Rolandic Spikes Research Articles

Resting-State EEG Functional Connectivity in Children with Rolandic Spikes with or without Clinical Seizures.

Alterations in dynamic brain network function are increasingly recognized in epilepsy. Benign childhood epilepsy with centrotemporal spikes (BECTS), or benign rolandic seizures, is the most common idiopathic focal epilepsy in children. In this study, we analyzed EEG functional connectivity (FC) among children with rolandic spikes with or without clinical seizures as compared to controls, to investigate the relationship between FC and clinical parameters in children with rolandic spikes. The FC analysis based on graph theory and network-based statistics in different frequency bands evaluated global efficiency, clustering coefficient, betweenness centrality, and nodal strength in four frequency bands. Similar to BECTS patients with seizures, children with rolandic spikes without seizures had significantly increased global efficiency, mean clustering coefficient, mean nodal strength, and connectivity strength, specifically in the theta frequency band at almost all proportional thresholds, compared with age-matched controls. Decreased mean betweenness centrality was only present in BECTS patients with seizures. Age at seizure onset was significantly positively associated with the strength of EEG-FC. The decreased function of betweenness centrality was only presented in BECTS patients with clinical seizures, suggesting weaker local connectivity may lower the seizure threshold. These findings may affect treatment policy in children with rolandic spikes.

Source EEG reveals that Rolandic epilepsy is a regional epileptic encephalopathy

Rolandic epilepsy is the most common form of epileptic encephalopathy, characterized by sleep-potentiated inferior Rolandic epileptiform spikes, seizures, and cognitive deficits in school-age children that spontaneously resolve by adolescence. We recently identified a paucity of sleep spindles, physiological thalamocortical rhythms associated with sleep-dependent learning, in the Rolandic cortex during the active phase of this disease. Because spindles are generated in the thalamus and amplified through regional thalamocortical circuits, we hypothesized that: 1) deficits in spindle rate would involve but extend beyond the inferior Rolandic cortex in active epilepsy and 2) regional spindle deficits would better predict cognitive function than inferior Rolandic spindle deficits alone. To test these hypotheses, we obtained high-resolution MRI, high-density EEG recordings, and focused neuropsychological assessments in children with Rolandic epilepsy during active (n = 8, age 9–14.7 years, 3F) and resolved (seizure free for > 1 year, n = 10, age 10.3–16.7 years, 1F) stages of disease and age-matched controls (n = 8, age 8.9–14.5 years, 5F). Using a validated spindle detector applied to estimates of electrical source activity in 31 cortical regions, including the inferior Rolandic cortex, during stages 2 and 3 of non-rapid eye movement sleep, we compared spindle rates in each cortical region across groups. Among detected spindles, we compared spindle features (power, duration, coherence, bilateral synchrony) between groups. We then used regression models to examine the relationship between spindle rate and cognitive function (fine motor dexterity, phonological processing, attention, and intelligence, and a global measure of all functions). We found that spindle rate was reduced in the inferior Rolandic cortices in active but not resolved disease (active P = 0.007; resolved P = 0.2) compared to controls. Spindles in this region were less synchronous between hemispheres in the active group (P = 0.005; resolved P = 0.1) compared to controls; but there were no differences in spindle power, duration, or coherence between groups. Compared to controls, spindle rate in the active group was also reduced in the prefrontal, insular, superior temporal, and posterior parietal regions (i.e., “regional spindle rate”, P < 0.039 for all). Independent of group, regional spindle rate positively correlated with fine motor dexterity (P < 1e-3), attention (P = 0.02), intelligence (P = 0.04), and global cognitive performance (P < 1e-4). Compared to the inferior Rolandic spindle rate alone, models including regional spindle rate trended to improve prediction of global cognitive performance (P = 0.052), and markedly improved prediction of fine motor dexterity (P = 0.006). These results identify a spindle disruption in Rolandic epilepsy that extends beyond the epileptic cortex and a potential mechanistic explanation for the broad cognitive deficits that can be observed in this epileptic encephalopathy.

The Correlation of ELP4-PAX6 With Rolandic Spike Sources in Idiopathic Rolandic Epilepsy Syndromes.

Objective: To study the single nucleotide polymorphism rs662702 of ELP4-PAX6 in patients with idiopathic rolandic epilepsy syndromes (IRES) in China and explore the relationship between the distribution of rolandic spike sources and the single nucleotide polymorphism rs662702 in ELP4-PAX6.Methods: First, clinical information was obtained from patients diagnosed with IRES. Next, the single nucleotide polymorphism rs662702 of ELP4 was analyzed by using the Sanger method. Resting-state magnetoencephalography data were collected from 17 patients. We analyzed the epileptic spike sources using the single equivalent current dipole (SECD) model and determined the spike distributions across the whole brain. Finally, Fisher's test was performed to assess the correlation between the single nucleotide polymorphism rs662702 of ELP4-PAX6 and rolandic spike sources.Results: ELP4 rs662702 T alleles were found in 10.7% of IRES patients and occurred four times more frequently in these patients than in the healthy controls. TT homozygosity was found in one IRES patient (1.3%), while no TT homozygosity was found in the healthy control group. The IRES rolandic spike sources were unilateral in sixteen patients (94.1%) and were mainly located in the anterior central gyrus (58.8%). The spike source of patients without the ELP4 rs662702 T allele was correlated with the central region (p < 0.05). The rolandic spikes sources were significant correlated with the non-central gyrus (frontal and temporal lobes) in patients with the ELP4 rs662702 T allele (p < 0.05).Conclusion: The rolandic spike sources of the IRES patients with the ELP4 rs662702 T allele were significantly associated with the non-central gyrus, including the frontal and temporal lobes. Our study confirmed for the first time in vivo that ELP4 rs662702 T allele overexpression is correlated with the rolandic spike distribution in patients with IRES and provides important insights into how genetic abnormalities can lead to brain dysfunction and into the precise targeting of abnormal discharge sources in the brain.

Seizures in self-limited epilepsy with centrotemporal spikes: video-EEG documentation

Self-limited epilepsy with centrotemporal spikes, formerly called benign epilepsy with centrotemporal spikes, or rolandic epilepsy, is an age-related and well-defined epileptic syndrome. Since seizures associated with rolandic spikes are infrequent and usually occur during sleep, and repetitive or prolonged EEG recording for diagnostic purposes is not necessary for diagnosis, reports of ictal video-electroencephalographic seizures in this syndrome are rare. We aimed to show ictal video-EEG of typical rolandic seizures. We report the ictal video-EEG recordings of two children with rolandic epilepsy who presented typical rolandic seizures during routine recording. Case 1: A 9-year-old boy, with normal development, had his first seizure at 8years old, characterized by paresthesia in his left face, blocking of speech, and drooling. Carbamazepine was started with seizure control. Case 2: A 10-year-old boy, with normal development, started with focal seizures during sleep, characterized by eye and perioral deviation, and speech arrest at age of 7. He started using oxcarbazepine. Both patients underwent routine electroencephalography for electroclinical diagnosis and presented a seizure. Although self-limited epilepsy with centrotemporal spikes is a very common epileptic syndrome, seizure visualization is very difficult, and these videos may bring didactical information for recognition of this usual presentation of benign childhood focal epilepsy.

Interpretation of electroencephalography in infants

Aim: Based on published reports and our own observations, we aimed to assign the graphical elements of EEG into normal and abnormal groups and then identify up to five main graphic elements in each group to facilitate visual analysis and interpretation of EEG in young children.Materials and methods. We searched for the relevant sources in the Medline and Medscape databases using the following keywords: «neonatal EEG», «neonatal seizures», «theta burst», «delta brushes», «trace discontinue», «burst-suppression», hypsarrhythmia», etc. Our own research was conducted using an Encephalan-EEGR-19/26 encephalograph equipped with children size gold cup electrodes with a diameter of 0.6 cm. Encephalograms were recorded from 10 electrodes according to the international “10-20” system.Results and discussion. In early childhood EEGs, two large groups of EEG graphic elements can be discerned: the likely normative graphic elements and patterns of pediatric EEG (normal patterns) and the likely non-normative (abnormal) graphic elements and patterns of pediatric EEG. In the likely normative group, the main features are represented by: theta bursts, delta brushes, the “intermittent EEG curve” pattern, the occipital theta rhythm, and slow-sleep waves. In the likely non-normative group, those are: paroxysmal EEG graphic elements, asynchronous EEG patterns, spike-wave discharges, 3 Hz peak waves, hypsarrhythmia, burst-suppression pattern, rolandic occipital spikes, and a slowing rhythm pattern.Conclusion. Along with the numerous attempts to characterize the age-dependent graphic elements at an early age, there are few reports concerning older children and adults. Here we try to overcome this discrepancy by identifying two large groups of graphic elements in EEG that are similar between infants and children of an older age. Such an approach may contribute to a better understanding of normal and pathological ontogenesis.

Analysis of serial electroencephalographic predictors of seizure recurrence in Rolandic epilepsy.

We aimed to assess the relationship between electroencephalography (EEG) markers and seizure recurrence in cases with benign epilepsy with centrotemporal spikes (BECT) in a long-term follow-up study. We analyzed the data of 52 children with BECT who were divided into 2 groups: the isolated group and recurrence group. The clinical profiles and initial/serial visual EEG recordings of both groups were evaluated. The entire follow-up period ranged from 12 to 65months. None of the clinical characteristics differed between the 2 groups. Serial EEGs showed that the appearance of Rolandic spikes in the frontal region was more prevalent in the recurrence group. Moreover, a significant correlation was found between bilateral asynchronous discharges and seizure recurrence. However, on initial EEG of these patients, neither of the EEG features exhibited statistical significance. The presence of frontal focus and bilateral asynchrony appeared to be hallmarks of BECT patients with higher risk for seizure recurrence.

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

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. 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. 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). 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.

G327E mutation in SCN9A gene causes idiopathic focal epilepsy with Rolandic spikes: a case report of twin sisters

The voltage-gated sodium channel NaV1.7, encoded by the gene SCN9A, is located in peripheral neurons and plays an important role in epileptogenesis. Previous studies have identified an increasing number of SCN9A mutations in patients with variable epilepsy phenotypes. Phenotypes of SCN9A mutations include febrile seizures (FS), genetic epilepsy with febrile seizures plus (GEFS+), and Dravet syndrome (DS), which pose challenges in clinical treatment. Here, we identified a heterozygous SCN9A mutation (c.980G > A chr2:167149868 p.G327E) from two twin sisters with Rolandic epilepsy by whole-exome sequencing. The patient became seizure free with a combination of levetiracetam and clonazepam. Identification of this mutation is also helpful for advancing our understanding of the role of SCN9A in epilepsy and provides deeper insights for SCN9A mutations associated with broad clinical spectrum of seizures.

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

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. 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. 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. 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.

Algorithm for automatic EEG classification according to the epilepsy type: Benign focal childhood epilepsy and structural focal epilepsy

Abstract Rationale It is still not clear if there are EEG parameters that may be related to the epilepsy etiology in epilepsies presenting with rolandic spikes. Rolandic spikes are not pathognomonic for rolandic epilepsy and could be related to the area of discharges itself. The initial hypothesis was that even visually identical spikes have some difference, because of the different etiology. Objective The aim of the study was to find the differences in rolandic spike morphology in two epilepsy groups, different by etiology, but presenting with visually identical spikes. Methods A novel algorithm for automatic classification of interictal electroencephalogram (EEG) rolandic spikes according to the epilepsy type (Group I – patients with benign focal childhood epilepsy, self-limiting, with no causal lesion in the brain, Group II – patients with structural focal epilepsy) is proposed. The algorithm consists of three stages: 1) EEG spike detection, 2) determination of EEG spike parameters, 3) classification of EEG by epilepsy type based on estimated spike parameters. Automatic classification method is defined by artificial neural network. The algorithm has been trained and tested on a large data sample provided by Children's Hospital, Affiliate of Vilnius University Hospital Santaros Klinikos. Only those EEGs that were visually identical and inaccessible for manual clustering to the groups according the visual spike morphology and contained 50 or more spikes have been analyzed. Training and testing pools have been selected as non overlapping (containing different patients) data sets. Results The proposed methodology let us to achieve up to 75% of accuracy of classification of EEG.

Could Rolandic spikes be a prognostic factor of the neurocognitive outcome of children with BECTS?

IntroductionRolandic epilepsy, also known as benign childhood epilepsy with centrotemporal spikes (BECTS), is one of the most common epileptic syndromes in previously healthy children. Despite what was known about the benignity of this syndrome, there is always more evidence about the involvement of the cognitive functions with different deficits in several domains to be investigated. Aim of the studyThe aim of our study was to describe prognostic electroencephalogram (EEG) pattern of an adverse cognitive development to recognize patients at higher risk of lasting cognitive deficits that could need antiepileptic drugs (AEDs) or an improved neurocognitive therapy. In addition, we wanted to investigate the existence of a possible linkage between the number of interictal epileptiform discharges (IEDs) in the EEG and the more pronounced cognitive deficits. Material and methodsWe performed a case–control study on a cohort of 16 patients (10 male and 6 female) aged 4–14, diagnosed with BECTS who underwent EEG, magnetic resonance imaging (MRI), and neurocognitive assessment at the Pediatric Neurology Unit at the Umberto I Hospital, Sapienza University of Rome. Patients were divided into two groups according to the percentage of IEDs evaluated based on their sleep EEG: group A with less than 50% of the entire EEG invaded by discharges in more than 70% of the total number of EEG performed, so-called with low or intermediate activation. On the contrary, group B had a high activation, with more than 50% of the entire EEG invaded by discharges in the same percentage of the EEG performed. All children were assessed based on a protocol designed to study neuropsychological functions with specific tests chosen depending on age (Wechsler Intelligence Scale for Children IV: WISC IV; Wechsler Preschool and Primary Scale of Intelligence III: WPPSI III). Groups were compared for cognitive outcomes achieved by each patient through Student's t-test with a significance level of p<0.05 (two-tailed). ResultsThere is no statistically significant difference in the cognitive outcomes of these patients: Student's t-test showed a statistical significance (p) for each cognitive index always higher than 0.05, demonstrating that the intellectual quotient (IQ) and all other indexes analyzed (verbal comprehension index (VCI), perceptual reasoning index (PRI), working memory index (WMI), and processing speed index (PSI)) are not affected by the difference in EEG anomalies presented by our patients. Interestingly, all patients had an IQ equal to or greater than the Italian average (12 out of 16 patients showed an IQ>100), with selective drops, particularly significant in the WMI and also in the PSI. ConclusionsOur results clearly demonstrate the importance of a proper evaluation of patients with this kind of epilepsy, without paying attention only to those with the greatest number of IEDs or seizures because all of them had a neurocognitive impairment, especially in memory. These data may be reinforced by a larger sample for an even more significant statistical value. These results also highlight the importance of a neurocognitive therapy for these children to treat for their specific needs.

F82 EEG voltage display of focal epileptiform transients: Applications to correlation with gross generator anatomy

EEG voltage display for examination of focal interictal epileptiform transients (FIET) was developed to improve reliability of differentiation of EEG spikes/sharp waves (SSW) from FIET not predictive of epilepsy (Matsuo 2017, http://www.AESnet.org). Electrode array consisted of 23 head-surface placements, 19 10–20 System placements, and 2 south-hemisphere pairs, zygomatic (ZY) and mastoid (MS). Each of 23 head-surface electrodes served as common reference (CR) against 23 inputs for 529 (23 × 23) CR derivations, which were grouped by CR and reformatted into 23 polygraphic channel-overlays (PGCO). Operation of comprehensive CR replacement (PGCO-CCRR) utilized Persyst 13 edit functions. Solid angle theorem applies to interpretation of PGCO-CCRR. Objective of this study was to explore broader applications of PGCO-CCRR to examination of FIET with waveform complexity beyond 4 major SSW components (base-peak-trough-wave: B-P-T-W), as previously investigated in 121 FIET. Digital EEG sample pages (typically 10 to 20-s segment in anterior-posterior serial bipolar derivations) were reviewed and 2 groups of EEG features were sought. (1) Rare FIET suggestive of non-vertical orientation of equivalent current dipole secondary to cerebral anatomy that deviates from spherical model at major brain fissures, and (2) waveform complexity suggestive of contribution of multiple generators, commonly seen in periodic discharges (PD), particularly focal PD exhibiting traveling wave features. FIET of interest were prepared in 3 display alternatives, (1) anterior-posterior serial bipolar derivations, (2) common average reference (CAR) derivations, and (3) PGCO-CCRR. Time scale and filter settings were carefully controlled so that accuracy of cursor placement could be assured among 3 displays, when made into composite for visual inspection. Display gain was independently adjusted for best image quality. Major (B-P-T-W) and minor (notches and/or turns) FIET components identified in conventional displays were readily correlated in PGCO-CCRR. Minor latency differences could be appreciated in PGCO-CCRR by inspection alone as phase-shift, while conventional polygraphic examination required multiple latency measurements for confirmation. PGCO-CCRR provided one-step alternative for evaluation of non-vertical dipole source configuration. Some PD revealed previously noted pre-base shift (Matsuo 2012, http://www.AESnet.org). PGCO-CCRR could reliably demonstrate subtle features that are relevant for source localization and neuroanatomical correlation. PGCO-CCRR may be more reliable in EEG screening for benign epilepsy with Rolandic spikes. Inclusion of south-hemisphere electrode coverage is important. Increased temporal sampling frequency can be expected to improve display resolution, while increased spatial sampling may not, unless signal magnitude is favorable against background.

F192. Role of multimodal extra and intraoperative Stereoelectroencephalography (sEEG) monitoring in tailoring staged surgical resection in patients with eloquent cortex (Rolandic) pharmacoresistant epilepsy

Introduction To describe the feasibility, safety and seizure outcome of patients with medically intractable rolandic epilepsy(RE) who underwent staged resections guided by multimodal extra and intraoperative SEEG recordings. Methods We retrospectively studied and analyzed patients, who underwent extra and intraoperative intracranial invasive stereoEEG monitoring, data related to semiology, non-invasive electrophysiology, imaging, type of resection, complications, surgical pathology results and seizure outcome from January 2015 through September 2017, under Cleveland Clinic IRB. Results Five patients were identified as having intractable RE based on analysis of pre-surgical evaluation using 3T magnetic resonance imaging (MRI), magnetoencephalography(MEG) and positron emission tomography (PET). Preoperative magnetic resonance imaging were considered nonlesional in all five patients but after the pre-surgical evaluation, there were abnormal sulcation pattern or increased signal in white matter were noticed which are of unknown significance. All five patients were underwent sEEG implantation with hypothesis of peri-rolandic or paracentral lobule regions being epileptogenic. Extra-operative sEEG data in all patients showed ictal onset zone involving rolandic cortex (hand knob and paracentral lobule), premotor and/or supplementary motor area (SMA). In two patients, hand knob rolandic cortex was the region of interest The other three being paracentral lobule (leg motor). Given all the data (semiology, sEEG data and pre-sugical evaluation), the conclusion of epileptogenic zone (EZ) being close proximity to eloquent cortex. Given the semiology, staged resection approach with continuous sEEG recording was performed in the operating room. Resection of interictally active non-eloquent cortex electrodes was performed first guided by real-time intraoperative sEEG (electrophysiology) data. The resection was also guided by the sEEG electrode in three dimensions. Resolution of rolandic hand motor spike activities was documented after resection of SMA in three patients, cingulate and pre-motor areas in one patient. In the last patient, hand sensory area was resected sparing motor cortex. Three out of five patients did not have any deficit but two had mild foot drop. Pathology showed focal cortical dysplasia type (IB, IIA, and IIB) and a possible vascular malformation in another. All patients were reported to be seizure free at follow up period of 6–28 months. Conclusion Taken into account of hyper-synchronous connectivity in frontal and parietal rolandic regions, we present a case series of patients who underwent staged resections guided by a novel multimodal method of invasive monitoring. The results of this highly selected group of patients testify for the feasibility and safety of a novel multimodal method of invasive monitoring, combining the benefits of both intra and extra-operative SEEG recording, especially operating around the central lobule near hand knob regions.

Serial changes in the paroxysmal discharges in rolandic epilepsy may predict seizure recurrence: A retrospective 3-year follow-up study

ObjectiveThe aim of this study was to assess the electrographic criteria related to seizure recurrence and determine age-related seizure recurrence in children with rolandic epilepsy under long-term follow-up. MethodsWe retrospectively analyzed the data belonging to 109 patients with rolandic epilepsy with sufficient information regarding disease course and follow-up duration longer than 3years. Patients were divided into two categories: Group A (n: 75), comprised of “patients having fewer than four seizures”, and Group B (n: 34), the “recurrence group comprised of patients having more than four seizures in the first three months”. The number of spikes per minute during both wakefulness and sleep, the localization of spikes other than centrotemporal region, and the duration of spike–wave activity were evaluated longitudinally, with repeated electroencephalogram (EEG) recordings every 6months. ResultsThe appearance of rolandic spikes in awake EEGs tended to be more prevalent in Group B than Group A. In Group B, spike rates significantly increased in the 12 and 18months after onset whereas spike rates increased significantly only 6months after onset in Group A. Seizure recurrence is mostly seen at 6–8years, and improvement becomes evident by age 12. The mean number of paroxysmal rolandic discharges during sleep was significantly higher in the younger age groups (3–5, 6–8), and the mean number of spikes per minute significantly decreased at ages 9–11 and over 12. ConclusionOur study demonstrates that extended periods of high frequency of paroxysmal discharges, initial frontal EEG focus, and persistence of awake interictal abnormalities are highly effective in predicting seizure recurrence in patients with rolandic epilepsy (RE).

High-frequency oscillations: The state of clinical research.

Modern electroencephalographic (EEG) technology contributed to the appreciation that the EEG signal outside the classical Berger frequency band contains important information. In epilepsy, research of the past decade focused particularly on interictal high-frequency oscillations (HFOs) > 80 Hz. The first large application of HFOs was in the context of epilepsy surgery. This is now followed by other applications such as assessment of epilepsy severity and monitoring of antiepileptic therapy. This article reviews the evidence on the clinical use of HFOs in epilepsy with an emphasis on the latest developments. It highlights the growing literature on the association between HFOs and postsurgical seizure outcome. A recent meta-analysis confirmed a higher resection ratio for HFOs in seizure-free versus non-seizure-free patients. Residual HFOs in the postoperative electrocorticogram were shown to predict epilepsy surgery outcome better than preoperative HFO rates. The review further discusses the different attempts to separate physiological from epileptic HFOs, as this might increase the specificity of HFOs. As an example, analysis of sleep microstructure demonstrated a different coupling between HFOs inside and outside the epileptogenic zone. Moreover, there is increasing evidence that HFOs are useful to measure disease activity and assess treatment response using noninvasive EEG and magnetoencephalography. This approach is particularly promising in children, because they show high scalp HFO rates. HFO rates in West syndrome decrease after adrenocorticotropic hormone treatment. Presence of HFOs at the time of rolandic spikes correlates with seizure frequency. The time-consuming visual assessment of HFOs, which prevented their clinical application in the past, is now overcome by validated computer-assisted algorithms. HFO research has considerably advanced over the past decade, and use of noninvasive methods will make HFOs accessible to large numbers of patients. Prospective multicenter trials are awaited to gather information over long recording periods in large patient samples.

Ripples on rolandic spikes: A marker of epilepsy severity.

Children with rolandic spikes may or may not have seizures, ranging from benign rolandic epilepsy to severe atypical rolandic epilepsy. We investigated whether ripples (80-250 Hz), superimposed on rolandic spikes in surface electroencephalography (EEG), can differentiate between different entities. In this cohort study we analyzed the EEG studies of children with rolandic spikes without other EEG or magnetic resonance imaging (MRI) abnormalities. They were divided into the following three groups: (1) rolandic spikes but no epilepsy, (2) typical rolandic epilepsy, and (3) atypical and symptomatic rolandic epilepsy. Ripples superimposed on rolandic spikes were marked in 10 minutes of EEG, and compared to the number of seizures before the EEG. Receiver operating characteristic (ROC) curves were constructed to determine the predictive value of ripples and spikes for having epilepsy (groups 2 and 3) and for differentiating benign courses (groups 1 or 2) from atypical and symptomatic epilepsy (group 3). Ripples were also marked in the time frequency spectrum of averaged rolandic spikes. Ripples were found in 13 of 22 children. Children without epilepsy showed no ripples, except for a single child with only one ripple. The number of ripples showed a significant positive correlation with the number of seizures (ρ = 0.70, p = 0.001), whereas spikes had a borderline significant correlation (ρ = 0.43, p = 0.05). Presence of more than two ripples was a predictor for having seizures (area under the curve [AUC] 0.84), whereas spikes could not predict having seizures (AUC 0.53). More than five ripples predicted the difference between benign courses and atypical and symptomatic epilepsy (AUC 0.91, sensitivity 63%, specificity 100%). Ripples in the time frequency spectra appeared in all children and were not related to seizures. Absence of ripples on top of rolandic spikes predicts a relative benign clinical entity, whereas in the presence of several ripples, the child is likely to have more seizures than classical rolandic epilepsy, and pharmacologic treatment might be needed.

Vertex Rolandic Spikes and Central Sleep Apnea in a Newborn

Vertex Rolandic Spikes and Central Sleep Apnea in a Newborn

Mutation screening of the PRRT2 gene for benign epilepsy with centrotemporal spikes in Chinese mainland population

Proline-rich transmembrane protein 2 gene (PRRT2) mutations are reported to cause common paroxysmal neurological disorders and show a remarkable pleiotropy. Benign epilepsy with centrotemporal spikes (BECTS) is considered to be the most common epilepsy syndrome in childhood. It is placed among the idiopathic localization related epilepsies. Recently, it was reported that a girl with a PRRT2 mutation c.649_650insC developed infantile focal epilepsy with bilateral spikes which resembled the rolandic spikes. Hereby we performed a comprehensive genetic mutation screening of PRRT2 gene in a cohort of 53 sporadic BECTS patients. None of the 53 sporadic BECTS patients and other 250 controls carried mutations including c.649_650insC in PRRT2. Our data indicated that the PRRT2 mutations might most likely not be associated with BECTS in Chinese mainland population.

Real-time effects of centrotemporal spikes on cognition in rolandic epilepsy: An EEG-fMRI study.

To identify the real-time effects of interictal rolandic spikes (or centrotemporal spikes [CTS]) on language, behavior, and cognitive function in patients with rolandic epilepsy (RE). We studied 22 medication-naive patients with RE using EEG-fMRI with a 3T MRI scanner. We used simultaneous EEG to define the pre-CTS, CTS, and post-CTS periods. We analyzed the dynamic functional connectivity maps of the rolandic network during the 3 interictal CTS periods. The analysis of dynamic changes revealed positive correlations between the bilateral rolandic areas and the left inferior frontal gyrus (IFG; Broca area), the left inferior parietal lobe and the supramarginal gyrus (areas responsible for receptive language function), and the right IFG and left caudate. Anti-correlations were found in the default mode network (bilateral superior frontal gyrus, left middle frontal gyrus, left middle temporal gyrus, and right precuneus). Interictal CTS directly disrupts the functional brain networks responsible for language, behavior, and cognition in children with typical RE. It is important to suppress discharges to reduce the risk of neuropsychological impairments in children with RE.

Increased resting-state EEG functional connectivity in benign childhood epilepsy with centro-temporal spikes

PurposeTo explore intrahemispheric, cortico-cortical EEG functional connectivity (EEGfC) in benign childhood epilepsy with rolandic spikes (BECTS). Methods21-channel EEG was recorded in 17 non-medicated BECTS children and 19 healthy controls. 180s of spike- and artifact-free activity was selected for EEGfC analysis. Correlation of Low Resolution Electromagnetic Tomography- (LORETA-) defined current source density time series were computed between two cortical areas (region of interest, ROI). Analyses were based on broad-band EEGfC results. Groups were compared by statistical parametric network (SPN) method. Statistically significant differences between group EEGfC values were emphasized at p<0.05 corrected for multiple comparison by local false discovery rate (FDR). Results(1) Bilaterally increased beta EEGfC occurred in the BECTS group as compared to the controls. Greatest beta abnormality emerged between frontal and frontal, as well as frontal and temporal ROIs. (2) Locally increased EEGfC emerged in all frequency bands in the right parietal area. ConclusionsAreas of increased EEGfC topographically correspond to cortical areas that, based on relevant literature, are related to speech and attention deficit in BECTS children.