Seizures in Series: Similarities Between Seizures of the West and Lennox-Gastaut Syndromes

We observed seizures resembling infantile spasms in patients with Lennox-Gastaut syndrome (LGS). Infantile spasms, the type of seizures that occurs in patients who have West syndrome, have been well characterized by video-EEG studies and typically occur as a series of sudden generalized flexor or extensor jerks. The seizure types that occur in LGS have not been as clearly delineated. Some patients with West syndrome (WS) in early infancy later develop LGS. Using intensive video-EEG monitoring, we evaluated 14 LGS patients who had seizures that occurred in series. Clinically, the seizures greatly resembled infantile spasms, and the ictal EEG changes were identical to those that occur with infantile spasms. These findings expand the number of features known to be shared by these two syndromes and strengthen the hypothesis that the two syndromes represent age-related manifestations of similar epileptogenic processes.     

Asymmetric and Asynchronous Infantile Spasms

Summary: Infantile spasms most commonly show symmetric behavioral and electroencephalogram (EEG) manifestations. Asymmetric and asynchronous behavioral spasms occur occasionally, but their relationship to ictal EEG and to other localizing studies has not received much attention. We reviewed 75 consecutive video-EEG recordings, done at UCLA from 1982 to 1992, that contained infantile spasms; 8,680 spasms were scored for behavioral and EEG asymmetry and asynchrony. Of the recorded spasms, 25% were asymmetric and 7% were asynchronous. Most asymmetric or asynchronous spasms were associated with an ictal EEG discharge that was contralateral to the behaviorally more involved side. In 12 of the 60 patients (20%), more than half of the recorded spasms were asymmetric or asynchronous,. Baseline EEG, magnetic resonance imaging, positron emission tomography, and neurological examination revealed structural and functional brain abnormalities that involved the contralateral central region significantly more often in the children with >50% spasm asymmetry or asynchrony than in the other children. Partial seizures with lateralized motor behavior also occurred frequently in these children. The findings suggest that asymmetric and asynchronous spasms are generated by a cortical epileptogenic region that involves the primary sensorimotor area. The combination of asymmetric and asynchronous infantile spasms, partial motor seizures involving the same side of the body, and pathology in the contralateral central region may represent a unique subset of symptomatic localization-related infantile epilepsy.     

Infantile spasms and Lennox-Gastaut syndrome

Infantile spasms and Lennox-Gastaut syndrome are rare but are important to child neurologists because of the intractable nature of the seizures and the serious neurologic comorbidities. New antiepileptic drugs offer more alternatives for treating both infantile spasms and Lennox-Gastaut syndrome. Selected children with infantile spasms are candidates for epilepsy surgery. Vagus nerve stimulation, corpus callosotomy, and the ketogenic diet are all options for selected children with Lennox-Gastaut syndrome. The epidemiology, clinical manifestations of the seizures, electroencephalographic characteristics, prognosis, and treatment options are reviewed for infantile spasms and Lennox-Gastaut syndrome. Additional therapies are needed for both infantile spasms and Lennox-Gastaut syndrome as many children fail to achieve adequate seizure control in spite of newer treatments.     

Long-term prognosis of tuberous sclerosis with epilepsy in children

A follow-up study was performed on 40 children with tuberous sclerosis and epilepsy. In 68% of the patients with infantile spasms and 73% of those without them, complex partial seizures were observed. Thus, patients with tuberous sclerosis are subject to not only infantile spasms but also complex partial seizures. Patients with infantile spasms showed mental retardation more often than those without. Seizures which had evolved from infantile spasms were more difficult to control than those which had not. The prognosis of infantile spasms associated with tuberous sclerosis was better than that of prenatal group other than tuberous sclerosis. Forty percent of the 40 cases showed asymmetry on EEG, and the asymmetry tended to disappear as the patients grew up.     

Facilitation of Infantile Spasms by Partial Seizures

Summary: We report 16 patients with infantile spasms in whom onset of the clusters of spasms appeared to be triggered by close temporal association with partial seizures. Common features included the presence of focal cerebral lesions in 12 infants (3 were classifiable as cryptogenic); all had partial seizures with EEG localization, clusters of bilateral spasms always preceded by partial seizures, and response to adrenocorticotropic hormone (ACTH) and traditional antiepileptic drugs (AEDs) generally was poor. Three had complete agenesis of the corpus callosum, which argues against interhemispheric callosal spread of focal discharges resulting in the generalized spasms. Surgical cortical resections were performed in 6 of the infants, with good outcomes. This group of patients supports a model in which the spasms, although probably generated at a subcortical level, are facilitated or possibly induced by focal discharges from cortical pathology.     

Partial seizures triggering infantile spasms in the presence of a basal ganglia glioma.

Infantile spasms associated with brain tumors have been reported. A focal cortical lesion can induce infantile spasms by triggering the brainstem and basal ganglia in this vulnerable age group. We report the case of a female infant with a low-grade glioma in the right basal ganglia, spreading to the cortical area. She presented at the age of five months with left hemiparesis and partial seizures. She developed infantile spasms at the age of 12 months. This is the first video clip report of partial seizures triggering symmetrical spasms in series, secondary to a basal ganglia glioma extending to the cortex. [Published with video sequences].     

Mental and behavioural outcome of infantile epilepsy treated by vigabatrin in tuberous sclerosis patients

Vigabatrin (VGB) has demonstrated high efficacy in infantile spasms (IS) due to tuberous sclerosis. Our first objective was to evaluate the cognitive long term effect outcome of children whose refractory spasms definitely disappeared when VGB was given as an add on drug. Our second objective was to determine the response of generalized epilepsy (infantile spasms) compared to partial epilepsy on cognitive impairment. A non selected series of 13 children underwent psychometric and behavioural evaluation before VGB initiation at a mean of 3 years on VGB treatment. Eight of them could perform detailed neuropsychological tests at follow-up. Seven had infantile spasms (Group I), they all were spasm free before 2 years of age and five remained with rare partial seizures (mean age, 5.5 years). Six others had partial epilepsy without spasms (Group II) and five remained with rare seizures (mean age, 7.5 years). Patients of Group I experienced dramatic changes. Developmental quotient (DQ) significantly rose in six out of seven by ten to more than 45 points (P = 0.03) and autistic behaviour disappeared in five out of the six who presented with. The four tested children had normal verbal level after 5 years and could integrate at school but they remained with marked visuospatial disabilities. By contrast, patients of Group II remained with an unchanged DQ of about 60 so that both groups had similar DQ levels on follow-up. The cessation of spasms with VGB is therefore associated with significant improvement of cognition and behaviour in children with tuberous sclerosis. Controlling secondary generalization induced by infantile spasms seems to be a key factor for mental development.     

Possible induction of West syndrome by oxcarbazepine therapy in a patient with complex partial seizures

Oxcarbazepine has been reported to precipitate myoclonic, generalised tonic-clonic, absence, and complex partial seizures, and carbamazepine to precipitate absences, myoclonic seizures and spasms. Here, we report a one-year, six-month-old girl with complex partial seizures who developed infantile spasms, developmental regression, and hypsarrhythmia during the two weeks directly following initiation of oxcarbazepine (14?mg/kg/day). All of these resolved within a few days after discontinuation of this medication. Although we cannot rule out that the above association may have been coincidental, or that the improvement may have been due to concurrent therapy, this case raises the possibility that oxcarbazepine, like carbamazepine, may precipitate infantile spasms and West syndrome.     

Effect of multiple subpial transection on patients with uncontrolled atypical infantile spasms

We report a favorable outcome of multiple sub-pial transaction (MST) in two patients who had intractable atypical infantile spasms preceded by partial seizures, without any lateralized magnetic resonance imaging (MRI) abnormalities.