Usefulness of multidetector-row computerized tomographic angiography for the surgical planning in stereoelectroencephalography.

PURPOSE: Surgical planning of depth electrode implantation in stereo-electro-encephalography (SEEG) routinely uses magnetic resonance imaging (MRI) alone. Accurate visualization of arteries and veins in the vicinity of the electrode is essential to plan a safe trajectory to presumably reduce the risk of intracranial bleeding. The goal of this study was to compare multidetector row computerized tomographic angiography (MDCTA) with MRI for the visualization of vessels along each planned trajectory in patients who undergo SEEG. MATERIALS AND METHODS: Ten consecutive patients who were scheduled to undergo SEEG procedure were included. T1-weighted gadolinium-chelate enhanced MR sequence, stereotactic MDCT and MDCTA were performed after fixation of Leksell's frame. For each of the 106 planned stereotactic trajectories, the number of vessels in a 4.0mm diameter circle around the trajectory from the dura mater to the target that were visible on MDCTA were compared to that of visible vessels in the same areas on MRI. RESULTS: Ten vessels (10/106; 9.4%) were seen on MRI and 66 (66/106; 62.3%) on MDCTA (P<0.0001). All vessels visible on MRI were visible on MDCTA. The difference in number of visible vessels between the two techniques remained significant for the different lobes (i.e., frontal lobe, temporal lobe and parieto-occipital lobe). CONCLUSION: MDCTA enabled visualization of more vessels than MRI based SEEG. MDCTA may help neurosurgeons better define the trajectory of the electrode and reduce the risk of intracranial bleeding.

Continuous EEG monitoring in adults in the intensive care unit (ICU).

Continuous EEG monitoring in the ICU is different from planned EEG due to the rather urgent nature of the indications, explaining the fact that recording is started in certain cases by the clinical team in charge of the patient's care. Close collaboration between neurophysiology teams and intensive care teams is essential. Continuous EEG monitoring can be facilitated by quantified analysis systems. This kind of analysis is based on certain signal characteristics, such as amplitude or frequency content, but raw EEG data should always be interpreted if possible, since artefacts can sometimes impair quantified EEG analysis. It is preferable to work within a tele-EEG network, so that the neurophysiologist has the possibility to give an interpretation on call. Continuous EEG monitoring is thus useful in the diagnosis of non-convulsive epileptic seizures or purely electrical discharges and in the monitoring of status epilepticus when consciousness disorders persist after initial treatment. A number of other indications are currently under evaluation.

[French guidelines on electroencephalogram]. / Recommandations françaises sur l'électroencéphalogramme.

Electroencephalography allows the functional analysis of electrical brain cortical activity and is the gold standard for analyzing electrophysiological processes involved in epilepsy but also in several other dysfunctions of the central nervous system. Morphological imaging yields complementary data, yet it cannot replace the essential functional analysis tool that is EEG. Furthermore, EEG has the great advantage of being non-invasive, easy to perform and allows control tests when follow-up is necessary, even at the patient's bedside. Faced with the advances in knowledge, techniques and indications, the Société de Neurophysiologie Clinique de Langue Française (SNCLF) and the Ligue Française Contre l'Épilepsie (LFCE) found it necessary to provide an update on EEG recommendations. This article will review the methodology applied to this work, refine the various topics detailed in the following chapters. It will go over the summary of recommendations for each of these chapters and underline proposals for writing an EEG report. Some questions could not be answered by the review of the literature; in those cases, an expert advice was given by the working and reading groups in addition to the guidelines.

Large-field repetitive transcranial magnetic stimulation with circular coil in the treatment of functional neurological symptoms.

OBJECTIVE: Patients with functional neurological symptoms (FNS) are frequently encountered by neurologists and are difficult to treat. Symptoms are multiple and may appear concurrently or successively in the same patient. To date, few studies have been published on focal repetitive transcranial magnetic stimulation (rTMS) in FNS. This type of stimulation induces a focal current, vertically in the cortex. Results are contradictory, probably because it is difficult to identify a limited cortical area that triggers these symptoms. We assessed the efficacy of another type of rTMS: large-field stimulation by means of a circular coil covering a surface area approximately 20 times greater and inducing a circular current tangentially to the cortex. PUBLISHED STUDIES: We analysed two studies on the efficacy of large-field rTMS in functional paralysis and in functional movement disorders. The efficacy of large-field rTMS was very marked in these two studies. PERSONAL NON-PUBLISHED STUDIES: We reported several open series, including patients with functional sensory loss, functional visual loss, and non-epileptic seizures. METHOD: For all patients, one or several sessions of 60 stimuli with circular coil were carried out with a protocol depending on the symptoms. RESULTS: The efficacy of large-field rTMS was dramatic in all patient series. Additionally, we discuss the possible involved mechanism: placebo effect, cognitive behavioural effect or neuromodulatory effect. CONCLUSION: According to the data from these different studies, large-field rTMS could be a new therapy for patients with FNS. However, controlled studies are mandatory.

[Management of convulsive status epilepticus in infants and children]. / Prise en charge d'un état de mal épileptique de l'enfant (nouveau-né exclu).

Convulsive status epilepticus in childhood is a life threatening condition with serious risk of neurological sequelae which constitutes a medical emergency. Clinical and experimental data suggest that prolonged seizures can have immediate and long-term adverse consequences on the immature and developing brain. So the child who presents with a continuous generalized convulsive seizure lasting greater than five minutes should be promptly treated. The outcome is mainly determined by the underlying etiology, age and duration of status epilepticus. In children the mortality from status epilepticus ranges from 3 to 5% and the morbidity is two-fold higher. Mortality and morbidity are highest with status epilepticus associated with central nervous system infections, which is the most important cause of status epilepticus. There are few evidence-based data to guide management decisions for the child with status epilepticus. Immediate goals are stabilization of airways, breathing and circulation and termination of seizures. Benzodiazepines remain the first-line drugs recommended for prompt termination of seizures. As intravenous lorazepam is not available in France, we suggest clonazepam as the best choice for initial therapy. Rectal diazepam or buccal midazolam remain important options. Intravenous phenytoin/fosphenytoin and phenobarbital are the second-line drugs. Phenytoin is being increasingly substituted by fosphenytoin, but pediatric data are scarce and fosphenytoin is not authorized for use in France below five years old. In children, phenytoin is often preferred to phenobarbital, even though no comparative studies have demonstrated a better efficacy. To manage status epilepticus refractory to a benzodiazepine and administration of phenytoin and/or phenobarbital, many pediatricians today prefer high-dose midazolam infusion rather than thiopental to minimize serious side effects from barbiturate anesthesia. There is no benefit/risk ratio to support the use of propofol for children with refractory status epilepticus.

Clinical features of primary headache in children: a multicentre hospital-based study in France.

The aim of this study was to evaluate the concordance between clinical diagnosis and the International Classification of Headache Disorders, 2nd edn (ICHD-II) in children and adolescents with primary headaches. This 6-month prospective multicentre study of 486 patients (mean 9.8 +/- 3.1 years; 52.6% girls) assessed the headache features through a structured questionnaire. In 398 patients with a single type of headache, headaches were bilateral (78.1%), frontal (62.4%), pulsatile (56.1%), with associated symptoms in 84.4%. The most frequently assigned diagnoses were migraine without aura (50.8%), probable migraine (14.1%), migraine with aura (11.1%) and frequent episodic tension-type headache (7.5%). For most of the diagnostic categories, the consistency of the investigator's diagnosis with the ICHD-II criteria was good (kappa > 0.6 and < or = 0.8) or excellent (kappa > 0.8). We conclude that migraine was predominant with regard to headache diagnoses repartition and that the ICHD-II seems usable in practice for evaluation of primary headache in French children and adolescents.

Severe attacks of familial hemiplegic migraine, childhood epilepsy and ATP1A2 mutation.

We studied four members of a family suffering from typical attacks of familial hemiplegic migraine (FHM) caused by a new mutation, R548C, of ATP1A2 gene in exon 12. One individual had also childhood absence epilepsy and generalized tonic-clonic seizures (GTCS). GTCS were followed by a severe attack of hemiplegic migraine at four times. Sodium valproate enabled control of both the epileptic seizures and the most severe FHM attacks. This association of FHM and epileptic seizures and their control with the same treatment suggest similar pathophysiological mechanisms.

Evaluation of brivaracetam, a novel SV2A ligand, in the photosensitivity model.

OBJECTIVE: To assess the activity of brivaracetam, a novel SV2A ligand, in the photosensitivity model as a proof-of-principle of efficacy in patients with epilepsy. METHODS: A subject-blind placebo-controlled study in patients with photosensitive epilepsy was performed to investigate the effect of single-dose brivaracetam (10, 20, 40, or 80 mg) on photosensitive responses. Each patient was exposed to intermittent photic stimulation that evoked a generalized photoparoxysmal EEG response. Individual standard photosensitivity ranges (SPRs) were recorded post-placebo (day -1) and post-brivaracetam until return to baseline (day 1 to 3). Plasma concentrations of brivaracetam and any concomitant antiepileptic drugs were determined. RESULTS: Of the 18 evaluable patients, none achieved SPR abolishment post-placebo, whereas 14 (78%) achieved complete abolishment post-brivaracetam. Decrease in SPR was seen in 8 patients (44%) post-placebo compared to 17 (94%) post-brivaracetam. Duration of response was twice as long post-brivaracetam 80 mg (59.5 hours) compared with lower doses, although the overall effect was not dose-dependent. Time to maximal photosensitive response was dose-related with the shortest time interval observed at the highest dose (0.5 hours post-brivaracetam 80 mg). The area under the effect curve (SPR change from pre-dose vs time) appeared linearly correlated with the area under the plasma concentration curve. Brivaracetam was well tolerated. The most common adverse events were dizziness and somnolence. CONCLUSIONS: Our findings show that brivaracetam clearly suppresses generalized photoparoxysmal EEG response. As such, investigations of the antiepileptic properties and tolerability of brivaracetam are warranted in further clinical studies of patients with epilepsy.

Migraine aura lasting 1-24 h in children: a sequence of EEG slow-wave abnormalities vs. vascular events.

The aim of this study was to describe the abnormalities associated with migraine aura lasting 1-24 h in children as shown by EEG, trancranial Doppler (TCD) and single photon emission computed tomography (SPECT). In this retrospective study, 11 patients each underwent EEG, TCD and brain SPECT on the day of admission and the day thereafter. On the day of admission, the migrainous hemisphere of all patients showed that the mean velocities were decreased in the middle cerebral artery by TCD, slow-wave abnormalities were recorded after several hours of aura by EEG and the SPECT showed hypoperfusion. On the day after, in the same hemisphere, slow waves were recorded only in the occipital area by EEG, and SPECT showed slight hyperperfusion. In these patients, there was a clear sequence of EEG, TCD and SPECT abnormalities.

Vagal nerve stimulation in tuberous sclerosis complex patients.

This is an open-label, retrospective, multicenter study to determine the outcome of intermittent stimulation of the left vagal nerve in children with tuberous sclerosis complex and medically refractory epilepsy. The records of all children treated with vagal nerve stimulation were reviewed in five pediatric epilepsy centers to locate those with tuberous sclerosis complex who had been treated with vagal nerve stimulation for at least 6 months. These patients were compared with (1) a series of patients obtained from the literature, (2) 10 similar control patients with epilepsy obtained from a registry of patients receiving vagal nerve stimulation, and (3) four published series of tuberous sclerosis complex patients whose epilepsy was surgically managed. Ten tuberous sclerosis complex patients with medically refractory epilepsy treated with vagal nerve stimulation were found. Nine experienced at least a 50% reduction in seizure frequency, and half had a 90% or greater reduction in seizure frequency. No adverse events were encountered. Comparison with published and registry patients revealed improved seizure control in the tuberous sclerosis complex patients. Comparison with the group undergoing seizure surgery demonstrated improved outcomes after surgery. Vagal nerve stimulation appears to be an effective and well-tolerated adjunctive therapy in patients with tuberous sclerosis complex and seizures refractory to medical therapy. Resective surgery has a better prospect for improved seizure control.

[Photosensitive epilepsy and television epilepsy]. / Epilepsies photosensibles et épilepsie de la télévision.

Photosensitivity is defined by the appearance of occipital or more diffuse electroencephalographic spikes and waves induced by intermittent light stimulation (ILS), particular patterns, TV-watching, and video games. Photosensitivity is a genetic characteristic. Only the diffuse spikes and waves induced by ILS are correlated with epilepsy. Pure photogenic epilepsy is characterized by seizures which are only visually induced, usually by watching TV. Video games sometimes add a trigger effect due to slowly moving patterns or intense brightness. Several epileptic syndromes are associated with a photosensitivity with or without visually-induced seizures, mainly generalized idiopathic epilepsy.

[Localized neonatal convulsions and cerebral arterial infarction]. / Convulsions néonatales focalisées et infarctus artériel cérébral.

BACKGROUND: Stroke is a rare cause of neonatal seizures. CASE REPORTS: During a 5-year period, eight full-term infants were admitted to hospital for seizures due to a stroke. Seizures began shortly after birth and were always one-sided. Early CT scans showed cerebral infarctions. Motor disabilities such as hemiparesis were found in three out of seven cases; language difficulties were observed in the same proportion; however all the children had not reached school age. CONCLUSION: Neonatal localized seizures may be symptomatic of a stroke and therefore justify a computerized tomography (CT) scan. Motor and cognitive sequelae require early management.

[Generalized or focal photosensitive epilepsies]. / Les épilepsies photosensibles généralisées ou focales.

Photosensitivity is defined by a pattern of occipital or more diffuse spikes and waves. Several techniques are needed for exploration: intermittent light stimulation (ILS), patterns, TV-screen, video games. Photosensitivity is a genetic characteristic. Only diffuse spikes and waves induced by ILS are correlated with epilepsy. Pure photogenic epilepsy is characterized by seizures induced by visual stimuli alone, usually by TV-screen. Video games may also have a triggering effect due to the slow-moving patterns or intense brightness. Several epileptic syndromes are associated with photosensitivity with or without visually-induced seizures. These syndromes are most often generalized and idiopathic.

Epilepsies and video games: results of a multicentric study.

OBJECTIVES: The purpose of this study was to research whether or not video games may induce paroxysmal discharges (PD) in different groups of patients. METHODS: One hundred and fifteen subjects from 5 different French laboratories were studied: 33 had seizures exclusively under visual stimuli, 42 had both photogenic seizures and spontaneous seizures occuring independently, and 40 had non-photogenic seizures. The same protocol which included one TV sequence, 3 sequences of video games selected on particular criteria (pattern, luminosity and nature of the scene), were presented at different distances from the TV screen at 50 and 100 Hz. RESULTS: Among the factors provoking paroxysmal discharges (PD) some seem crucial: the frequency of the TV screen (the 100 Hz screen was significantly safer than 50 Hz), the distance from the screen (1 m safer than 50 cm), and, particularly for the 50 Hz screen, the specific pattern of the images and the act of playing. CONCLUSIONS: Video games are ineffective for subjects known as having a non-photosensitive epilepsy, but may induce PD on subjects known as photosensitive even when intermittent light stimulation (ILS) is not effective. These results based on a different approach than in other publications confirm data which were suggested by the literature, and suggest that 100 Hz TV screens should be recommended to patients with TV-induced attacks.

Prognostic value of neonatal electroencephalography in premature newborns less than 33 weeks of gestational age.

In a prospective study of 417 premature neonates born before 33 weeks' gestational age, neonatal tracings were reviewed to evaluate the use of EEG in prognosis of neurological injuries. The population was divided into two groups: Group 1, infants who died before the age of 1, and Group 2, survivors in which two categories of motor development were considered. Category A, were abnormal, and Category B, were always normal. Positive rolandic sharp waves (PRSW), which reflect white matter injury, occurred equally in both groups, indicating a similar incidence of white matter damage in Groups 1 and 2. In Group 2, there was a significant correlation of PRSW with developmental motor sequelae (Category A). A frequency of PRSW above 2/min (suggesting more severe periventricular white matter injury) and seizures were significantly more prevalent in Group 1 than in Group 2 and in Category A of Group 2 than in Category B. Background abnormalities occurred equally in both subgroups of extremely premature infants (< or = 28 weeks' gestation) they were significantly more numerous in the subgroup of very premature infants (between 28 and 33 weeks' gestation) who died, than in the subgroup of very premature infants who survived. This study shows the potential utility of using neonatal EEG in association with transfontanellar ultrasonography in anticipating the neurological development of very (> 28 weeks' gestation) and extremely (< or = 28 weeks' gestation) premature newborns.

[EEG recordings during episodes of palinacousis and palinopsia]. / Enregistrements EEG contemporains d'épisodes de palinacousie et de palinopsie.

Palinopsia (visual perseveration) and palinacousis (auditory perseveration) are reported in a 51-year-old woman with a left temporo parietal astrocytoma. EEG showed a left temporal delta-focus with sharp waves. EEG was not modified during neither palinacousis nor palinopsia. The relationship between the two hallucinatory phenomena and epilepsy is discussed.

[Dyschromatopsia: manifestation or epiphenomenon in the course of diabetic neuropathy]. / La dyschromatopsie: manifestation ou épiphénomène au cours de la neuropathie diabétique?

We performed a study in 92 diabetic patients (76 Type 1 and 16 Type 2) without retinopathy to determine the relation between diabetic dyschromatopsia and neuropathy, which has been evoked in previous studies. Color vision was explored with Lanthony's desaturated D 15 panel. Peripheral nervous function was explored with an electrophysiological score which has been beforehand validated. Moreover evoked visual potentials were performed in 38 diabetic subjects in order to determine whether dyschromatopsia was related to an impairment of central optic pathways. Fifty-one among the 92 diabetic subjects had a blue-yellow dyschromatopsia. Among the recorded parameters, only peripheral nervous impairment was significantly more frequent in the group with dyschromatopsia than in the group without. Ten among 38 diabetics had impairment of the evoked visual potentials. Frequency of alteration of evoked visual potentials was not different between the group with and the group without dyschromatopsia. Our results confirm the relationship between dyschromatopsia and the alteration of the nervous function in diabetic subjects. In return, lack of significant modification of evoked visual potentials among diabetic patients with dyschromatopsia and the blue-yellow axis of dyschromatopsia are in opposition with a direct neurological origin of dyschromatopsia. We therefore evoke a common process in the beginning of the diabetic dyschromatopsia and of peripheral neuropathy.

[Long term evaluation of sensation sequelae of bipedicled digital advancement island flaps. Comparison of clinical and electrophysiological results. Apropos of 13 cases]. / Evaluation à long terme des séquelles sensitives des lambeaux en îlot bipédiculés d'avancement digitaux. Confrontation des résultats cliniques et électriques. A propos de 13 cas.

Thirteen homodigital bipedicle island flaps for digital pulp amputation were reviewed to allow a better evaluation of sensory sequelae. A clinical and electrophysiological study of the sensory score of the pulp were compared to the contralateral normal digit and expressed in relative values. Sensory sequelae, even minor, are constant. The summated scores of dynamic and static 2 point discrimination test, appeared correlated to the electrophysiological amplitude modulations. This result seems particularly interesting as it adds another test for the objective evaluation of sensitivity.

Positive rolandic sharp waves in the EEG of the premature newborn: a five year prospective study.

In a prospective study of 301 premature newborn infants, neonatal tracings were done to evaluate the use of the electroencephalogram (EEG) and positive rolandic sharp waves (PRSW) in the diagnosis and prognosis of periventricular leucomalacia. Each infant had ultrasonographic studies and standardised neurological examinations at 1 year of age or later. Two hundred and eighty infants were followed up at 1 year. This study demonstrated that the absence of PRSW was correlated with a favourable motor development (98.2%) and confirmed the great value of PRSW in the diagnosis and the prognosis of periventricular leucomalacia. PRSW were sensitive (98%) and specific (84%) markers of developmental motor disability and were a sensitive (96%) marker of severe spastic diplegia. A frequency above 2/minute was a specific (92%) sign of severe spastic diplegia. Social and language developmental abnormalities were not correlated with the neonatal EEG.