Seizures are usually brief, lasting for 1 to 3 minutes, and their clinical manifestations include (see Video 1):

Generalized convulsive status epilepticus is rare. Opercular status epilepticus occurs in atypical evolutions of BECTS or, exceptionally, it may be induced by carbamazepine.²³ This status may last for hours to months and consists of continuous unilateral or bilateral contractions of the mouth, tongue, or eyelids, positive or negative subtle perioral or other myoclonia, dysarthria, anarthria, or speech arrest, buccofacial apraxia and hypersalivation.²⁴

The interictal EEG is distinctive in BECTS, showing centrotemporal spike-and-wave discharges which have a tangential dipole that is negative in the centrotemporal area and positive frontally. Centrotemporal spikes (CTS) are the hallmark of the BECTS syndrome and are mainly localized in the left central (C3) and right central (C4) or the supra-sylvian electrodes (C5, C6 using the International 10-10 system of electrode placement) and not in the temporal ones.²⁵ CTS are markedly activated by drowsiness, occur independently over both hemispheres at frequencies of 4 to 20 discharges per minute, and usually occur in clusters (Fig. 1). Recent studies show that the main negative spike component is modeled by a stable tangential dipole source, with the positive pole was maximum in the frontal region, while the negative pole was maximum in the central region.²⁶ The main spike (sharp wave) component is diphasic with a maximum surface, negative, rounded peak that is followed by a smaller positive peak. The amplitude of the main spike component often exceeds 200 μV, though it may be much smaller or much higher. The negative phase is larger than the positive phase of the spike, as well as the preceding or following components of the spike-slow wave complex. About 4% of patients with rolandic epilepsy also show brief bursts of 3-5 Hz slow waves with internalized small spikes lasting 1-3 seconds, without overt clinical symptoms.²⁷ The frequency, location and persistence of CTS are not specific for BECTS.^27,28 In fact, they occur in 2-3% of normal school-aged children, of whom less than 10% develop rolandic seizures.¹⁶ They are also seen in children with other organic brain diseases with or without seizures^27–29 as well as in non-epileptic children with symptoms such as headaches, and speech, behavioral, or learning difficulties.

Fig. 1 Example of EEG tracing of a patient with rolandic epilepsy with typical spikes in the left fronto-centrotemporal area with spreading in the right corresponding area (arrows).

Somatosensory stimulation activates CTS in 10% to 20% of cases and evokes giant somatosensory evoked spikes (GSES) that, like spontaneous CTS, appear in children with or without seizures and disappear with age.^27,30,31 Generalized tonic-clonic seizures (GTCS), in BECTS are preceded by focal clinical and EEG features.^27,32

Twin studies³³ suggest the existence of a genetic basis for BECTS. Specifically, there is a proven linkage with chromosome 15q14.³⁴ Even if there was an early hypothesis of an autosomal inheritance pattern, later studies suggested a multifactorial inheritance; more recent work has shown that noninherited factors are more important than once believed.³⁵

The seizures occur during sleep, mostly night sleep but also during daytime sleep, in approximately 75% of the affected children, and usually appear after the child falls asleep or close to the wake-up time. Although the rolandic seizures occur mainly during sleep, studies on sleep in patients with BECTS are rare. One of the first studies on this topic³⁶ showed that no specific or clear-cut pathologic alterations of sleep were found. The authors concluded that epileptic malfunctioning of neuronal aggregates does not affect sleep organization and that the lack of detrimental interactions between epilepsy and sleep in this group may be related to the benign course of BECTS. The same authors showed a clear increase in spike activity in the first cycle of sleep and another increase near the end of night sleep. These periods of sleep correspond to the periods favored by seizures in BECTS. The level of spike activation (ie, spike density) decreased across the night: peak of activation in the first sleep cycle, followed by a marked decrease in the second cycle, especially during NREM 3 sleep and an increase in the third sleep cycle mostly related to NREM 1 and 2.³⁷

Nobili and colleagues³⁸ found a highly significant correlation between IED and sigma (12-16 Hz) activity; the IED in BECTS patients during sleep are sensitive to the IED-promoting action of the spindle-generating mechanism, while delta activity does not seem to play a facilitating role or is even inversely correlated with IED distribution.^38–40

Recently, Bruni and colleagues⁴¹ studied sleep architecture in children with BECTS, analyzing conventional sleep parameters and microstructure using cyclic alternating pattern (CAP).

In agreement with previous studies,^37,38 they confirmed that sleep architecture is not significantly altered in patients with BECTS with only mild decreases in total sleep time, sleep efficiency, and REM sleep percentage and the presence of the IEDs does not seem to alter sleep structure. However, CAP analysis of sleep microstructure in the subjects with BECTS compared with normal age-matched controls showed a reduced total NREM 2 CAP rate and reduced EEG slow oscillations during stages NREM 1 and 2 sleep. In BECTS there might be a reduction of CAP rate and a decrease of the CAP A phases, with special effect on the slow-wave containing A1 subtypes. This microstructural analysis reveals, therefore, a decrease of NREM instability, mainly in sleep stage 2.

In order to better understand these findings, one has to take into account the results of the EEG spectral analysis carried out in different types of benign epilepsies.^38,42 Data derived from spectral analysis highlight a strong correlation between the temporal distribution of CTS and that of the sigma activity, the frequency band to which spindles contribute most. The facilitating influence of sigma activity on the activation of spike activity during sleep has been found in many epilepsies of childhood that seem to be characterized by a strong NREM sleep spike activation. Spindle-related spike activation is present in functional partial epilepsies, such as BECTS,⁴³ benign epilepsy with occipital paroxysms,³⁹ lesional and cryptogenetic partial epilepsies with strong activation of epileptic discharges during sleep,³⁸ the Landau-Kleffner syndrome,⁴⁰ and the fragile-X syndrome.⁴⁴ Nobili and colleagues⁴³ also stated that, taking into account that sigma activity reflects the intra-night dynamics of sleep spindles, the neural mechanisms involved in the generation of sleep spindles might also facilitate the production of CTS. Sleep spindles are associated with sleep-protecting mechanisms and are considered to be microstates gating the sensory input toward the cortex in an inhibitory way⁴⁵ and, therefore, inhibiting slow oscillations and arousals.⁴⁶

Therefore, since CTS and spindles are strictly interdependent, and taking into account the inhibitory action of spindle activity on arousals, it can be supposed that the decrease of oscillations and of arousal-related transient events (reduction of A1 and A2 index in NREM 2), might be related to the CTS typically present in BECTS. Although this remains speculative, based on previous studies and to better clarify the relationships between sleep microstructure and spike activity, it has been shown that CAP rate decrease in NREM 2 was more evident in patients with BECTS who also showed an increase of spike density in NREM 2 versus NREM 3. This decrease was mainly related to the A1 component of CAP rate, as the A1 index was significantly lower during NREM 2. To summarize, there is a spindle-related spike activation in BECTS, and the decrease of CAP rate, EEG slow oscillations and arousals may be linked with the inhibitory action of sleep spindle activity and spikes on arousals.

An increase of the age-related, area-specific cortical excitability has been hypothesized to be at the basis of the origin of BECTS.^31,47,48 This increased excitability of the cortex is able to transform the thalamic volley that normally induces sleep spindles in a mechanism inducing epileptic discharges, as shown in animals^49,50 and in humans.⁵¹ Due to the age-related regional hyperexcitability, the cortex could react with spikes to the thalamocortical volleys that generate spindles, even in physiologic conditions in predisposed children. This hypothetical transformation of spindles into spike activity might explain the strict relationships between sigma activity and CTS but might also account for the particular sleep microstructure with spike activity independent from CAP phase A and the increase of CTS during non-CAP (NCAP).

Remission in BECTS usually occurs 2–4 years after the onset and typically before the age of 16 years. Most patients have less than a total of 10 lifetime seizures, 10–20% have just a single seizure, and about 10–20% may have frequent seizures that also remit with age.

In the past 10 years, several studies have indicated that patients with BECTS have a variety of cognitive disturbances, including language impairment, memory dysfunction, and auditory processing difficulties; this indicates that BECTS is not benign with respect to cognitive consequences.

During the active phase of the BECTS syndrome, the children may develop mild linguistic, cognitive, and behavioral abnormalities^52–55 which may be worse in those in whom the epilepsy syndrome begins at 8 years of age and/or in those with a high rate of seizure and multifocal EEG spikes.^56,57 Deonna and colleagues² showed that children with BECTS presented mild, varied, and transient cognitive difficulties during the course of their epilepsy, and in most cases this probably had a direct relation with the paroxysmal EEG activity.

A case-control study of families affected by BECTS indicates that family members of the proband who have not had seizures, demonstrate reading disabilities and speech sound disorders.⁵⁸ The families of the probands were not studied with EEG so it is unclear whether the spike-wave discharges were present in the 55% who manifested the disabilities. Assuming that BECTS is a autosomal dominant trait and would be expected to be present in 50% of family members, this study suggests that most or all of the individuals with the trait may express the disabilities.

Recently, Sarco and colleagues⁵⁹ revealed an association between mood disorder (anxiety, depression, aggression, and conduct problems) and spike frequency in BECTS: increased epileptic activity in children with BECTS may predict higher rates of mood and behavioral problems.

Panayiotopoulos syndrome (PS), otherwise defined as susceptibility to early-onset benign childhood seizures with mainly autonomic symptoms, is a common childhood epileptic syndrome with benign age-related focal seizures occurring in early and mid-childhood. After BECTS, this is the most frequent epilepsy syndrome of childhood with a mild female preponderance.

The prevalence of PS may be high, probably affecting approximately13% of children 3-6 years old with one or more nonfebrile seizures and 6% of the age group from 1 to 15 years.⁶⁰

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