Are there generalised spike waves and typical absences in benign rolandic epilepsy?

Generalized Tonic-Clonic Seizures after Self-Limited Epilepsy with Centrotemporal Spikes: A Case Series

Purpose: Patients with self-limited epilepsy with centrotemporal spikes (SLECTS) rarely experience generalized tonic-clonic seizures (GTCS) after remission, and post-remission GTCS has not been thoroughly described in earlier studies. Herein, we describe the clinical and electrographic features of GTCS after a substantial period of seizure freedom in patients with SLECTS.Methods: This study included six patients (three boys and three girls) diagnosed with SLECTS who later developed GTCS after or near remission. Medical records, including clinical data and serial electroencephalography (EEG) recordings, were retrospectively reviewed for all patients.Results: Patients’ age at SLECTS onset ranged from 5.2 to 10.2 years (mean, 8.4 years), while seizure cessation was achieved between 8 and 12.2 years. During SLECTS, typical centrotemporal spikes were observed in all patients, and generalized spike-and-wave discharges were observed in three patients. The age at the first episode of subsequent GTCS ranged from 14.4 to 17.3 years (mean, 15.8 years), constituting an average interval of 5.6 years after the last episode of seizures (range, 4.1 to 8.1 years). EEG at subsequent episodes of GTCS revealed generalized discharges in two patients, focal discharges in two other patients, and normal discharges in the remaining two patients. Two patients had multiple episodes of GTCS.Conclusion: Although rare, GTCS may occur near or after remission in patients with SLECTS, and clinicians should be aware of this. Subsequent GTCS may be a manifestation of idiopathic generalized epilepsy. However, large-scale studies are needed to determine the nature of such episodes of GTCS and their associated risk factors.

Change of centrotemporal spikes from onset to remission in self-limited epilepsy with centrotemporal spikes (SLECTS)

OBJECTIVE

To reveal the changes of centrotemporal spikes that occur during the disease course of self-limited epilepsy with centrotemporal spikes (SLECTS).

METHOD

We retrospectively reviewed the serial EEGs of 63 patients with SLECTS from initial diagnosis to remission. There were 32 patients who did not undergo treatment and 31 patients who underwent treatment with oxcarbazepine (OXC). The change of occurrence or abundance, voltage, and location of centrotemporal spikes of serial EEGs were analyzed and compared between the two groups. Clinical seizure evidenced and reported was counted. The time gap between seizure remission and EEG remission was measured in the two groups.

RESULT

Changes of occurrence or abundance of the centrotemporal spikes were either abrupt (sudden disappearance of the frequent spikes on following EEG) or gradual (decline in number over 2 or more serial EEGs). Pattern of spike disappearance was not significantly different between the medication naïve group and OXC treated group. The spike voltage or the location of centrotemporal spikes did not change during the disease course in most cases. Delay between seizure remission and EEG normalization was 3.34 ± 1.75 (mean ± standard deviation, range: 0.77-7.97) years in untreated patients and 3.03 ± 1.41 (0.95-6.61) years in OXC-treated group.

CONCLUSION

Pattern of spike disappearance in SLECTS was either abrupt or gradual. Treatment with OXC had no effect in the disappearance pattern. Precise data regarding the pattern of disappearance and delay between seizure remission and EEG normalization can help to understand the evolution of spike in SLECTS and to predict the timing of normalization of EEG after seizure remission.

Co-existence of Rolandic and 3 Hz Spike-Wave Discharges on EEG in Children with Epilepsy

OBJECTIVE

Benign epilepsy of childhood with central temporal spikes (BECTS) and absence epilepsy are common epilepsy syndromes in children with similar age of onset and favorable prognosis. However, the co-existence of the electrocardiogram (EEG) findings of rolandic spike and 3 Hz generalized spike-wave (GSW) discharges is extremely rare, with few cases reported in the literature. Our objective was to characterize the EEG findings of these syndromes in children in our center and review the electro-clinical features.

METHODS

All EEGs at BC Children's Hospital are entered in a database, which include EEG findings and clinical data. Patients with both centro-temporal spikes and 3 Hz GSW discharges were identified from the database and clinical data were reviewed.

RESULTS

Among the 43,061 patients in the database from 1992 to 2017, 1426 with isolated rolandic discharges and 528 patients with isolated 3 Hz GSW discharges were identified, and 20 (0.05%) patients had both findings: 3/20 had BECTS, and subsequently developed childhood absence epilepsy and 17/20 had no seizures characteristic for BECTS. At follow-up, 17 (85%) were seizure-free, 1 (5%) had rare, and 2 (10%) had frequent seizures.

CONCLUSIONS

This is the largest reported group of patients to our knowledge with the co-existence of rolandic and 3 Hz GSW discharges on EEGs in one institution, not drug-induced. As the presence of both findings is extremely rare, distinct pathophysiological mechanisms are likely. The majority had excellent seizure control at follow-up, similar to what would be expected for each type of epilepsy alone.

Coexistence of childhood absence epilepsy and benign epilepsy with centrotemporal spikes: A case series

AIM

Childhood absence epilepsy (CAE) and benign childhood epilepsy with centrotemporal spikes (BECTS) are the most common forms of childhood epilepsy. Recent studies in animal models suggest that the two phenotypes may represent a neurobiological continuum. Although the coexistence of CAE and BECTS has been reported, this issue remains controversial. The purpose of this study was to analyse the electro-clinical characteristics of a group of children with contemporary or subsequent features of absence seizures and focal seizures consistent with BECTS.

MATERIAL AND METHODS

A systematic record review from 8 epilepsy centres was used to identify 11 subjects, 5 females and 6 males, with electro-clinical documented consecutive or contemporary coexistence of CAE and BECTS.

RESULTS

Patient's age ranged between 7.8 and 17.3 years. Four out of 11 patients presented concomitant features of both syndromes, whereas the remaining 7 experienced the two syndromes at different times.

CONCLUSIONS

Although CAE and BECTS are clearly defined syndromes and considered very different in terms of their pathophysiology, they share some features (such as similar age of onset, overall good prognosis), and can occur in the same patient. The long term prognosis of these patients seems to be good with an excellent response to anticonvulsant therapy.

Ethosuximide-induced conversion of typical childhood absence to Rolandic spikes

Coexistence of 2 idiopathic epilepsy syndromes (ie, childhood absence and Rolandic epilepsy), as evidenced by electroencephalographic (EEG) findings with or without clinical features of the 2 conditions, is uncommon and remains controversial. Few case reports support this coexistence either as a continuum or drug-induced conversion, whereas a large sample case review did not find such co-occurrence. The authors report a case of conversion of typical absence to Rolandic spikes after treatment with ethosuximide. An 11-year-old girl was diagnosed with typical childhood absence epilepsy at the age of 6 years with classic clinical and EEG features. She became seizure-free on ethosuximide but her follow-up EEGs consistently recorded right centrotemporal and centroparietal spikes without associated clinical seizures. This case may suggest simultaneous presence of these 2 common childhood idiopathic epilepsies either as a continuum or a drug-induced conversion.

Two epileptic syndromes, one brain: childhood absence epilepsy and benign childhood epilepsy with centrotemporal spikes

Childhood absence epilepsy (CAE) and benign childhood epilepsy with centrotemporal spikes (BCECTS), or benign rolandic epilepsy (BRE), are the most common forms of childhood epilepsy. CAE and BCECTS are well-known and clearly defined syndromes; although they are strongly dissimilar in terms of their pathophysiology, these functional epileptic disturbances share many features such as similar age at onset, overall good prognosis, and inheritance factors. Few reports are available on the concomitance of CAE and BCECTS in the same patients or the later occurrence of generalized epilepsy in patients with a history of partial epilepsy. In most cases described in the literature, absence seizures always started after the onset of benign focal epilepsy but the contrary has never occurred yet. We describe two patients affected by idiopathic generalized epileptic syndrome with typical absences, who experienced BCECTS after remission of seizures and normalization of EEG recordings. While the coexistence of different seizure types within an epileptic syndrome is not uncommon, the occurrence of childhood absence and BCECTS in the same child appears to be extremely rare, and this extraordinary event supports the hypothesis that CAE and BCECTS are two distinct epileptic conditions. However, recent interesting observations in animal models suggest that BCECTS and CAE could be pathophysiologically related and that genetic links could play a large role.

Childhood absence epilepsy in patients with benign focal epileptiform discharges

Few reports are available of ictal recordings in patients with benign focal epileptiform discharges. The study objective was to estimate the frequency of such recordings and to describe their clinical and electrophysiologic presentation. We performed a retrospective chart review of all patients undergoing routine electroencephalography (EEG) with video during a 10-year period. Among 214 patients with benign focal epileptiform discharges, 5 patients were identified with recorded EEG seizures (2.3%). Epilepsy syndromes included one case of benign focal epilepsy of childhood, three cases of childhood absence epilepsy, and in one case the patient presented with both. Only 1 of the 214 patients (0.4%) had a seizure characteristic of benign focal epilepsy of childhood. A literature review revealed the coexistence of childhood absence and benign focal epilepsy of childhood or benign focal epileptiform discharges within the same patient. These findings suggest that benign focal epilepsy of childhood seizures are rarely recorded during routine EEG, probably because seizures occur during the early morning part of the sleep cycle, which may differ from the brief nap during routine EEG. There was concurrence of generalized spike and wave discharges in these patients. It is unclear whether this is related to a common pathophysiologic factor.

COMPARISON OF EPILEPTIC AND NONEPILEPTIC CASES WITH CENTROTEMPORAL SPIKES IN VIEW OF CLINICAL FINDINGS AND ELECTROENCEPHALOGRAPHIC CHARACTERISTICS

The morphological features of centrotemporal spike discharges (CTSD) and relationship of them with clinical diagnosis in cases with benign epilepsy of childhood with centrotemporal spikes (BECTS) and the other epileptic syndromes of childhood as well as some nonconvulsive neurological disorders were detected in the routine patient population who referred to the authors' EEG laboratory. Thirty-six cases (21 males, 15 females; 8 months-14 years old), in which awake and/or sleep EEGs revealed CTSD were included in this study. The cases were divided into two groups as epileptic and nonepileptic. The cases with seizure were divided into BECTS and the other epilepsies. Of the epileptic cases, 14 (38.8%) patients had typical rolandic seizures. In five cases, there were partial or secondary generalized seizures. Two cases had myoclonic seizures. In the nonepileptic group, there was mental retardation/behavioral disturbances in five cases; there were periodic syndromes of childhood such as migraine and equivalents of migraine in three cases; febrile convulsion in three cases, breath-holding spells in two cases, and primary enuresis nocturna in two cases. In the nonepileptic group, the discharges were significantly fewer than the other groups (p = .014). More frequent discharges occuring for shorter periods were more significantly observed in BECTS group (64%). Typically isolated spike and slow-waves in T3/T4 and C3/C4 location were significantly more common (86%) in rolandic epilepsy group (p = .01). The EEGs of cases with BECTS had more frequency in the cluster of discharges than the other groups (p = .018). Multifocal discharges were observed in 28.5% of cases with BECTS, in 20% of nonepileptic group, and in 71.4% of other epileptics in the trial. Although these epileptic and nonepileptic conditions have some differences in view of frequency and morphology and location, CTSDs could be manifested in the group without seizure. It was concluded that the similar focal abnormalities which could be seen in rolandic epilepsy may be observed in the other epileptic or nonepileptic disorders of childhood and this condition may be originated from the involvement of similar central structures.

EEG Characteristics Related to Educational Impairments in Children with Benign Childhood Epilepsy with Centrotemporal Spikes

PURPOSE

Learning and behavioral difficulties often occur in benign childhood epilepsy with centrotemporal spikes (BCECTS). In recent years, several electroencephalogram (EEG) characteristics have been related to the occurrence of learning and behavioral problems.

METHODS

From 28 children medical, school and psychological reports were present and children were rated according to a 4-point scale for educational and behavioral impairment (Part 1). Thirty 24-h EEG recordings were reanalyzed for spike frequency, the presence of atypical EEG criteria, and the presence of a nondipole spike. EEGs were scored during wakefulness, first hour of sleep and whole night sleep (minus the first hour of sleep) separately (Part 2).

RESULTS

The presence of I: an intermittent slow-wave focus during wakefulness, II: a high number of spikes in the first hour of sleep (and during whole night sleep), and III: multiple asynchronous bilateral spike-wave foci in the first hour of sleep correlates significantly with a sum score > or = 3 which indicates a complicated course with educational or behavioral impairment. It is sufficient to analyze an EEG during wakefulness and a sleep EEG for only the first hour of sleep instead of a whole night recording to demonstrate those EEG criteria.

CONCLUSIONS

On basis of our reanalysis we can possibly conclude that the aforementioned EEG characteristics correlate with educational impairments, and that analysing an EEG recording during wake and the first hour of sleep is sufficient to look adequately for those EEG criteria in children with BCECTS.

Coexistence of childhood absence and rolandic epilepsy

The coexistence of absence and rolandic epilepsy is extremely rare. This coexistence has been attributed to either the treatment or an atypical course of the disease. However, for some authors, this issue remains controversial. We report the case of a 9-year-old girl presenting with both absence seizures and focal seizures consistent with rolandic epilepsy.

Typical absence seizures associated with localization-related epilepsy: A clinical and electroencephalographic characterization

INTRODUCTION

This paper describes the characteristics of patients with typical absence seizures associated with localization related epilepsy (LRE) and compares electroclinical features of absences occurring in these patients with those having childhood absence epilepsy (CAE).

METHODS

Consecutive patients presenting with both LRE and typical absences in their epilepsy history were included in the study (Group 1). Clinical assessments and EEG investigations were conducted during the follow-up. Patients observed during the same period, but with typical absences fulfilling the CAE diagnostic criteria, were assigned to a second group (Group 2).

RESULTS

Fourteen patients were included in Group 1. These patients had a mean age at their last visit of 11.3 years (range 7.2-16.8), with a mean follow-up period of 6.8 years. In all patients LRE was the first type of seizure to occur at median age of 4.95+/-2.1 years (range 1.9-8.8). Typical absences appeared at median age of 7.5+/-2.5 years (range 4.5-12.5), and were well controlled by therapy. Ictal EEG and semiology features of typical absences did not show any distinctive features when compared to those of Group 2 represented by 53 patients affected by CAE. However, age at onset was significantly higher in Group 1, as was the number of patients who underwent polytherapy, and the number with relapses after drug discontinuation. None of patients in Group 1 showed terminal remission.

CONCLUSION

Although clinically heterogeneous and rare, the association of LRE with typical absences may be more than coincidental. In these patients, typical absences responded well to therapy, but terminal remission rates were lower than for CAE patients.

Spike morphology, location, and frequency in benign epilepsy with centrotemporal spikes

The literature on benign epilepsy with centrotemporal spikes reports a constellation of neurophysiologic features in selected populations with heterogeneous methodologies. The aim of this study was to determine the specific electroencephalographic (EEG) features (spike morphology, location, and frequency and associated background slowing) in a broad population-based cohort identified through EEG laboratories. The mean spike frequency in the awake state was 9.3 per minute (95% confidence interval 6.5-12.0), in drowsiness, 21.2 per minute (16.7-25.6); and in sleep, 45.6 per minute (38.3-52.8), where 60% of patients had > 40 discharges per minute. In five patients, spike train rates occupied > 80% of the sleep record, and in nine patients, they occupied 61% to 80%. An ambulatory overnight record did not add new information comparing early-onset sleep with a mean spike frequency of 37.1 per minute (27.3-46.9) with slow-wave sleep, 36.0 per minute (27.3-44.7). Patients with benign epilepsy with centrotemporal spikes have a high spike burden, which can impact on cognitive function.

Idiopathic occipital and absence epilepsies appearing in the same children

Our aim is to report the association between idiopathic occipital epilepsy and childhood absence epilepsy in the same children. Six children met the diagnostic criteria for both idiopathic occipital epilepsy and childhood absence epilepsy, five patients with idiopathic occipital epilepsy Gastaut type and another with Panayiotopoulos type. All patients were monitored for 2 to 10 years with repeated electroencephalograms when awake and during sleep. Age at onset of seizures ranged from 4.6 to 8 years. Five patients had focal sensory visual seizures, all with migraine-like episodes. One patient presented ictal vomiting followed by oculocephalic deviation. All patients presented typical absences, with onset at least 1 year after having had idiopathic occipital epilepsy Gastaut type in three patients. In the other two patients with idiopathic occipital epilepsy Gastaut type and the patient with idiopathic occipital epilepsy Panayiotopoulos type, both types of epilepsy appeared at the same time. The electroencephalograms documented occipital paroxysms in all cases, with positive reactivity to the eye closure in five patients. All children presented spike-wave discharges at 3 cycles per second activated by hyperventilation. More genetic information would be necessary to demonstrate either a close genetic relationship between these syndromes or common markers with variable phenotypes.

Abnormal neuroimaging in patients with benign epilepsy with centrotemporal spikes

PURPOSE

Neuroimaging procedures are usually unnecessary in benign epilepsy of childhood with centrotemporal spikes (BECTS) but are often performed before a specific diagnosis has been reached. By definition, BECTS occurs in normal children; however, recent reports have shown that it also can affect children with static brain lesions. We evaluated the prevalence of abnormal neuroimaging in BECTS and assessed whether the lesions had influenced the clinical and EEG expression of this epilepsy.

RESULTS

Among 98 consecutive cases first referred between 1984 and 1999, neuroimaging had been performed in 71 (72%) [magnetic resonance imaging (MRI), 20; computed tomography (CT), 59; MRI+CT, eight]. In ten (14.8%), neuroradiologic procedures were abnormal: enlargement of lateral venticles in five cases including a shunted hydrocephalus in two (no etiology in one, neonatal intraventricular hemorrhage in one), a moderate ventricular dilation in one (neonatal distress), a slight ventricular dilation and hypersignal intensities in the white matter in one (premature birth at 27 weeks), and a moderate enlargement of the right temporal horn in one. A right hippocampal atrophy, a biopercular polymicrogyria, a cavum septum pellucidum, a small cystic lesion located in the epiphysis, and an agenesis of the corpus callosum with macrocrania also were observed once each. The outcome was benign in all, in accordance with the overall prognosis of BECTS.

CONCLUSIONS

This study confirms that neuroimaging may be abnormal in patients with BECTS and shows that the presence of brain lesions has no influence on the prognosis. Conversely, BECTS can be diagnosed in patients with brain lesions with or without significant neurologic history or abnormalities.

Coincidence of rolandic and absence features: rare, but not impossible

The purpose of the study was to evaluate the incidence of a possible combination of rolandic and absence signs in epileptic children, which remains a subject of controversy. The medical files and electroencephalographic (EEG) records of children with rolandic, childhood absence, and juvenile absence epilepsy were retrospectively analyzed. During the antiepilepsy treatment, 6 of 66 patients with rolandic epilepsy, most of them with initial carbamazepine therapy, had absences and generalized spike-wave discharges of a secondarily generalized type. Five cases of 34 children with childhood absence epilepsy and 3 of 11 patients with juvenile absence epilepsy were identified with an EEG focus of the rolandic type. We considered the likely relation of absence features in rolandic epilepsy to the treatment or to an atypical course. The presence of a rolandic focus in absence epilepsies, however, makes the coincidence of these entirely distinct phenomena, even if very rare, not excluded. Further studies are required to elucidate a probable genetic or functional link between partial and primarily generalized EEG discharges in the idiopathic childhood epilepsies.

Ictal single photon emission computed tomography in absence seizures: apparent implication of different neuronal mechanisms

Absence seizures represent a complex group of epilepsy, characterized by lapse of consciousness with staring. Bilateral, synchronous, and symmetric bursts of 3-Hz spike-and-wave discharges are observed on the electroencephalogram, whereas interictal background activity is normal. This kind of epilepsy has to be differentiated from other generalized epilepsies such as juvenile absence epilepsy and juvenile myoclonic epilepsy. Moreover, absence seizures, together with generalized spike-and-wave discharges, may coexist with other types of epilepsy such as frontal lobe epilepsy, temporal lobe epilepsy, benign epilepsy with centrotemporal spikes, and childhood epilepsy with occipital paroxysms. We have carried out ictal single photon emission computed tomography (SPECT) in 10 patients with clinical evidence of absence seizures with the aim to better understand and to distinguish this kind of seizure as primarily or secondarily generalized to a specific area and to obtain more information on the neuronal mechanisms involved in the different types of seizures, usually not identifiable at the first appearance. During the long follow-up period (9 months to 14 years), 7 of the 10 examined patients underwent interictal SPECT when they became seizure free. Our data permitted, in two patients, the diagnosis of childhood absence seizures; in three patients, they suggested the possibility of later appearance of other seizure types, on the basis of focal hyperperfusion indicating a possible focal firing. In three of the examined patients, the diagnosis of idiopathic localization-related epilepsies mimicking childhood absence seizures could be performed. In the last two patients, the hypothesis of a coexistence of absences with partial and generalized seizures was considered. From our results, it can be presumed that ictal SPECT findings may contribute to the physiopathologic classification of the different types of epilepsies. Moreover, anticonvulsant treatment more appropriate to the different forms of seizures can be used.