Benign epilepsy of childhood with centrotemporal spikes and unilateral developmental opercular dysplasia

The case of a 15-year-old right-handed girl with developmental delay, mild retardation, astereognosis, and tactile discrimination impairment in the left arm, is reported. During sleep, right partial simple motor seizures with sialorrhea and saliva pooling were present, sometimes followed by secondary generalization. Absences and drop attacks were also observed. Electroencephalography revealed left centrotemporal spike waves spreading to the homologous contralateral region, generalized 3-Hz spike-and-wave complexes enhanced by hyperventilation, and generalized polyspike-and-wave discharges during drowsiness. Magnetic resonance imaging showed right perisylvian (opercular) malformation. Benign epilepsy of childhood with centrotemporal spikes (BECCTS) is a focal idiopathic epilepsy presumed to be of genetic origin. Although brain damage is not expected, structural lesions including opercular macrogyria have been reported. This coexistence has been considered mainly casual and only exceptionally causal. The Foix-Chavany-Marie syndrome or operculum syndrome is the result of bilateral opercular damage. In our child the right structural and the left functional lesions appeared mutually activated, yielding a transient opercular syndrome. The concomitance of BECCTS and developmental opercular dysplasia is suggestive of a common genetic substratum.     

Suspected herpes encephalitis and opercular syndrome in childhood

Herpes simplex encephalitis is the most common form of sporadic viral encephalitis. It may occur at any age, giving rise to a syndrome with a high morbidity and mortality. Its presentation may be atypical, and the initial complementary investigations nonspecific, making early diagnosis difficult and thus worsening its prognosis. This report describes four infants with herpes encephalitis presenting with an opercular syndrome that left significant sequelae after the acute episode. The opercular syndrome is characterized clinically by a disturbance of voluntary control of the facio-linguo-glosso-pharyngeal muscles, affecting speech and swallowing. Recognition of the opercular syndrome as a form of presentation of herpes encephalitis enables early diagnosis to be made in these patients, with the rapid initiation of treatment with acyclovir, improving the clinical course.     

Bilateral opercular polymicrogyria

Foix-Chavany-Marie syndrome (FCMS), or faciopharyngoglossomasticatory diplegia, is an uncommon syndrome that can result from vascular or developmental lesions of the anterior opercula bilaterally. We report the first pathological documentation of the developmental form of this disorder. Pathological examination revealed bilateral failure of opercular closure, opercular polymicrogyria, periventricular gray-matter heterotopias, and absence of the septum pellucidum.     

Transient opercular syndrome: a manifestation of uncontrolled epileptic activity

Newly appearing oral motor apraxia should alert physicians to the possibility of an organic lesion in the operculum, the perisylvanian cortex. A 6 1/2-year-old boy who is being followed for complex partial seizures with secondary generalization failed to respond to carbamazepine and then to the addition of sodium valproate. The further addition of lamotrigine stopped the seizures but the patient presented with a new onset of opercular syndrome, manifested by severe oral motor apraxia with difficulties in chewing and swallowing and speech. MRI study of the brain revealed no abnormalities. The opercular syndrome resolved completely when the lamotrigine was replaced with phenobarbital, and did not recur during the follow-up period of 2 years. The EEG, however, continued to be abnormal. We conclude that opercular syndrome may be a manifestation of abnormal localized electrical activity at the operculum, even in the absence of an organic lesion on imaging studies, and it may be a marker for an epilepsy which is not easily controlled.     

Role of the corpus callosum in the somatosensory activation of the ipsilateral cerebral cortex: an fMRI study of callosotomized patients

To verify whether the activation of the posterior parietal and parietal opercular cortices to tactile stimulation of the ipsilateral hand is mediated by the corpus callosum, a functional magnetic resonance imaging (fMRI, 1.0 tesla) study was performed in 12 control and 12 callosotomized subjects (three with total and nine with partial resection). Eleven patients were also submitted to the tactile naming test. In all subjects, unilateral tactile stimulation provoked a signal increase temporally correlated with the stimulus in three cortical regions of the contralateral hemisphere. One corresponded to the first somatosensory area, the second was in the posterior parietal cortex, and the third in the parietal opercular cortex. In controls, activation was also observed in the ipsilateral posterior parietal and parietal opercular cortices, in regions anatomically corresponding to those activated contralaterally. In callosotomized subjects, activation in the ipsilateral hemisphere was observed only in two patients with splenium and posterior body intact. These two patients and another four with the entire splenium and variable portions of the posterior body unsectioned named objects explored with the right and left hand without errors. This ability was impaired in the other patients. The present physiological and anatomical data indicate that in humans activation of the posterior parietal and parietal opercular cortices in the hemisphere ipsilateral to the stimulated hand is mediated by the corpus callosum, and that the commissural fibres involved probably cross the midline in the posterior third of its body.     

Pena-Shokeir phenotype associated with bilateral opercular polymicrogyria

Autopsy examination of an infant with the Pena-Shokeir phenotype revealed bilateral opercular polymicrogyria associated with neuronal loss and ferrugination in the basal ganglia, thalamus, brainstem, and spinal anterior horns. Bilateral opercular polymicrogyria previously has been linked to the developmental form of Foix-Chavany-Marie syndrome, or faciopharyngoglossomasticatory diplegia. In the Pena-Shokeir phenotype, bilateral opercular polymicrogyria may contribute to deficits in swallowing and facial movements. The pattern of brain and spinal cord injury in this case supports previous suggestions that the Pena-Shokeir phenotype (and certain other forms of arthrogryposis multiplex congenita) may be caused by hypoxic-ischemic injury to the developing central nervous system.     

Cortical connections of the frontoparietal opercular areas in the Rhesus monkey

The connections of the frontoparietal opercular areas were studied in rhesus monkeys by using antero- and retrograde tracer techniques. The rostral opercular cortex including the gustatory and proisocortical motor (ProM) areas is connected with precentral areas 3, 1, and 2 as well as with the rostral portion of the opercular area which resembles the second somatosensory type of cortex (area SII) and the ventral portion of area 6. Its distant connections are with the ventral portion of prefrontal areas 46, 11, 12, and 13 as well as with the rostral insula and cingulate motor area (CMAr). The mid opercular region (areas 1 and 2) is connected with pre- and postcentral areas 3, 1, and 2 as well as SII. Additionally, it is connected with the ventral portion of area 6, area 44, area ProM, the gustatory area, and the rostral insula. Its distant connections are with area 4, the ventral portion of area 46, area 7b, and area POa in the intraparietal sulcus (IPS). The rostral parietal opercular region is connected with the postcentral portions of areas 3, 1, and 2; areas 5, 7, and SII; the gustatory area; and the vestibular area. Its other connections are with area 4, area 44, the ventral portion of area 46, area ProM, CMAr, and the supplementary motor area (SMA). The caudal opercular region is connected with the dorsal portion of area 3; areas 2, 5, and 7a; and areas PEa as well as IPd of IPS. It is also connected with area SII, insula, and the superior temporal sulcus. Its distant connections are with area 44; the dorsal portion of area 8 and the ventral portion of area 46; as well as CMAr, SMA, and the supplementary sensory area. This connectivity suggests that the ventral somatosensory areas are involved in sensorimotor activities mainly related to head, neck, and face structures as well as to taste. Additionally, these areas may have a role in frontal (working) and temporal (tactile) memory systems. J. Comp. Neurol. 403:431–458, 1999. © 1999 Wiley-Liss, Inc.     

Childhood acute disseminated encephalomyelitis presenting as Foix-Chavany-Marie syndrome

A 10-year-old boy presented with anarthria and bilateral central faciolinguovelopharyngeomasticatory paralysis with "automatic voluntary dissociation" suggestive of Foix-Chavany-Marie syndrome or anterior opercular syndrome following a nonspecific upper respiratory infection. Brain magnetic resonance imaging revealed bilateral subcortical perisylvian demyelination in addition to multiple subcortical white-matter demyelination. The clinicoradiologic picture suggested acute disseminated encephalomyelitis. The child recovered completely following intravenous methylprednisolone and intravenous immunoglobulin therapy. This is the first report of anterior opercular syndrome in childhood acute disseminated encephalomyelitis.     

Transient epileptic opercular syndrome.

Ictal transient opercular syndrome is rarely observed in benign epilepsy with centro-temporal spikes in children, and even more rarely in epilepsia partialis continua and symptomatic focal status epilepticus in adults. Here we report the ictal and interictal neuroimaging and electrophysiological findings in an adult female suffering from discontinuous focal status epilepticus presenting as a transient opercular syndrome. This patient was unusual insofar as the discharges were strictly unilateral, i.e., that even with extensive neuroimaging no structural abnormalities could be found.     

Opercular reflex seizures: a case report with stereo-electroencephalographic demonstration.

Reflex epileptic seizures of opercular origin have been described previously based on video-electroencephalographic monitoring, but very few patients have been explored with depth electrodes. We report a woman with late-onset epilepsy who had intractable seizures despite trials of several antiepileptic drugs. At the time of the depth-electrode recordings, seizures were usually continuous and occurred either spontaneously or were induced by movements of the jaw and mouth. The seizures originated in the deep central opercular cortex; localization was confirmed by a good surgical outcome.     

Simultaneous video analysis of the kinematics of opercular movement and electromyographic activity during agonistic display in Siamese fighting fish.

Neuroethology seeks to uncover the neural mechanisms underlying natural behaviour. One of the major challenges in this field is the need to correlate directly neural activity and behavioural output. In most cases, recording of neural activity in freely moving animals is extremely difficult. However, electromyographic recording can often be used in lieu of neural recording to gain an understanding of the motor output program underlying a well-defined behaviour. Electromyographic recording is less invasive than most other recording methods, and does not impede the performance of most natural tasks. Using the opercular display of the Siamese fighting fish as a model, we developed a protocol for correlating directly electromyographic activity and kinematics of opercular movement: electromyographic activity was recorded in the audio channel of a video cassette recorder while video taping the display behaviour. By combining computer-assisted, quantitative video analysis and spike analysis, the kinematics of opercular movement are linked to the motor output program. Since the muscle that mediates opercular abduction in this fish, the dilator operculi, is a relatively small muscle with several subdivisions, we also describe methods for recording from small muscles and marking the precise recording site with electrolytic corrosion. The protocol described here is applicable to studies of a variety of natural behaviour that can be performed in a relatively confined space. It is also useful for analyzing complex or rapidly changing behaviour in which a precise correlation between kinematics and electromyography is required.     

Distal myopathy with rimmed vacuoles in a case of opercular syndrome

We report the case of a 30-year-old man with opercular syndrome who developed distal myopathy with rimmed vacuoles (DMRV). Muscle biopsy showed variation in fiber size and scattered fibers with rimmed vacuoles. The identification of a homozygous c. 1714G>C (p. V572L) mutation in the GNE gene genetically confirmed the diagnosis of DMRV, which is thought to be identical to hereditary inclusion body myopathy (HIBM). Our results indicate the possibility that other organs such as the central nervous system could be affected in DMRV/HIBM, although bilateral opercular lesions might have been caused by destructive events either in utero or in the perinatal period.     

Developmental Foix-Chavany-Marie syndrome in identical twins

Foix, Chavany, and Marie described a syndrome of faciopharyngoglossomasticatory diplegia resulting from bilateral anterior opercular infarction. We describe identical twins who have a developmental form of the syndrome. The twins, aged 41 years, were the product of a normal pregnancy and birth, but had subsequent delayed motor milestones, seizures, poor language development, mild mental retardation, drooling, absent gag reflexes, inability to protrude the tongue, brisk jaw jerks, impaired fine finger movements, symmetrical brisk reflexes, flexor plantar responses, and mildly spastic gait. Magnetic resonance imaging showed bilateral perisylvian cortical dysplasia compatible with polymicrogyria and incomplete opercular formation.     

Akathisia in association with herpes simplex encephalitis relapse and opercular syndrome in children

We report a 2-year-old boy with herpes simplex virus type 1 encephalitis (HSE) and opercular syndrome who presented with clinical relapse characterized by chorea-like involuntary movements that suggest akathisia. The patient initially presented with multiple focal seizures that cause epilepsia partialis continua, polymerase chain reaction (PCR) for herpes simplex virus type 1 was positive. He developed hypersalivation, speech and swallowing difficulties within 30 days. Based on these findings the patient was diagnosed as having opercular syndrome due to HSE. He developed akathisia on 44th day of admission as a relapse and he was successfully treated with propranolol.     

Altered brain function in persistent postural perceptual dizziness: A study on resting state functional connectivity

This study used resting state functional magnetic resonance imaging (rsfMRI) to investigate whole brain networks in patients with persistent postural perceptual dizziness (PPPD). We compared rsfMRI data from 38 patients with PPPD and 38 healthy controls using whole brain and region of interest analyses. We examined correlations among connectivity and clinical variables and tested the ability of a machine learning algorithm to classify subjects using rsfMRI results. Patients with PPPD showed: (a) increased connectivity of subcallosal cortex with left superior lateral occipital cortex and left middle frontal gyrus, (b) decreased connectivity of left hippocampus with bilateral central opercular cortices, left posterior opercular cortex, right insular cortex and cerebellum, and (c) decreased connectivity between right nucleus accumbens and anterior left temporal fusiform cortex. After controlling for anxiety and depression as covariates, patients with PPPD still showed decreased connectivity between left hippocampus and right inferior frontal gyrus, bilateral temporal lobes, bilateral insular cortices, bilateral central opercular cortex, left parietal opercular cortex, bilateral occipital lobes and cerebellum (bilateral lobules VI and V, and left I–IV). Dizziness handicap, anxiety, and depression correlated with connectivity in clinically meaningful brain regions. The machine learning algorithm correctly classified patients and controls with a sensitivity of 78.4%, specificity of 76.9%, and area under the curve = 0.88 using 11 connectivity parameters. Patients with PPPD showed reduced connectivity among the areas involved in multisensory vestibular processing and spatial cognition, but increased connectivity in networks linking visual and emotional processing. Connectivity patterns may become an imaging biomarker of PPPD.     

Insular-opercular seizures manifesting with sleep-related paroxysmal motor behaviors: a stereo-EEG study

Purpose: Sleep‐related complex motor seizures are a common feature of nocturnal frontal lobe epilepsy. Nevertheless, recent studies also suggest that sleep‐related hypermotor seizures can originate in the insula. The present study describes the electroclinical features of eight drug‐resistant epileptic patients with insular‐opercular seizures manifesting with nocturnal complex motor seizures. Methods: Patients underwent a comprehensive presurgical evaluation, which included history, interictal electroencephalography (EEG), scalp video‐EEG monitoring, high‐resolution magnetic resonance imaging (MRI), and intracerebral recording by stereo‐EEG. Key Findings: Almost all patients reported an initial sensation consisting of viscerosensitive or somatosensory symptoms. Ictal clinical signs were represented by tonic–dystonic asymmetric posturing and/or hyperkinetic automatisms, including bimanual/bipedal activity and ballistic movements. Some patients exhibited dysarthric speech, hypersalivation, and apnea. Interictal and ictal EEG provided lateralizing information in the majority of patients. In three patients, MRI showed a focal anatomical abnormality in the insular‐opercular region. Stereo‐EEG ictal recordings demonstrated that the epileptic discharge involved simultaneously the insular cortex and the opercular region. Complex motor manifestations appeared when the ictal discharge showed an extrainsular spreading to frontomesial regions (cingulum, superior frontal gyrus, and supplementary motor area) and/or to internal and neocortical temporal lobe structures. Six patients received an insular‐opercular cortical resection; three of them are seizure free (minimum follow‐up 24 months) and in one a marked reduction in seizure frequency was obtained. Two patients have been operated on recently. Histology revealed a focal cortical dysplasia in three patients. One patient excluded from surgery died for sudden unexpected death in epilepsy during sleep. Significance: Our data strengthen the concept that sleep‐related complex motor attacks can originate in the insula, and provide useful electroclinical information to differentiate this localization from those with similar clinical characteristics. Furthermore, this study indicates that in these drug‐resistant patients, surgical treatment represents a highly effective treatment option.     

Distinct fronto-central N60 and supra-sylvian N70 middle-latency components of the median nerve SEPs as assessed by scalp topographic analysis, dipolar source modelling and depth recordings.

OBJECTIVES: To investigate the possible contribution of the second somatosensory (SII) area in the generation of the N60 somatosensory evoked potential (SEP).METHODS: In 7 epileptic patients and in 6 healthy subjects scalp SEPs were recorded by 19 electrodes placed according to the 10-20 system. All epileptic patients but one were also investigated using depth electrodes chronically implanted in the parieto-rolandic opercular cortex. Scalp SEPs underwent brain electrical source analysis.RESULTS: In both epileptic patients and healthy subjects, scalp recordings showed two middle-latency components clearly distinguishable on the basis of latency and scalp distribution: a fronto-central N60 potential contralateral to stimulation and a later bilateral temporal N70 response. SEP dipolar source modelling showed that a contralateral perisylvian dipole was activated in the scalp N70 latency range whereas separate perirolandic and frontal sources were activated at the scalp N60 latency. Depth electrodes recorded a biphasic N60/P90 response in the parieto-rolandic opercular regions contra- and ipsilateral to stimulation.CONCLUSIONS: Two different middle-latency SEP components N60 and N70 can be distinguished by topographic analysis and source modelling of scalp recordings, the sources of which are located in the fronto-central cortex contralateral to stimulation and in the supra-sylvian cortex on both sides, respectively. The source location of the scalp N70 in the SII area is strongly supported by its spatio-temporal similarities with SEPs directly recorded in the supra-sylvian opercular cortex.     

Two cases of opercular myoclonic‐anarthric status epilepticus

Opercular myoclonic‐anarthric status epilepticus (OMASE) is a rare form of epilepsia partialis continua presenting as fluctuating dysarthria, or even anarthria. The condition is caused by an epileptogenic lesion involving the opercular cortex of either hemisphere. Speech impairment is secondary to bilateral epileptic activity affecting the glossopharyngeal muscles. This bilateral nature of the condition is due to the fact that innervation of cranial nerves V, VII, IX, X and XII from the opercular area of the primary motor cortex is bilateral. The aetiology of the condition varies, and includes vascular lesions, tumours, and encephalitis, among other causes. A low threshold for clinical suspicion is necessary in order to ensure the timely initiation of antiepileptic treatment, thereby preventing the condition from becoming drug resistant. We present two cases of OMASE which differ in terms of aetiology, clinical course, and treatment response. [Published with video sequences on www.epilepticdisorders.com ].     

Brain generators of laser-evoked potentials: from dipoles to functional significance

In this work we review data on cortical generators of laser-evoked potentials (LEPs) in humans, as inferred from dipolar modelling of scalp EEG/MEG results, as well as from intracranial data recorded with subdural grids or intracortical electrodes. The cortical regions most consistently tagged as sources of scalp LERs are the suprasylvian region (parietal operculum, SII) and the anterior cingulate cortex (ACC). Variability in opercular sources across studies appear mainly in the anterior-posterior direction, where sources tend to follow the axis of the Sylvian fissure. As compared with parasylvian activation described in functional pain imaging studies, LEP opercular sources tended to cluster at more superior sites and not to involve the insula. The existence of suprasylvian opercular LEPs has been confirmed by both epicortical (subdural) and intracortical recordings. In dipole-modelling studies, these sources appear to become active less than 150 ms post-stimulus, and remain in action for longer than opercular responses recorded intracortically, thus suggesting that modelled opercular dipoles reflect a "lumped" activation of several sources in the suprasylvian region, including both the operculum and the insula. Participation of SI sources to explain LEP scalp distribution remains controversial, but evidence is emerging that both SI and opercular sources may be concomitantly activated by laser pulses, with very similar time courses. Should these data be confirmed, it would suggest that a parallel processing in SI and SII has remained functional in humans for noxious inputs, whereas hierarchical processing from SI toward SII has emerged for other somatosensory sub-modalities. The ACC has been described as a source of LEPs by virtually all EEG studies so far, with activation times roughly corresponding to scalp P2. Activation is generally confined to area 24 in the caudal ACC, and has been confirmed by subdural and intracortical recordings. The inability of most MEG studies to disclose such ACC activity may be due to the radial orientation of ACC currents relative to scalp. ACC dipole sources have been consistently located between the VAC and VPC lines of Talairach's space, near to the cingulate subsections activated by motor tasks involving control of the hand. Together with the fact that scalp activities at this latency are very sensitive to arousal and attention, this supports the hypothesis that laser-evoked ACC activity may underlie orienting reactions tightly coupled with limb withdrawal (or control of withdrawal). With much less consistency than the above-mentioned areas, posterior parietal, medial temporal and anterior insular regions have been occasionally tagged as possible contributors to LEPs. Dipoles ascribed to medial temporal lobe may be in some cases re-interpreted as being located at or near the insular cortex. This would make sense as the insular region has been shown to respond to thermal pain stimuli in both functional imaging and intracranial EEG studies.     

Unusual Case of Presenile Dementia–A Clinical Case Report

Abstract: A predominant disturbance of expressive language function was the first and outstanding manifestation of presenile dementia in a 40-year-old female. A CT-scan revealed a moderate atrophy in the frontal, triangular and opercular regions. This is an unusual case of presenile dementia with an aphasic disturbance of language as the initial symptom.