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Introduction Stent-assisted coiling has widened indications and improved stability of endovascular treatment of intracranial aneurysms. However, stent-assisted coiling is usually not used to treat acutely ruptured intracranial aneurysms to avoid antiplatelet therapy. The objective of this study is to evaluate a strategy of staged endovascular treatment of ruptured intracranial aneurysms including coiling at the acute phase with complementary stenting with or without coiling at the subacute phase. Material and methods Between 2012 and 2017, we retrospectively identified, in our prospectively maintained database, all patients treated for a ruptured intracranial aneurysm based on this staged stenting strategy. Clinical charts and imaging follow-up were analyzed to assess the procedural safety and feasibility as well as clinical and anatomical outcome. Results We identified 23 patients with 23 intracranial aneurysms including 15 (65.2%) women with a mean age of 50 years (range 24–69 years). No rebleeding occurred during the mean delay of 24.3 days between initial coiling and stenting. All procedures were successful and additional coiling was performed in 5/23 procedures (21.7%). Clinical status was unchanged in all patients. At follow-up, the modified Rankin scale was graded 0 in 19/23 (82.6%), 1 in 2/23 (8.7%), and 2 in 2/23 (8.7%) patients, respectively. The rate of complete occlusion rose from 30.4% before the stenting procedure to 52.2% immediately after and 72.7% at follow-up. Conclusion This strategy of early staged stenting in selected patients is safe and improves immediate intracranial aneurysm occlusion and long-term stability in this population at high risk of intracranial aneurysm recurrence with coiling alone.

Previous studies investigating cerebral metabolic changes associated with continuous spike-waves during sleep (CSWS) compared the metabolism of children with CSWS with that of healthy adults, precluding any assessment in brain areas showing physiologic age-related metabolic changes. Here, we investigated the metabolic and connectivity changes characterizing the acute phase of CSWS activity by comparing awake brain metabolism of children with CSWS with that of pediatric pseudo-controls. Positron emission tomography using [18F]-fluorodeoxyglucose (FDG-PET) was performed in 17 awake children with cryptogenic CSWS (5 girls, age: 5-11 years). Voxel-based analyses identified significant metabolic changes in CSWS patients compared with 18 pediatric pseudo-controls (12 girls, age: 6-11 years, non-CSWS focal cryptogenic epilepsy with normal FDG-PET). CSWS-induced changes in the contribution of brain areas displaying metabolic changes to the level of metabolic activity in other brain areas were investigated using pathophysiological interaction. Hypermetabolism in perisylvian regions bilaterally and hypometabolism in lateral and mesial prefrontal cortex, precuneus, posterior cingulate cortex and parahippocampal gyri characterized the acute phase of CSWS (p0.05 FWE). No change in thalamic metabolism was disclosed. Altered functional connectivity was found between hyper- and hypometabolic regions in CSWS patients compared with pediatric pseudo-controls. This study demonstrates hypometabolism in key nodes of the default mode network (DMN) in awake patients with CSWS, in relation with a possible phenomenon of sustained remote inhibition from the epileptic foci. This hypometabolism might account for some of the acquired cognitive or behavioral features of CSWS epileptic encephalopathies. This study failed to find any evidence of thalamic metabolic changes, which supports the primary involvement of the cortex in CSWS genesis.

Reporting the ink color of a written word when it is itself a color name incongruent with the ink color (e.g. "red" printed in blue) induces a robust interference known as the Stroop effect. Although this effect has been the subject of numerous functional neuroimaging studies, its neuronal substrate is still a matter of debate. Here, we investigated the spatiotemporal dynamics of interference-related neural events using magnetoencephalography (MEG) and voxel-based analyses (SPM8). Evoked magnetic fields (EMFs) were acquired in 12 right-handed healthy subjects performing a color-word Stroop task. Behavioral results disclosed a classic interference effect with longer mean reaction times for incongruent than congruent stimuli. At the group level, EMFs' differences between incongruent and congruent trials spanned from 380 to 700 ms post-stimulus onset. Underlying neural sources were identified in the left pre-supplementary motor area (pre-SMA) and in the left posterior parietal cortex (PPC) confirming the role of these regions in conflict processing., JOURNAL ARTICLE, SCOPUS: ar.j, info:eu-repo/semantics/published

Background The treatment of refractory status epilepticus (RSE) remains largely empirical. Lacosamide (LCM) is a new anticonvulsant available in intravenous (IV) form, but its optimal dosing regimen for the treatment of RSE is unknown. We compared safety and efficacy of two loading doses: 200 and 400 mg. Methods Prospective observational study of all patients who received IV LCM for RSE or seizure clusters between October 2010 and December 2012. A first group received an IV load of 200 mg of LCM. After the initial part of the study, and due to poor results with this dosage, a second group received a loading dose of 400 mg. Outcome measures included response rate, time to response, and adverse events. Results There was a trend in favor of a higher response rate to LCM in the 400 mg group [7/14 (50 %) vs. 2/11 (18 %), respectively; p = 0.2]. Early responses (occurring within 3 h of initiation of LCM) were significantly more frequent in the 400 mg group [4/14 (28 %) vs. 0/11 (0 %); p = 0.026]. Overall, 9/25 patients (36 %) responded to LCM and seizures were terminated in eight more patients (32 %), by adding other anticonvulsants. The following adverse events were attributed to LCM: myoclonus and confusion, increase in seizure frequency, vertigo, ataxia, and an asymptomatic increase in liver enzymes level. All occurred in the 200 mg group. No skin rash, renal, cardiac, or hemodynamic side effects were observed in any group. Conclusions In this small prospective observational study, an initial dose of 400 mg of IV LCM was associated with a higher proportion of early termination of RSE and with a trend toward a higher response rate.

Epileptic syndromes with continuous spikes and waves during sleep (CSWS) are characterized by an acute phase with the emergence of psychomotor deficits and CSWS activity and by a recovery phase in which patients' clinical condition improves together with the remission of CSWS activity. The pathophysiological mechanisms of how CSWS activity induces psychomotor regression are still poorly understood. PET studies using [18F]-fluorodeoxyglucose (FDG) were performed in 9 children during acute and recovery phases of CSWS. PET data were analyzed at individual and group levels using statistical parametric mapping via subtractive, exclusive masking and variance analyses. Pathophysiological interaction analyses were conducted to determine the evolution of changes in effective connectivity between hypermetabolic and hypometabolic brain areas. At the individual level, CSWS recovery was characterized by a complete or almost complete regression of both hypermetabolic and hypometabolic abnormalities observed during the acute phase. Similar evolution was observed at the group level. Indeed, altered effective connectivity between focal hypermetabolism (centro-parietal regions and right fusiform gyrus) and widespread hypometabolism (prefrontal and orbitofrontal cortices, temporal lobes, left parietal cortex, precuneus and cerebellum) was found at the acute phase and markedly regressed at recovery. This study shows that the neurophysiological effects of CSWS activity are not restricted to the epileptic foci but spread via the inhibition of remote neurons within connected brain areas. The present study suggests that these reversible remote effects participate to the psychomotor repercussions of CSWS activity.

Metabolic changes have been described in the nonepileptic temporal lobe of patients with unilateral mesiotemporal lobe epilepsy (MTLE) associated with hippocampal sclerosis (HS). To better understand the functional correlate of this metabolic finding, we have sought to characterize brain regions in patients with MTLE that show correlation between unilateral episodic memory performances, as assessed by intracarotid amobarbital test (IAT), and interictal regional cerebral metabolism measured by [(18) F]-fluorodeoxyglucose positron emission tomography (FDG-PET).Resting FDG-PET was performed interictally in 26 patients with unilateral MTLE caused by HS (16 female, mean age: 36 years; 16 left HS). Using statistical parametric mapping (SPM8), we performed a group comparison analysis comparing brain metabolism in the patients and in 54 adult controls (27 female, mean age: 32 years), with FDG-PET data of right HS patients being flipped. IAT scores of nonepileptic hemisphere functions (amobarbital injection ipsilateral to HS) were used as covariates of interest in a correlation analysis with regional brain metabolism.The group comparison analysis revealed significant hypometabolic areas in a widespread temporofrontal network ipsilateral to HS. In addition, a significant increase in metabolism was found in mesial and lateral temporal regions contralateral to HS. Significant positive correlations were found between IAT scores of nonepileptic hemisphere functions and mesial temporal metabolism in this hemisphere.This study demonstrates the existence of significant increase in relative regional cerebral glucose metabolism in mesial and lateral temporal regions contralateral to the epileptic focus in patients with unilateral MTLE associated with HS. The positive correlation in these brain regions between IAT scores and metabolism supports the role of disease-induced plasticity mechanisms contralateral to HS in the preservation of episodic memory processes.

Positron emission tomography with O-15-labeled water was used to study at rest the neurophysiological effects of bilateral external globus pallidus (GPe) deep brain stimulation in patients with Huntington's disease (HD). Five patients were compared with a control group in the on and off states of the stimulator. External globus pallidus stimulation decreased neuronal activity and modulated cerebral connectivity within the basal ganglia-thalamocortical circuitry, the sensorimotor, and the default-mode networks. These data indicate that GPe stimulation modulates functional integration in HD patients in accordance with the basal ganglia-thalamocortical circuit model., Journal Article, Research Support, Non-U.S. Gov't, SCOPUS: ar.j, info:eu-repo/semantics/published

We studied online coupling between a reader's voice and a listener's cortical activity using a novel, ecologically valid continuous listening paradigm. Whole‐scalp magnetoencephalographic (MEG) signals were recorded from 10 right‐handed, native French‐speaking listeners in four conditions: a female (Exp1f) and a male (Exp1m) reading the same text in French; a male reading a text in Finnish (Exp 2), a language incomprehensible for the subjects, and a male humming Exp1 text (Exp 3). The fundamental frequency (f0) of the reader's voice was recorded with an accelerometer attached to the throat, and coherence was computed between f0 time‐course and listener's MEG. Similar levels of right‐hemisphere‐predominant coherence were found at ˜0.5 Hz in Exps 1–3. Dynamic imaging of coherent sources revealed that the most coherent brain regions were located in the right posterior superior temporal sulcus (pSTS) and posterior superior temporal gyrus (pSTG) in Exps 1–2 and in the right supratemporal auditory cortex in Exp 3. Comparison between speech rhythm and phrasing suggested a connection of the observed coherence to pauses at the sentence level both in the spoken and hummed text. These results demonstrate significant coupling at ∼0.5 Hz between reader's voice and listener's cortical signals during listening to natural continuous voice. The observed coupling suggests that voice envelope fluctuations, due to prosodic rhythmicity at the phrasal and sentence levels, are reflected in the listener's cortex as rhythmicity of about 2‐s cycles. The predominance of the coherence in the right pSTS and pSTG suggests hemispherical asymmetry in processing of speech sounds at subsentence time scales. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.