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.

OBJECTIF: L'épilepsie bénigne de l'enfance à pointes centro-temporales (ou épilepsie rolandique bénigne [ERB]) et l'absence épileptique sont des syndromes épileptiques communs chez des enfants dont le pronostic est favorable et dont l'apparition des premiers symptômes s'est produite à un âge similaire. Cependant, la coexistence, lors d'EEG, de résultats montrant des décharges rolandiques et des décharges à pointes-ondes continues de 3 Hz demeure extrêmement rare, peu de cas ayant été signalés dans la littérature scientifique. Notre objectif a donc consisté à décrire les résultats d'EEG liés à ces syndromes dans le cas d'enfants fréquentant notre établissement et à examiner leurs caractéristiques électro-cliniques. MÉTHODES: En plus de certaines données cliniques, tous les résultats d'EEG réalisés au BC Children's Hospital sont saisis dans une base de données. Tant les jeunes patients donnant à voir des décharges à pointes centro-temporales que ceux atteints de décharges à pointes-ondes continues de 3 Hz ont été identifiés à partir de cette base de données. Leurs données cliniques ont été ensuite passées en revue. RÉSULTATS: Sur un total de 43 061 jeunes patients présents dans la base de données de 1992 à 2017, nous en avons identifié 1426 avec des décharges rolandiques isolées et 528 avec des décharges isolées à pointes-ondes de 3 Hz. À noter que seulement vingt d'entre eux, soit 0,05 %, étaient concernés par ces deux types de décharge. À cet égard, 3 sur 20 étaient atteints d'ERB et ont développé ultérieurement un syndrome d'absence épileptique; chez les 17 autres, aucune convulsion caractéristique de l'ERB n'a été observée. Lors d'un suivi, 17 (85 %) d'entre eux n'avaient plus de crises convulsives tandis que 1 (5 %) avait exceptionnellement des crises et 2 (10 %), des crises fréquentes. CONCLUSIONS: À notre connaissance, il s'agit là du plus vaste groupe déclaré de patients donnant à voir, lors d'EGG menés au sein d'un seul établissement, une coexistence entre des décharges rolandiques et des décharges à pointes-ondes de 3 Hz, et ce, sans qu'elles n'aient été causées par des médicaments. Considérant que la présence de ces deux phénomènes est particulièrement inhabituelle, le rôle de divers mécanismes pathophysiologiques est fort probable. Fait à souligner, la majorité de ces patients ont pu montrer, au moment de leur suivi, une excellente maîtrise de leurs crises convulsives, maîtrise semblable à celle à laquelle on pourrait s'attendre pour chaque type d'épilepsie pris individuellement.

Outcome of Absence Epilepsy With Onset at 8-11 Years of Age: Watershed Ages When Syndromes Overlap.

Introduction: Absence seizures occur in various epilepsy syndromes, including childhood and juvenile absence epilepsy and juvenile myoclonic epilepsy. When children present with absence seizures at ages when syndromes overlap, initial syndrome designation is not always possible, making early prognostication challenging. For these children, the study objective is to determine clinical and initial electroencephalograph (EEG) findings to predict the development of generalized tonic-clonic seizures, which is a factor that affects outcome. Methods: Children with new-onset absence seizures between 8 and 11 years of age with at least 5 years of follow-up data were studied through the review of medical records and initial EEG tracings. Results: Ninety-eight patients were included in the study. The median age of absence seizure onset was 9 years (interquartile range [IQR] = 8.00, 10.00) and follow-up was 15 years (IQR = 13.00, 18.00). Forty-six percent developed generalized tonic-clonic seizures and 20% developed myoclonic seizures. On multiple regression analysis, a history of myoclonic seizures, anxiety, as well as bifrontal slowing and mild background slowing on initial EEG (P < .05) were associated with generalized tonic-clonic seizures. Although not statistically significant, a shorter duration of shortest EEG burst on baseline EEG was also associated with generalized tonic-clonic seizures. Conclusion: On initial EEG, bifrontal and background slowing and myoclonic seizures and anxiety are associated with developing generalized tonic-clonic seizures, which is of prognostic significance when early syndrome designation is difficult.

Pediatric Occipital Spikes at a Single Center Over 26 Years and the Significance of Tangential Dipole.

BACKGROUND: Pediatric occipital epileptiform discharges occur in various clinical settings, including self-limited and treatment-resistant epilepsies. The study objective is to determine electro-clinical predictors for prognosis in children with occipital epileptiform discharges. METHODS: 205 patients with occipital epileptiform discharges were classified into seizure groups: self-limited occipital (SLO) (n = 57), including Panayiotopoulos and Gastaut syndrome; non-self-limited occipital (non-SLO) (n = 98), including various seizure etiologies; genetic-generalized (n = 18); febrile (n = 5); and no-seizure (n = 27) groups. Electro-clinical features of the SLO and non-SLO were compared, as this is of most clinical relevance. RESULTS: The median age of seizure onset was 3 years (range: 0-19). Occipital epileptiform discharges with frontal/central positivity were present in both groups, but more common in the SLO than non-SLO groups; 21/57 (36.8%) and 19/98 (19.4%), respectively (P < .022). However, when occipital epileptiform discharges with tangential dipoles (P < .048) were accompanied by abnormal ictal eye movements (P < .037), they were predictive of SLO epilepsy. CONCLUSIONS: In our cohort, occipital epileptiform discharges with tangential dipole detected by visual analysis and abnormal ictal eye movements were predictive of SLO epilepsy.

Clinical Significance of Incidental Rolandic Spikes in Children With Absence Epilepsy.

PURPOSE: Absence epilepsy and benign epilepsy of childhood with central temporal spikes are common childhood epilepsy syndromes. Although 3-Hz generalized spike-wave discharges are almost always associated with absence seizures, rolandic spikes can be present in individuals without rolandic seizures. The co-occurrence of 3-Hz generalized spike-wave and rolandic spikes is very rare. Our objective was to compare clinical features of patients with absence epilepsy with and without rolandic spikes, to determine if the additional feature of rolandic spikes has any clinical significance. METHODS: Clinical information of 17 children with absence epilepsy and rolandic spikes was compared to an age-matched control group of 90 children with absence epilepsy. RESULTS: Although most patients had excellent seizure control at follow-up, epilepsy comorbidities (cognitive and emotional problems) were observed. Comparing study vs control groups, there was no difference with anxiety (2 [11.8%] vs 8 [9%]), behavioral issues (4 [23.5%] vs 10 [11%]), mood disorders (0 vs 2 [2%]), and attention-deficit hyperactivity disorder (4 [24%] vs 10 [11%]). Significant differences were also observed: more global-developmental (5 [29%] vs 5 [6%], P < .009) and expressive-language (4 [24%] vs 5 [6%], P < .034) delay and more difficulties with school performance (11 [65%] vs 32 [36%], P < .025), especially with language-related tasks (6 [35%] vs 5 [6%], P < .001). CONCLUSION: Our results confirm the presence of additional epilepsy comorbidities in patients with absence epilepsy when rolandic spikes are present. Rolandic spikes in patients with absence epilepsy may be a marker of additional cognitive challenges that physicians should be aware of.

Predictive Value of Midline Spikes on Pediatric EEG for Seizure and Developmental Outcome.

PURPOSE: Midline spikes are epileptiform discharges localized to the midsagittal regions of the brain. Isolated midline spikes are rare, but more common in children. Our objective was to determine whether midline spikes are predictive of seizure characteristics and neurodevelopment. METHODS: EEGs and clinical information of 123 children with isolated midline spikes, and EEG follow-up within 12 to 24 months, were reviewed and compared with controls. RESULTS: Most children with midline spikes had seizures (91%), with an equal predisposition to focal or generalized seizure semiology. There was no difference between the midline spike and control groups in terms of neonatal complications, seizure characteristics (type, frequency, and etiology), and neurologic examination findings. In patients with abnormal neuro-maging, deep gray or white matter abnormalities were more frequent in the midline group (41% vs. 13%, P = 0.02). The midline group had a higher risk of development delay (DD) than controls (43% vs. 29%, odds ratio: 1.8, 95% CI [1.1-3.2], P = 0.03). A higher risk of DD was also noted in the midline group in those aged less than 4 years (52% vs. 26%, odds ratio: 3.1, 95% CI [1.0-9.2], P = 0.04) and in those without seizures (40% vs. 17%, odds ratio: 3.16, 95% CI [1.1-8.8], P = 0.03). CONCLUSIONS: This is the largest reported group of patients with midline spikes. Midline spikes have a strong association with seizures and DD. Our data suggest that midline spikes result from heterogeneous etiologies, are more common in young children, and are not benign.