Symptoms in focal sensory seizures. Clinical and electroencephalographic features.

PURPOSE: Aura is a brief subjective symptom that may represent the initial manifestation of a partial epileptic seizure with objective signs or constitute the entire epileptic attack (focal sensory seizure (FSS)). We studied the electro-clinical features of FSSs recorded in 28 patients. METHODS: Using long-term surface video-EEG recordings, we examined 28 patients (from a consecutive series of 64) with stereotyped FSSs and complex partial seizures (CPS) preceded in at least one instance by identical subjective manifestations (overall 255 FSSs and 39 CPS were recorded). FSSs were subdivided according to the type of sensation into somatosensory, visual or oculosensory, viscerosensory, experiential, cephalic and diffuse warm sensations. The EEG discharges accompanying FSSs were examined by two of the authors either blinded as to the type and timing of the seizure, or unblinded, i.e. after receiving complete clinical information including timing of the patient's warning. RESULTS: The ictal pattern accompanying FSSs was identified blind in 13 patients and unblind in 8 patients. In seven patients, the ictal discharge remained undetected. In the cases with recognizable ictal abnormalities, two main patterns could be distinguished, static and dynamic. FSSs whose ictal discharge could be recognized by blind EEG examination more frequently consisted of somatosensory and visual or oculosensory manifestations, and the discharge generally involved the centro-parieto-occipital regions. The ictal discharge of viscerosensory and experiential FSSs more easily remained undetected; when identified, it generally involved the fronto-temporal regions. CONCLUSIONS: FSSs are often accompanied by ictal abnormalities recognizable on surface EEG. A thorough knowledge of their EEG accompaniments may be a useful diagnostic aid in patients with partial epilepsy.     

Benign focal seizures of adolescence: a prospective study

PURPOSE: To characterize the clinical and EEG findings and evolution of the syndrome of benign focal seizures of adolescence (BFSA), as described by Loiseau et al. METHODS: A prospective study was performed in adolescents with normal clinical and neurologic examinations and normal neuroradiologic studies who had focal seizures that occurred isolated or in a cluster, with or without secondary generalization in the first 24 to 48 h after onset. None of the patients was treated with antiepileptic drugs (AEDs). RESULTS: Between January 1996 and January 2002, 15 patients with BFSA were enrolled in the study. Median age at onset of BFSA was 14 years. Thirteen patients had focal sensory or motor seizures. In two patients, the ictal manifestation was motion arrest associated with oral automatisms. Eight of them evolved to generalized tonic-clonic seizures. Thirteen patients had seizures only when awake, and the other two, both when awake and during sleep. Repeated interictal EEGs were normal, but in four of the patients who had seizures in a cluster, we were able to record an EEG within 8 h after seizure onset. Two of these four patients had focal seizures, and their waking EEG showed focal centroparietal theta activities. The other two patients had secondarily generalized seizures, and their waking EEG showed bilateral theta activities instead. Prognosis was excellent. CONCLUSIONS: BFSA is a well-defined seizure syndrome, recognizable by clinical and EEG features, as described by Loiseau et al. In teenagers with these electroclinical features with a normal neurologic examination and normal neuroradiologic findings, AEDs should be avoided.     

Ictal SPECT in supplementary motor area seizures

OBJECTIVES: We used ictal single photon emission computed tomography (SPECT) to clarify the propagation pathways of epileptic discharges in patients with supplementary motor area (SMA) seizure. METHODS: In four patients (four males, age range, 18-27 years) with SMA seizures, SPECT studies by radioisotope 99mTc-ECD were performed as a preoperative evaluation. Two of the patients remained seizure-free after complete resection of the focal cortical dysplasia on magnetic resonance (MR) images including epileptic foci. In the other two patients, MR images were normal, but subdural electrode monitoring allowed for verifying the ictal onset in the left SMA. After partial resection of the SMA including epileptic foci, these patients experienced a significant (>90%) reduction of seizure frequency. Regional cerebral blood flow (rCBF) measurements obtained under ictal and interictal conditions were compared on a voxel-by-voxel basis by means of the SPM99 paired t-test option (uncorrected p<0.001). RESULTS: Significant increases in rCBF under ictal conditions were identified in the bilateral anterior cingulate cortex (ACC), the globus pallidus ipsilateral to epileptic foci and the contralateral cerebellar hemisphere. The right ACC included a cluster with a submaximum in the right primary sensorimotor area. DISCUSSION: In patients with SMA seizures, the hyperperfusion areas of ictal SPECT did not localize within the SMA but spread to the adjacent cortex such as the ACC and sensorimotor cortex ipsilateral to epileptic foci. Additionally, the epileptic discharges propagated to the remote areas such as the globus pallidus and cerebellum. We caution that ictal SPECT localization in patients with SMA seizures is not always concordant to epileptic focus but reveals already spread seizure activities.     

Epileptic spasms and partial seizures as a single ictal event

PURPOSE: To investigate the phenomenon of epileptic spasms (ESs) associated with other seizure types in a single ictal event and to study the predictive value of this phenomenon regarding etiology and prognosis. METHODS: We selected retrospectively eight female and five male patients, who had ESs and other seizure types within a single seizure event and for whom a video-EEG recording of the phenomenon was performed in at least one situation. RESULTS: The seizure type associated with ESs was a partial seizure in all patients. We identified three groups with different seizure patterns regarding the temporal association of ES and partial seizures (PSs): (a) PS followed by ES; (b) PS appearing during a cluster of ESs without interrupting the cluster; and (c) complex seizure interaction with a succession of ESs and PSs in a close but variable temporal association. Underlying disorders included cortical dysplasia (three patients), complex cerebral malformations (two patients), and perinatal anoxic-ischemic injuries (two patients); four cases were classified as cryptogenic, and in two children, etiology was unknown, but prenatal origin was suspected. Outcome was poor in nine cases with intractable epilepsy; four cases had a favorable outcome, defined as complete cessation of epileptic seizures. CONCLUSIONS: The phenomenon of associated ESs and PSs as a single ictal event can be related to different etiologies and should not be considered distinctive for cortical malformations or severe brain damage. Different seizure patterns of associated ESs and PSs provide no hint for etiology or prognosis. Outcome is prevalently but not constantly unfavorable in patients with the phenomenon.     

Long-term prospective on-line real-time seizure prediction.

OBJECTIVE: Epilepsy, one of the most common neurological disorders, constitutes a unique opportunity to study the dynamics of spatiotemporal state transitions in real, complex, nonlinear dynamical systems. In this study, we evaluate the performance of a prospective on-line real-time seizure prediction algorithm in two patients from a common database. METHODS: We previously demonstrated that measures of chaos and angular frequency, estimated from electroencephalographic (EEG) signals recorded at critical sites in the cerebral cortex, progressively converge (i.e. become dynamically entrained) as the epileptic brain transits from the asymptomatic interictal state to the ictal state (seizure) (Iasemidis et al., 2001, 2002a, 2003a). This observation suggested the possibility of developing algorithms to predict seizures well ahead of their occurrences. One of the central points in those investigations was the application of optimization theory, specifically quadratic zero-one programming, for the selection of the critical cortical sites. This current study combines that observation with a dynamical entrainment detection method to prospectively predict epileptic seizures. The algorithm was tested in two patients with long-term (107.54h) and multi-seizure EEG data B and C (Lehnertz and Litt, 2004). RESULTS: Analysis from the 2 test patients resulted in the prediction of up to 91.3% of the impending 23 seizures, about 89+/-15min prior to seizure onset, with an average false warning rate of one every 8.27h and an allowable prediction horizon of 3h. CONCLUSIONS: The algorithm provides warning of impending seizures prospectively and in real time, that is, it constitutes an on-line and real-time seizure prediction scheme. SIGNIFICANCE: These results suggest that the proposed seizure prediction algorithm could be used in novel diagnostic and therapeutic applications in epileptic patients.     

Heart rate increase in otherwise subclinical seizures is different in temporal versus extratemporal seizure onset: support for temporal lobe autonomic influence.

Ictal heart rate was investigated in otherwise subclinical epileptic seizures to test the hypothesis as to whether ictal tachycardia is physiological and not a physical or psychological stress response. In addition, we aimed to evaluate the localizing significance of pure ictal tachycardia. We included 21 epilepsy patients, who showed an ictal EEG seizure pattern during 22, otherwise subclinical seizures. All patients underwent ictal video-EEG recordings to evaluate the possibility of resective epilepsy surgery. The changes in heart rate in these patients were investigated in order to determine their relationship to localization and duration of EEG seizure patterns. Ictal tachycardia was observed in 41% of the otherwise subclinical seizures (nine out of 22), and significantly more often in seizures arising from the temporal lobe than from extratemporal regions (62% versus 11%, p < 0.0018). The seizure duration as defined by EEG was significantly positively correlated with an increase of heart rate (p = 0.043). Ictal heart rate can increase as a result of epileptic activation of autonomic cortex, reflecting a temporal lobe autonomic influence. Thus, measurement of heart rate should be included in the evaluation of otherwise subclinical epileptic seizures, because of its localizing value.     

Comparison of heart rate variability parameters during complex partial seizures and psychogenic nonepileptic seizures

Purpose: Psychogenic nonepileptic seizures (PNES) superficially resemble epileptic seizures. Little is known about ictal autonomic nervous system (ANS) activity changes in epilepsy and PNES. This study compares ictal heart rate variability (HRV) parameters as a reflection of ANS tone in epileptic seizures and PNES, and explores differences between interictal and ictal ANS tone in both patient groups. Methods: Ictal HRV parameters were extracted from single‐lead electrocardiography (ECG) data collected during video–electroencephalography (EEG) recordings of 26 patients with medically refractory temporal lobe epilepsy and 24 age‐ and sex‐matched patients with PNES. One seizure per patient in a resting, wake, supine state was analyzed. Interictal ECG data were available for comparison from 14 patients in both groups. HRV parameters in time and frequency domains were analyzed (low frequency [LF], high frequency [HF], standard deviation of all consecutive normal R wave intervals [SDNN], square root of the mean of the sum of the squares of differences between adjacent normal R wave intervals [RMSSD]). CVI (cardiovagal index), CSI (cardiosympathetic index), and ApEn (approximate entropy) were calculated from Lorenz plots. Key Findings: There were significant differences between ictal HRV measures during epileptic and nonepileptic seizures in the time and frequency domains. CSI (p < 0.001) was higher in epileptic seizures. Time interval between two consecutive R waves in the ECG (RR interval) (p = 0.002), LF (p = 0.02), HF (p = 0.003), and RMSSD (p = 0.003) were significantly lower during epileptic seizures. Binary logistic regression yielded a significant model based on the differences in CSI classifying 88% of patients with epilepsy and 73% of patients with PNES correctly. The comparison between resting and ictal states in both seizure disorders revealed significant differences in RR interval (epilepsy p < 0.001, PNES p = 0.01), CSI (epilepsy p < 0.001, PNES p = 0.02), HF (epilepsy p = 0.002, PNES p = 0.03), and RMSSD (epilepsy p = 0.004, PNES p = 0.04). In patients with epilepsy there were also significant differences in ictal versus interictal mean values of ApEn (p = 0.03) and LF (p = 0.04). Although CSI was significantly higher, the other parameters were lower during the seizures. Stepwise binary regression in the 14 patients with epilepsy produced a significant model differentiating resting state from seizures in 100% of cases. The same statistical approach did not yield a significant model in the PNES group. Significance: Our results show greater ANS activation in epileptic seizures than in PNES. The biggest ictal HRV changes associated with epileptic seizures (CSI, HF, and RMSSD) reflect high sympathetic system activation and reduced vagal tone. The reduced ApEn also reflects a high sympathetic tone. The observed ictal alterations of HRV patterns may be a more specific marker of epileptic seizures than heart rate changes alone. These altered HRV patterns could be used to detect seizures and also to differentiate epileptic seizures from PNES. Larger studies are justified with intergroup and intragroup comparisons between ictal and resting states.     

Induction of partial epileptic seizures by flumazenil

PURPOSE: This study addressed the efficacy of flumazenil (FMZ) to induce or activate interictal or ictal epileptic discharges in patients with medically intractable partial epilepsies. METHODS: Flumazenil, 1 mg, was injected intravenously in 67 patients undergoing presurgical monitoring for epilepsy surgery, 49 of whom had been treated with benzodiazepines (BZDs) before flumazenil was given. Continuous video electroencephalogram (EEG) monitoring with surface or intracranial electrodes was used to evaluate interictal EEG activity, ictal discharges, and the occurrence and semiology of clinically manifest epileptic seizures. RESULTS: Interictal epileptiform potentials did not change in frequency or distribution after FMZ. In patients not pretreated with BZDs, epileptic seizures could not be provoked. In eight of the 49 patients pretreated with BZDs, epileptic seizures occurred within 30 min of FMZ application. Seizure semiology and regional EEG onset were identical to seizures recorded without FMZ. Patients operated on according to seizure-onset localization with FMZ had a >75% reduction in seizure frequency or became seizure free. CONCLUSIONS: Seizure induction by FMZ seems to be a valid method for evaluating seizure semiology and localization of the seizure-onset zone during presurgical monitoring of patients with medically intractable localization-related epilepsies.     

Ictal SPECT in supplementary motor area seizures

Abstract

Objectives: We used ictal single photon emission computed tomography (SPECT) to clarify the propagation pathways of epileptic discharges in patients with supplementary motor area (SMA) seizure.

Methods: In four patients (four males, age range, 18–27 years) with SMA seizures, SPECT studies by radioisotope 99mTc-ECD were performed as a preoperative evaluation. Two of the patients remained seizure-free after complete resection of the focal cortical dysplasia on magnetic resonance (MR) images including epileptic foci. In the other two patients, MR images were normal, but subdural electrode monitoring allowed for verifying the ictal onset in the left SMA. After partial resection of the SMA including epileptic foci, these patients experienced a significant (>90%) reduction of seizure frequency. Regional cerebral blood flow (rCBF) measurements obtained under ictal and interictal conditions were compared on a voxel-by-voxel basis by means of the SPM99 paired t-test option (uncorrected p<0.001).

Results: Significant increases in rCBF under ictal conditions were identified in the bilateral anterior cingulate cortex (ACC), the globus pallidus ipsilateral to epileptic foci and the contralateral cerebellar hemisphere. The right ACC included a cluster with a submaximum in the right primary sensorimotor area.

Discussion: In patients with SMA seizures, the hyperperfusion areas of ictal SPECT did not localize within the SMA but spread to the adjacent cortex such as the ACC and sensorimotor cortex ipsilateral to epileptic foci. Additionally, the epileptic discharges propagated to the remote areas such as the globus pallidus and cerebellum. We caution that ictal SPECT localization in patients with SMA seizures is not always concordant to epileptic focus but reveals already spread seizure activities.     

Depth recorded limbic seizures and psychopathology

Chronically performed stereotaxic depth recordings in medically intractable epileptics offer a unique chance to study the correlation of epileptic discharges with changes of higher mental functions as well as behavioral and emotional alterations. From a quantitative study using 213 complex partial seizures from 29 selected patients with partial drug resistant epilepsy and from the observation of other patients with well defined epileptic perturbations of the limbic system and related sensory brain areas a good correlation between ictal signs and chronotopographical seizure patterns was obtained. The special role of mesiobasal limbic structures, i.e., amygdala and hippocampus, and its connections to hypothalamic and frontobasal-cingulate areas is highlighted by tracing the seizures. It is concluded that besides the short-lived ictal abberations of mental state and emotional sphere ("psychical seizures") also some of the more prolonged behavior and personality changes seen frequently in patients with bitemporal basal spike foci might be attributed to narrowly confined limbic seizure discharges or to a "limbic dyscontrol syndrome" based on the altered activity of limbic structures due to the spike foci.     

Topographic movie of intracranial ictal high-frequency oscillations with seizure semiology: epileptic network in Jacksonian seizures

Purpose: We developed a technique to produce images of dynamic changes in ictal high‐frequency oscillations (HFOs) >40 Hz recorded on subdural electroencephalography (EEG) that are time‐locked to the ictal EEG and ictal semiology video. We applied this technique to Jacksonian seizures to demonstrate ictal HFO propagation along the homunculus in the primary sensory‐motor cortex to visualize the underlying epileptic network. Methods: We analyzed intracranial ictal EEGs from two patients with intractable Jacksonian seizures who underwent epilepsy surgery. We calculated the degrees of increase in amplitude within 40–80, 80–200, and 200–300 Hz frequency bands compared to the interictal period and converted them into topographic movies projected onto the brain surface picture. We combined these data with the ictal EEGs and video of the patient demonstrating ictal semiology. Key Findings: The ictal HFOs began in the sensory cortex and appeared concomitantly with the sensory aura. They then propagated to the motor cortex at the same time that focal motor symptoms evolved. As the seizure progressed, the ictal HFOs spread or reverberated in the rolandic region. However, even when the seizure became secondarily generalized, the ictal HFOs were confined to the rolandic region. In both cases, there was increased amplitude of higher frequency bands during seizure initiation compared to seizure progression. Significance: This combined movie showed the ictal HFO propagation corresponding to the ictal semiology in Jacksonian seizures and revealed the epileptic network involved in seizure initiation and progression. This method may advance understanding of neural network activities relating to clinical seizure generation and propagation.     

Clinical and ictal characteristics of infantile seizures: EEG correlation via long-term video EEG monitoring

Purpose

The semiology of infantile seizures often shows different characteristics from that of adults. We performed this study to describe clinical and ictal characteristics of infantile seizures at less than two years of age.

Methods

A retrospective study was done for infants with epilepsy (ages: 1–24 months) who underwent long-term video electroencephalography (EEG) monitoring at Samsung medical center between November 1994 and February 2012. We analyzed the clinical and ictal characteristics of the 56 cases from 51 patients.

Results

In 69% of the patients, the seizure onset was before six months of age and the etiology was symptomatic in one third of the patients. Twelve seizure types were identified; spasms (24%), unilateral motor seizures (18%), and generalized tonic seizures (15%) were the three frequent types of seizure.All partial seizures were well correlated with the partial-onset ictal EEG, however 19.4% (7/36) of clinically generalized seizures revealed partial-onset ictal EEG. About one-thirds (4/11) of generalized tonic seizures had its ictal onset on unilateral or bilateral frontal areas and two out of seven generalized myoclonic seizures showed unilateral frontal rhythmic activities. Hypomotor seizures mainly arose from the temporal areas and hypermotor seizures from the frontal regions.

Conclusions

Even though most of the seizure semiology of infants is well correlated with ictal EEG, some of the generalized tonic seizures or myoclonic seizures revealed partial-onset ictal EEG suggesting localized epileptic focus. Accurate definition of seizures via video EEG monitoring is necessary for proper management of seizures in infancy, especially in some clinically generalized seizures.     

"Convulsive" nonepileptic seizures have a characteristic pattern of rhythmic artifact distinguishing them from convulsive epileptic seizures

PURPOSE: Approximately 30% of patients admitted for video-EEG monitoring have psychogenic nonepileptic seizures (PNES). Differentiation of "convulsive" PNES from convulsive seizures can be difficult. The EEG often displays rhythmic movement artifact that may resemble seizure activity and confound the interpretation. We sought to determine whether time-frequency mapping of the rhythmic EEG artifact during "convulsive" PNES reveals a pattern that differs from that of epileptic seizures. METHODS: EEGs from 15 consecutive patients with "convulsive" PNESs were studied with time-frequency mapping by using NEUROSCAN and compared with 15 patients with convulsive epileptic seizures. Fast Fourier transforms (FFTs) were performed to determine the dominant frequency for 1- to 2-s windows every 2 s through the seizures. RESULTS: The dominant frequency remained stable within a narrow range for the duration of the PNES, whereas in the epileptic seizures, it evolved through a wide range. The coefficient of variation of the frequency during the seizures was considerably less for patients without epilepsy (median, 15.0%; range, 7.2-23.7% vs. median, 58.0%; range, 34.8-92.1%; p < 0.001). The median frequency did not differ significantly between groups (4.2 vs. 4.6 Hz; p = 0.290). CONCLUSIONS: "Convulsive" PNES display a characteristic pattern on time-frequency mapping of the EEG artifact, with a stable, nonevolving frequency that is different from the evolving pattern seen during an epileptic seizure.     

Brain activation patterns of versive, hypermotor, and bilateral asymmetric tonic seizures

Purpose: Patients who have seizure onset from different brain regions can produce seizures that appear clinically indistinguishable from one another. These clinically stereotypic manifestations reflect epileptic activation of specific networks. Several studies have shown that ictal perfusion single photon emission computed tomography (SPECT) can reveal propagated ictal activity. We hypothesize that the pattern of hyperperfusion may reflect neuronal networks that generated specific ictal symptomatology. Methods: All patients were identified who were injected with ^99mTc‐hexamethyl‐propylene‐amine‐oxime (HMPAO) during versive seizures (n = 5), bilateral asymmetric tonic seizures (BATS; n = 5), and hypermotor seizures (n = 7) in the presurgical epilepsy evaluation between 2001 and 2005. The SPECT ictal–interictal difference image pairs of each subgroup were compared with image pairs of 14 controls using statistical parametric mapping (SPM 2) to identify regions of significant hyperperfusion. Hyperperfused regions with corrected cluster‐level significance p < 0.05 were considered significant. Results: We have identified a distinct ictal perfusion pattern in each subgroup. In versive seizure subgroup, prominent hyperperfusion was present in the frontal eye field opposite to the direction of head version. In addition, there was associated caudate and crossed cerebellar hyperperfusion. The BATS subgroup showed pronounced hyperperfusion supplementary sensorimotor area ipsilateral to the epileptogenic region, bilateral basal ganglia, and contralateral cerebellar hemisphere. The hypermotor seizure subgroup demonstrated two clusters of significant hyperperfusion: one involving bilateral frontomesial regions, cingulate gyri, and caudate nuclei, and another involving ipsilateral anteromesial temporal structures, frontoorbital region, insula, and basal ganglia. Discussion: We have identified distinct hyperperfusion patterns for specific ictal symptomatology. Our findings provide further insight into understanding the anatomic basis of seizure semiology.     

Detecting epileptic seizures in long-term human EEG: a new approach to automatic online and real-time detection and classification of polymorphic seizure patterns.

Epileptic seizures can cause a variety of temporary changes in perception and behavior. In the human EEG they are reflected by multiple ictal patterns, where epileptic seizures typically become apparent as characteristic, usually rhythmic signals, often coinciding with or even preceding the earliest observable changes in behavior. Their detection at the earliest observable onset of ictal patterns in the EEG can, thus, be used to start more-detailed diagnostic procedures during seizures and to differentiate epileptic seizures from other conditions with seizure-like symptoms. Recently, warning and intervention systems triggered by the detection of ictal EEG patterns have attracted increasing interest. Since the workload involved in the detection of seizures by human experts is quite formidable, several attempts have been made to develop automatic seizure detection systems. So far, however, none of these found widespread application. Here, we present a novel procedure for generic, online, and real-time automatic detection of multimorphologic ictal-patterns in the human long-term EEG and its validation in continuous, routine clinical EEG recordings from 57 patients with a duration of approximately 43 hours and additional 1,360 hours of seizure-free EEG data for the estimation of the false alarm rates. We analyzed 91 seizures (37 focal, 54 secondarily generalized) representing the six most common ictal morphologies (alpha, beta, theta, and delta- rhythmic activity, amplitude depression, and polyspikes). We found that taking the seizure morphology into account plays a crucial role in increasing the detection performance of the system. Moreover, besides enabling a reliable (mean false alarm rate<0.5/h, for specific ictal morphologies<0.25/h), early and accurate detection (average correct detection rate>96%) within the first few seconds of ictal patterns in the EEG, this procedure facilitates the automatic categorization of the prevalent seizure morphologies without the necessity to adapt the proposed system to specific patients.     

Utility of the Scalp-Recorded Ictal EEG in Childhood Epilepsy

PURPOSE: To evaluate the usefulness of the scalp-recorded ictal EEGs in diagnosing childhood epilepsy. METHODS: We analyzed the ictal EEGs of 259 seizures in 183 patients who visited the department of child neurology, Okayama University Medical School, during the past 6 years. RESULTS: We divided all seizures into the following four categories, according to the diagnostic usefulness of ictal EEGs in determining the seizure type: 1. (a) Ictal EEGs confirmed the diagnosis of the seizure type based on seizure symptoms (101 seizures); (b) Ictal EEGs aided in the classification of the seizure type based on the seizure symptoms (101 seizures); (c) Ictal EEGs corrected errors in the classification (37 seizures); and (d) Ictal EEGs revealed previously unreported/undocumented seizure type (20 seizures). 2. Of the 37 misdiagnosed seizures (group C), 11 were nonepileptic seizures misdiagnosed as epileptic seizures, eight were complex partial seizures (CPS) misdiagnosed as the other seizure types, and 10 were other seizure types misdiagnosed as CPSs. 3. Of the 20 previously unreported/undocumented seizures (group D), nine were myoclonic seizures, five were absence seizures, five were CPS, and one was tonic spasms. 4. Seventy-two patients had CPS. Among them, 11 patients showed no epileptic spikes in their interictal EEG recordings. Therefore, ictal recordings confirmed the diagnosis of epilepsy. CONCLUSIONS: Ictal EEG recording is a very useful diagnostic tool not only for determining seizure types, but also for uncovering the existence of the unsuspected seizure types. It supplies the physician with useful information for the classification and the treatment of epilepsy. In particular, ictal EEGs are useful in diagnosing patients with CPS.     

Spécificités des crises d’épilepsie chez le sujet âgé : proposition d’un score électro-radioclinique d’orientation

Diagnosis of epileptic seizure may be difficult in older patients because seizure manifestations are often unusual: confusion, paresis… and because there are multiple differential diagnoses (syncope, transient ischemic attack, transient global amnesia…). To promote and facilitate the diagnosis of seizures in the elderly, neurologists and gerontologists must work together and focus their strategy on two points: firstly, the knowledge of the specific presentation of seizures in elderly patients, and secondly, the adoption of a reasoning based on seizures and not epileptic syndromes. A multidisciplinary group worked on epilepsy of the elderly to elaborate an electro-clinical score which aims to help establish the diagnosis of epilepsy in elderly patients in different clinical settings. This electro-clinical score is based on a systematic review of scientific literature and the recommendations are explicitly linked to supporting evidence. Further, clinical validation of the electro-clinical score is required.     

Involvement of medial pulvinar thalamic nucleus in human temporal lobe seizures

PURPOSE: Several animal studies suggest that the thalamus might be involved in the maintenance and propagation of epileptic seizures. However, electrophysiologic evidence for this implication in human partial epileptic seizures is still lacking. Considering the rich and reciprocal connectivity of the medial pulvinar (PuM) with the temporal lobe, we evaluated a potential participation of this thalamic nucleus in temporal lobe epilepsy (TLE). METHODS: The electrophysiologic activity of PuM was recorded during stereoelectroencephalographic exploration of spontaneous temporal lobe seizures in 14 patients referred for presurgical assessment of refractory TLE. RESULTS: We recorded PuM ictal activity in 80% of the 74 seizures that we analyzed. This activity was characterized by rhythmic slow-waves or rhythmic spikes (RSW-RS) or both or by low-voltage fast activity (LVFA) in 64% and 36% of seizures, respectively. RSW-RS occurred mostly in seizures arising from mesiotemporal structures, whereas LVFA was more frequently observed in seizures of neocortical origin. In the 15 seizures without PuM ictal activity, spreading of the seizure outside the onset zone never occurred, whereas it did in 78% of seizures with PuM ictal involvement. Discharge propagation was systematic when PuM involvement corresponded to LVFA, whatever the seizure onset zone was, whereas it represented only 66% of the seizures when PuM exhibited RSW-RS. CONCLUSIONS: This study shows that ictal changes in PuM activity are frequently observed during temporal lobe seizures and suggests that this thalamic nucleus might participate in their propagation.     

Similar semiology of epileptic and psychogenic nonepileptic seizures recorded during stereo-EEG

We report two adolescents with refractory seizure disorders in whom both epileptic and psychogenic nonepileptic seizures (PNES) were recorded with intracerebral EEG. The ictal phenomenology of epileptic seizures (ES) and PNES, consisting of hypermotor attacks in the first patient and left-sided painful episodes in the second patient, proved remarkably similar in both cases, highlighting the difficulties which can arise with the distinction of epileptic seizures and PNES based on ictal phenomenology alone.