Levetiracetam reduces frequency and duration of epileptic activity in patients with refractory primary generalized epilepsy.

PURPOSE: Levetiracetam (LEV) is a new antiepileptic drug highly effective as add-on treatment in refractory partial epilepsies. In animal models, LEV is effective against absence seizures. A limited number of case reports and series indicate that LEV reduces seizure frequency in patients with generalized epilepsies. METHOD: We evaluated with continuous EEG eight adult patients with idiopathic generalized epilepsy (IGE). All patients were refractory to the conventional therapy for IGE. Four patients received LEV as add-on therapy, and in four, a conversion to LEV monotherapy was undergone. Epileptic activity was analyzed in order to determine spike-wave density as well as median and maximal duration of spike-wave discharges. Each patient underwent a 24h EEG baseline monitoring before starting LEV therapy. A second 24h EEG examination was performed after a mean follow-up period of 136 days. RESULTS: Spike-wave density (spikes/h) was reduced by 78% after LEV administration. Median spike-wave duration decreased by 72% (p < 0.05). Maximal spike-wave duration was 6s before, and 1.5s after LEV with a percentage change of 81% (p < 0.05). The four patients on LEV monotherapy evidenced also a considerably improvement after conversion. CONCLUSIONS: This study showed that LEV produces a consistent long-term reduction of interictal epileptic activity in patients with refractory IGE. The reduction in the spike-wave activity additionally correlated with a clinically relevant antiepileptic effect. Our results support the concept that LEV could be an alternative therapy in primary generalized epilepsies.     

Tonic status epilepticus in patients with idiopathic generalized epilepsy.

RATIONALE: Tonic status epilepticus (TSE) in patients with idiopathic generalized epilepsy (IGE) is not well recognized. The objective of this study is to report episodes of TSE in patients with IGE. METHODS: We retrospectively reviewed the clinical and EEG evaluation of three IGE patients who presented TSE. RESULTS: The three patients had mainly clinical features of IGE, but had developed, in addition, focal discharges, diffuse EEG abnormalities and some focal or diffuse neuropsychological dysfunction. The tonic attacks eventually responded to treatment, but were not completely controlled in any of the patients. DISCUSSION: The continuum between IGE and secondary generalized epilepsy is demonstrated in these patients. Most of their clinical and EEG features are however, in keeping with an idiopathic generalized epileptic process with additional focal and diffuse components. Recognition of the significance of TSE in such patients has important therapeutic and prognostic implications. [Published with video sequences].     

Learning Disabilities in Epilepsy: Neurophysiological Aspects

Summary: Subclinical generalized spike-wave discharges are often accompanied by transitory cognitive impairment, demonstrable by psychological testing during EEG recording. Transitory cognitive impairment is demonstrated most readily by difficult tasks and during generalized regular spike-wave bursts lasting for more than 3 s, but can also be found during briefer and even focal discharges. That this is not simply a consequence of global inattention is shown by the fact that focal discharges exhibit some specificity: left-sided focal spiking is more likely to produce errors on verbal tasks, for instance, whereas right-sided discharges are more often accompanied by impairment in handling nonverbal material. Both learning difficulties in general and specific abnormal patterns of cognitive functioning are well documented in children with epilepsy and are most pronounced in those with frequent interictal discharges. However, there is now evidence that intermittent cognitive impairment due to the discharges themselves contributes significantly to such neurophysiological abnormalities. The significance of transitory cognitive impairment accompanying subclinical EEG discharges for everyday functioning is uncertain, but there is experimental evidence that subclinical discharges may be accompanied by disruption of educational skills in children or by impairment of driving performance in motorists. In some individuals, suppression of discharges by antiepileptic drugs has demonstrably improved psychological function, but further work is required to determine the indications for such treatment     

EEG in adult-onset idiopathic generalized epilepsy

PURPOSE: It remains controversial whether adult-onset idiopathic generalized epilepsy (IGE) is a distinct syndrome or a continuum among IGE syndromes. EEG is the only known biologic marker of IGE and helps differentiate many of its classic subsyndromes. In this study, we looked for the differences in the EEG findings of IGE of classic adolescent onset versus adult onset that may suggest syndromic heterogeneity. METHODS: Seventy-six patients (47 adolescent-onset IGE, 29 adult-onset IGE) with a clinical and EEG diagnosis of IGE were included. We defined IGE with age at onset of 11-20 years as adolescent-onset IGE and age at onset of 20 years or after as adult-onset IGE. Patients with first-decade onset of seizures, delayed EEGs, and no EEG available for review were excluded. The first EEG was performed within 24 h of the seizure, and if negative, a sleep-deprived EEG was done. All EEGs were reviewed in detail with respect to the background activity and the generalized spike-wave (GSW) characteristic. RESULTS: EEGs (87; 56 adolescent-onset IGE, 31 adult-onset IGE) were systematically reviewed. Background was normal in all patients. The morphology, amplitude, duration, frequency, occurrence, or activation of the GSW pattern did not differ between these two groups. CONCLUSIONS: No differences of EEG features were found between the classic adolescent-onset and the adult-onset IGE. This supports the hypothesis that they share common biologic determinants and exist along a life-long age spectrum of classic IGE.     

Seizure characterization and electroencephalographic features in Glut-1 deficiency syndrome

PURPOSE: To characterize seizure types and electroencephalographic features of glucose transporter type 1 deficiency syndrome (Glut-1 DS). METHODS: Twenty children with clinical and laboratory features of Glut-1 DS were evaluated. Age at seizure diagnosis, seizure classification, and response to treatment were determined by chart review. Thirty-two continuous 24-h EEG monitoring sessions and reports of 42 routine EEG studies were assessed. RESULTS: Age at seizure diagnosis was between 4 weeks and 18 months (mean, 5 months). Seizure types were generalized tonic or clonic (14), absence (10), partial (nine), myoclonic (six), or astatic (four). During 24-h EEGs, background activity showed generalized 2.5- to 4-Hz spike-wave discharges (41%), generalized slowing or attenuation (34%), no abnormalities (34%), focal epileptiform discharges (13%), or focal slowing or attenuation (9%). No seizures were captured during 69% of the studies; the remainder had absence (19%), myoclonic (9%), or partial seizures (3%). On evaluation of routine and 24-h EEG studies, focal epileptiform discharges (24%) and slowing (11%) were more frequent in ages 0-24 months. In older children (2-8 years), generalized epileptiform discharges (37.5%) and slowing (21%) were more common. CONCLUSIONS: In all ages, a normal interictal EEG was the most common EEG finding. When abnormalities occurred, focal slowing or epileptiform discharges were more prevalent in the infant. In older children (2 years or older), a generalized 2.5- to 4-Hz spike-wave pattern emerged. Seizure types observed included, absence, myoclonic, partial, and astatic.     

Diffuse Spike-Wave Status of 9-Year Duration Without Behavioral Change or Intellectual Decline

Summary Continuous, generalized 2.5 to 3.5-Hz spikewave (SW) discharges were evident in an EEG performed 13 h after a first seizure associated with a viral illness, in an 8-year-old girl. On eye opening, the EEG abnormality was suppressed and replaced by delta activity and brief spike-wave paroxysms. No alteration in consciousness and seizures or behavioral abnormalities accompanied the EEG findings. Based on the EEG, she was diagnosed as having "diffuse electrical status," the rare EEG phenomenon that occurs during wakefulness without associated behavioral changes. Although the child was completely normal clinically, the EEG findings persisted during a 9-year-follow-up period. Ethosuximide (ESM) 1 gr daily resulted in temporary disappearance of the bioelectrical status. During the last 2 years without medication the EEG finding tended to be restricted to the posterior regions.     

Jeavons syndrome existing as occipital cortex initiating generalized epilepsy

Purpose: Jeavons syndrome (JS) is one of the underreported epileptic syndromes characterized by eyelid myoclonia (EM), eye closure–induced seizures/electroencephalography (EEG) paroxysms, and photosensitivity. JS has been proposed as idiopathic generalized epilepsy (IGE) because of normal posterior dominant background activity and paroxysmal generalized ictal epileptiform discharges (EDs). However, we noticed subtle occipital EDs preceding EM and interictal posterior EDs using digital video‐EEG. We studied clinical and EEG findings in JS to determine the specific occipital lobe relation to this “eye closure–induced” reflex IGE. Methods: We identified 12 children who met the diagnostic criteria of JS from January 2004 to April 2009 at the Hospital for Sick Children, Toronto, Canada. All patients had EM captured by video‐EEG. We reviewed and described ictal EEG patterns, interictal abnormalities, and demographics, clinical, and neuroimaging findings. Key Findings: All patients but one were female (92%). Age at seizure onset ranged from 1.5 to 9 years, with a mean age of 4.9 years. Six patients (50%) were previously diagnosed as having absence epilepsy and 10 patients were on antiepileptic medications. All 12 patients had normal posterior dominant alpha rhythm, reactive to eye opening and closure. Spiky posterior alpha activity was noted with sustained eye closure in six patients (50%). Interictally, there were generalized EDs found in 10 patients (83%); four of them also had focal interictal EDs over the posterior head region. Eleven patients (92%) had evidence of focal posterior ictal EDs. EM and/or paroxysmal EDs were induced by photic stimulation in 9 (75%) and hyperventilation in 7 (58%). Significance: We observed two neurophysiologic findings in JS: (1) focal interictal EDs from posterior head region; and (2) predominant focal posterior ictal EDs preceding generalized EDs. Further clinical observations of seizures induced by eye closure, photic stimulation, and hyperventilation along with EEG paroxysms would raise the possibility of the occipital cortex initiating generalized epilepsy network involving the brainstem, and thalamocortical and transcortical pathways in JS.     

EEG features in idiopathic generalized epilepsy: clues to diagnosis

PURPOSE: To investigate the EEG profile and its contribution for diagnosis and management in a group of patients with a clinical diagnosis of idiopathic generalized epilepsy (IGE) who were referred to a tertiary hospital. METHODS: We retrospectively studied clinical and EEG features of 180 consecutive patients with IGE. Eighty patients were diagnosed with juvenile myoclonic epilepsy (JME), 35 had absence epilepsy (AE), 13 had generalized tonic-clonic seizures on awakening (GTCS-A), 28 had generalized tonic-clonic seizures only (TCS), and 24 had adult-onset idiopathic generalized epilepsy (AIGE). The EEGs were classified in typical (synchronous generalized spike or polyspikes-and-wave discharges with normal background), atypical (with clear focalities or asymmetries), and normal. RESULTS: The 493 EEG exams were analyzed. The first EEG was normal in 45% of the 180 patients, and only 33% had typical abnormalities. AE had a higher proportion of typical examinations and needed fewer sequential examinations to register a typical abnormality compared with the other groups. By contrast, the serial EEG profile of TCS and AIGE showed a higher proportion of normal and atypical EEG findings. CONCLUSIONS: These findings support previous recommendations that IGE patients should be treated with appropriate therapy based on clinical history. Waiting for a typical abnormal EEG pattern can generate an unacceptable delay in the correct diagnosis and treatment of these patients. In patients with long-term epilepsy, the diagnosis may be difficult. Furthermore, serial EEGs can help to elucidate the syndromic diagnosis, especially in patients with TCS and AIGE.     

EEG criteria predictive of complicated evolution in idiopathic rolandic epilepsy

BACKGROUND: Although so-called "benign" epilepsy with centrotemporal spikes (BECTS) always has an excellent prognosis with regard to seizure remission, behavioral problems and cognitive dysfunctions may sometimes develop in its course. To search for clinical or EEG markers allowing early detection of patients prone to such complications, the authors conducted a prospective study in a cohort of unselected patients with BECTS. METHODS: In 35 children with BECTS, academic, familial, neurologic, neuropsychological, and wake and sleep EEG evaluations were repeated every 6 to 12 months from the beginning of the seizure disorder up to complete recovery. RESULTS: In 25 of 35 patients (72%), behavioral and intellectual functioning remained unimpaired. In 10 of 35 patients (28%), educational performance and familial maladjustment occurred. These sociofamilial problems were correlated with impulsivity, learning difficulties, attention disorders, and minor (7/35 cases, 20%) or serious (3/35 cases, 8%) auditory-verbal or visual-spatial deficits. Worsening phases started 2 to 36 months after onset and persisted for 9 to 39 months. Occurrence of atypical evolutions was significantly correlated with five qualitative and one quantitative interictal EEG pattern: intermittent slow-wave focus, multiple asynchronous spike-wave foci, long spike-wave clusters, generalized 3-c/s "absence-like" spike-wave discharges, conjunction of interictal paroxysms with negative or positive myoclonia, and abundance of interictal abnormalities during wakefulness and sleep. Clinical deterioration was not linked with seizure characteristics or treatment. CONCLUSION: Different combinations of at least three of six distinctive interictal EEG patterns and their long-lasting (> or =6-month) persistence seem to be the hallmarks of patients with BECTS at risk for neuropsychological impairments.     

Electroencephalographic studies of family members of patients with juvenile myoclonic epilepsy]

Juvenile myoclonic epilepsy (JME) is a common idiopathic generalized epilepsy (IGE); it has a clinical and probably a strong genetic relation to the other IGE forms. Generalized spike/polyspike-wave discharges (SW/PSW) are typical of all IGEs. The aim of our study was to determine the incidence of epilepsy and SW/PSW in EEG of family members of 12 JME patients. 35 first degree relatives aged over 15 years were examined. 40 min EEG with 5 min HV were recorded. IGE was diagnosed in 3 (8.6%) persons: JME in 2 and childhood absence epilepsy (CAE) in 1 person. Six more relatives (17.1%) had typical SW/PSW traits in EEG. Thus the IGE features were found in 9 (25.7%) individuals--members of 7 out of 12 families (58%). EEG of 7 other relatives (20%) revealed non-specific episodic diffuse or focal abnormalities. The above results reveal higher incidence of different kinds of ICEs and typical EEG traits in families of JME patients. This findings confirm familial susceptibility to IGE and may be helpful in genetical counselling.     

Genetic models of absence epilepsy, with emphasis on the WAG/Rij strain of rats.

In this review, the main characteristics of genetic models of absence epilepsy, in particular with respect to WAG/Rij rats, are presented. Genetic models are important and relevant, since evidence exists that these models mimic spontaneously occurring human epilepsy more than models in which epilepsy is artificially induced. Genetic models can be divided into models in which seizures are elicited and into those in which epilepsy appears without any sensory stimulation. The majority of genetic models show that absence type of epilepsy; during the last few years, we and others have noticed that rats of various strains exhibit spontaneously occurring spike-wave discharges in the EEG. Among the strains highly affected is the WAG/Rij strain, which is a fully inbred strain. Individuals are homozygous and because of this property, genetic studies are meaningful. Electrophysiological studies have indicated that abnormal discharges in the cortical EEG are generalized and that the hippocampus is not involved. Parts of the thalamus, together with the thalamic reticular nucleus, apparently act as a pacemaker for the abnormal discharges. There is a circadian modulation in the number of spike-wave discharges. Discharges mainly occur during intermediate levels of vigilance such as passive wakefulness and light slow-wave sleep and at transitions of sleep states. Pharmacological studies with clinically effective antiepileptic drugs have shown a close agreement in seizure response between man and rat. Studies with new compounds have emphasized the role of the GABAergic and glutamatergic system in this type of epilepsy. Particularly striking is the role of the GABAergic system. GABA agonists enhance and GABA antagonists reduce the occurrence of spike-wave discharges, which deviates from the effects of GABAergic drugs in non-convulsive epilepsy. Even more striking is the role of the benzodiazepines, generally seen as GABA agonists; these drugs do not act as such in absence epilepsy since they reduce spike-wave discharges. Also good evidence for an involvement of other neurotransmitters such as noradrenaline, dopamine and opioid peptides exists in absence epilepsy. Genetic data obtained from the WAG/Rij model for absence epilepsy show a relatively simple pattern of inheritance with one gene determining whether an individual is epileptic or not, and with other genes regulating the number and duration of seizures. This is in good agreement with the more restricted human data. Cognitive studies have shown two important features of epilepsy in the WAG/Rij strain: modulation of the number of spike-wave discharges by mental or physical activity and on the other hand, the disruption of cognitive activity by spike-wave discharges.(ABSTRACT TRUNCATED AT 400 WORDS)     

Epileptiform EEG Activity of the Centromedian Thalamic Nuclei in Children with Intractable Generalized Seizures of the Lennox-Gastaut Syndrome

Centromedian thalamic nuclei (CM) epileptiform EEG activities were recorded in children with intractable generalized seizures of Lennox-Gastaut syndrome (LGS) through implanted recording-stimulating electrodes used for seizure control. Ictal CM epileptiform activities were consistently correlated to widespread surface cortical EEG activities and symptoms in all patients and all types of generalized seizures; i.e., fast spike discharges at CM correlated at onset of tonic and tonic-clonic generalized seizures; slow (1-2 Hz) spike-wave complex discharges at CM correlated for atypical absence seizures; slow polyspike-wave complex discharges correlated for myoclonic seizures; and spike bursts and suppression patterns correlated for combined tonic-atonic-myoclonic seizures. Ictal EEG activities occurred simultaneously at right and left CM and surface at onset of all seizure types, with the exception of myoclonic seizures where CM complete discharges and individual spike-wave complexes significantly lead those of the surface. Brief tonic-atonic spasms clinically undistinguishable from "real" epileptic seizures showed no EEG counterparts at CM and surface. Interictal CM spike-wave complete discharges and individual spike-wave complexes showed variable amplitude-temporal patterns. Amplitude emphasis on CM and frontopolar regions was observed in most of complete discharges, however, and phase shifts between CM and frontopolar regions were observed in individual spike-wave complexes.     

Olfactory stimulation induces delayed responses in epilepsy

Precipitation and inhibition of seizures and epileptic discharges by sensory stimuli are receiving increasing attention because they provide insight into natural seizure generation in human epilepsies and can identify potential nonpharmacological therapies. We aimed to investigate modulation (provocation or inhibition) of epileptiform discharges (EDs) in mesial temporal lobe epilepsy (MTLE) versus idiopathic generalized epilepsy (IGE) by olfactory stimulation (OS) compared with standard provocation methods. The underlying hypothesis was that any response would be more likely to occur in MTLE, considering the anatomical connections of the temporal lobe to the olfactory system. This multicenter, international study recruited patients with either MTLE or IGE who were systematically compared for responses to OS using an EEG/video-EEG protocol including a 30-min baseline, twice 3-min olfactory stimulation with ylang-ylang, hyperventilation, and intermittent photic stimulation. The 95% confidence interval (CI) for the baseline EDs in each patient was calculated, and modulation was assumed when the number of EDs during any 3-min test period was outside this CI. A total of 134 subjects (55 with MTLE, 53 with IGE, and 26 healthy controls) were included. Epileptiform discharges were inhibited during OS in about half the patients with both MTLE and IGE, whereas following OS, provocation was seen in 29.1% of patients with MTLE and inhibition in 28.3% of patients with IGE. Olfactory stimulation was less provocative than standard activation methods. The frequent subclinical modulation of epileptic activity in both MTLE and IGE is in striking contrast with the rarity of reports of olfactory seizure precipitation and arrest. Inhibition during OS can be explained by nonspecific arousal. The delayed responses seem to be related to processing of olfactory stimuli in the temporal lobe, thalamus, and frontal cortex.     

Role of the thalamus in the physiopathology of epilepsy

Early hypotheses on the origin of primary generalized epilepsy suggested a determinant role for the "centrencephalon" in the triggering of discharges of generalized spike-waves (GSW) and tonic-clonic crises (TCC). It was demonstrated in this respect that bilateral cortical spike-wave discharges at 3 c/sec were obtained by electrical stimulation of intralaminar nuclei in the rat. The role of the thalamus in the genesis of GSW and TCC was subsequently demonstrated in several experimental models. However, the thalamus is apparently not involved in the genesis of EEG manifestations of generalized epilepsy and most authors agree that the latter are of cortical origin since a) with or without cardiazol, generalized seizures may occur after ablation of cat thalamus; b) in the cat diffuse cortical application of dilute penicillin can reproduce signs of generalized epilepsy observed after systemic injection of penicillin to this animal; c) finally paroxysmal discharges which appear in subcortical structures in the photosensitive baboon are always preceded by frontal cortical spike-waves; similarly intermittent light stimulation-provoked TCC always arise from the frontal cortex and furthermore hemispheric synchronization of attacks disappears after callosotomy. These findings indicate that the origin of GSW and TCC, is not in the thalamus but that the latter nevertheless plays a role in their elaboration.     

Late-onset, "Gastaut type", childhood occipital epilepsy: an unusual evolution.

We report on two girls and one boy with clinical and electroencephalographic features of late-onset childhood epilepsy with occipital paroxysms of the "Gastaut type", showing an unusual evolution. Neurological examination and brain imaging were normal in all three. At the age of 7.5 years, eight years and ten years respectively, the three children presented with episodes of visual symptoms when awake, and in one of them, the seizures were occasionally followed by oculocephalic deviation. The interictal EEG showed bilateral occipital spike-wave activated by eye closing. In two patients, the occipital seizures had been immediately followed by typical absences, since onset; in the other patient, five months after onset. The ictal EEG showed irregular bilateral occipital spike-wave discharges during the visual symptoms, followed by generalized spike-wave activity during the typical absences. The typical absences were activated by hyperventilation; the EEG did not show continuous spikes and waves during slow sleep. These three patients, with typical electroclinical features of "Gastaut type", childhood occipital epilepsy, demonstrated an evolution which, to our knowledge, has not been previously described. We investigated whether this unusual, age-dependent evolution was due to secondary bilateral synchrony or if these electroclinical features represent two types of idiopathic epileptic syndromes in the same patients.     

Electrical status epilepticus lasting for 17 months without behavioural changes

In an 8-year-old girl a seizure occurred, lasting 45 min with loss of consciousness and deviation of the eyes, 2 days after the onset of mumps. Next day the EEG showed bilateral, synchronized, continuous 2.5-3.5 c/sec spike-wave discharges, more prominent over the posterior regions. The abnormality was suppressed on eye opening and replaced by delta activity and short duration spike-wave paroxysms. Mental activity, hyperventilation, and photic stimulation did not change the pattern. The same EEG pattern persisted during daytime sleep. This picture has lasted for 17 months without any associated epileptic manifestations or behavioural disturbances. Psychometric tests and CAT scan were normal.     

Electroencephalographic generalized features in idiopathic childhood focal epilepsies

PurposeIdiopathic focal epilepsies in childhood including benign childhood epilepsy with occipital paroxysms (BEOP) or benign childhood epilepsy with centro-temporal spikes (BCECTS) are characterized by specific focal electrographic patterns as the name indicates. Generalized spike-wave discharges in children with idiopathic focal epilepsy can suggest a neurobiological continuum with the idiopathic generalized epilepsies. We assessed the prevalence of generalized epileptiform discharges and generalized seizures in BEOP/BCECTS patients.MethodsBetween August 2005 and November 2008, we identified 220 cases with electroclinical features typical of idiopathic focal epilepsies, 172 patients with BCECTS and 48 patients with BEOP, excluding patients whose neurological examinations or brain MRI were abnormal. We analyzed gender, age at onset, manifestation of generalized seizures, and serial EEG records to detect generalized abnormalities.ResultsOf our population, 42 patients (19.1%, 22 boys), 30 (17.4%) of 172 BCECTS patients and 12 (25.0%) of 48 BEOP patients, showed generalized spike-wave discharges once or more during follow-up. The typical 3-Hz generalized spike wave discharge was noticed in 7 patients and concurrence with clinical generalized seizure was observed in 11.ConclusionA relatively high incidence of generalized spike-wave discharge and concurrence with generalized seizure were observed in patients with BEOP/BCECTS, with the incidence being higher in BEOP patients than in those with BCECTS. It may be inferred that idiopathic focal epilepsy is not a fixed syndrome but is a part of a broad, age-related, benign, seizure susceptibility syndrome.     

Neuropsychological correlates of subclinical paroxysmal EEG activity in children with epilepsy. 1: Qualitative features (generalized and focal abnormalities)

The cognitive deficit often associated with epilepsy is attributable to the presence and interaction of several factors but whether recurrent subclinical spike-wave discharges interfere with cognitive development is not yet clear. In the present study, the presence of subclinical discharges proved to be significantly associated with lower than average Full-Scale Intelligence Quotient (IQ), Verbal IQ and Performance IQ scores (Wechsler Intelligence Scale for Children) in comparison with patients not presenting EEG abnormalities during test. These findings confirm the adverse effect both of generalized and focal EEG epileptiform abnormalities, even if unaccompanied by overt seizures.     

Hypomotor seizures in infants and children

PURPOSE: Hypomotor seizures (characterized by diminished behavioral activity with indeterminate level of consciousness) have been identified as an important seizure type in infants. Our goal was to investigate further the clinical and EEG features of hypomotor seizures. METHODS: We retrospectively reviewed 110 hypomotor seizures from 34 patients recorded with video-EEG. RESULTS: Twenty-seven (79%) patients were younger than 48 months, and seven (21%) were aged 4 to 15 years. Seventy-one (64%) seizures had regional or lateralized EEG onset, arising predominantly from temporal or parietal lobe regions. The other 39 (35%) seizures had generalized onset, usually with abrupt onset of diffuse rhythmic high-amplitude theta activity or diffuse electrodecrement and only rarely (two patients) with slow spike-wave complexes or 3-Hz spike-wave complexes. Hypomotor seizures with generalized EEG onset were significantly shorter than those with regional or lateralized onset (p = 0.01, GEE model). Unsustained head or eye movements and subtle mouth automatisms were commonly seen in hypomotor seizures with either focal or generalized onset. Seventeen percent of hypomotor seizures with focal onset evolved to include version of head and eyes or jerking of one arm, whereas 2% of generalized hypomotor seizures evolved to a cluster of spasms. CONCLUSIONS: Hypomotor seizures may be either focal or generalized. Regional EEG onsets were most often temporal or parietal, suggesting that focal hypomotor seizures may be a bland form of "complex partial" seizures with no or minimal automatisms, seen predominantly in infants. Generalized hypomotor seizures were rarely associated with an ictal pattern of generalized spike-wave complexes, suggesting a different mechanism from absence seizures seen later in life.     

Epilepsy in offspring of whom both parents have idiopathic generalized epilepsy: biparental inheritance

BACKGROUND: Little is known about offspring of parents who both have idiopathic generalized epilepsy (IGE). This is of importance for understanding the complex genetic architecture of IGE.METHODS: Families in whom both parents had proven IGE were ascertained through a multiplex families database. Clinical information including EEG recordings and detailed pedigrees was obtained. RESULTS: In family I, the mother had juvenile myoclonic epilepsy (JME), and the father had IGE. One daughter had Lennox-Gastaut syndrome, and the other had unclassified epilepsy. In family II, the mother had JME, and the father had IGE. Two of three sons had an identical clinical picture of clinical picture of childhood absence epilepsy (CAE), but with fast polyspike-wave discharges on EEG. CONCLUSIONS: The clinical phenotype of affected offspring suggested that their epilepsy could be due to the combination of a putative "double dose" of genes from both sides of the family. In such families, as epilepsy genes could be inherited from both parents, a high risk of epilepsy in the offspring could be expected.