification does not represent a fundamental change but enables greater flexibility and transparency in naming seizure types.     

Semistructured Interview for Seizure Classification: Agreement with Physicians'' Diagnoses

A semi-structured interview was developed for classification of seizures in accordance with the 1981 International League Against Epilepsy (ILAE) criteria. The interview was administered over the telephone by trained lay interviewers. Interview-based diagnoses for 50 patients were compared with independent diagnoses by neurologists who also use the ILAE system for seizure classification. Interview diagnoses agreed with those of physicians for broad seizure-type classifications (i.e., partial vs. generalized onset) in 88% of patients and for detailed combinations of seizure type in 64% of patients. Nonchance agreement between the two sources, assessed by the kappa statistic, was excellent for any partial onset (kappa = 0.83), secondarily generalized (kappa = 0.81), and primary generalized tonic-clonic (kappa = 0.76) seizures. Agreement was fair to good for any generalized onset (kappa = 0.70), simple partial (kappa = 0.56), complex partial (kappa = 0.54), and generalized nonconvulsive (kappa = 0.56) seizures. Sensitivity ranged from 0.60 to 1.0 for partial onset seizures, and from 0.43 to 0.67 for generalized onset seizures. Specificity ranged from 0.60 to 0.87 for partial onset seizures, and was 1.0 for generalized onset seizures. Positive predictive value was 0.95 for any partial onset and 1.0 for any generalized onset seizure. These results suggest that this interview can produce accurate diagnoses of major seizure categories. Use of this instrument for clinical epilepsy research should facilitate conduct of large studies at a significant saving of both time and money.     

Some factors influencing the likelihood of partial onset seizures becoming secondarily generalized

We explored the influences of gender and age of insult on the likelihood of partial seizures becoming secondarily generalized in a group of patients with medically refractory partial seizures of temporal lobe origin. The data suggest that the time period during which damage can lead to an increased frequency of secondarily generalized seizures differs between the sexes. Females show a relatively short window of susceptibility, which seems to be concentrated in the first year of life. The length of this window is longer for males and extends through childhood. Furthermore, laterality of seizure origin has little impact on seizure type.