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1.
J Neuroinflammation ; 19(1): 104, 2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35488354

RESUMEN

BACKGROUND: Metabolic syndrome (MS) is defined as a low-grade proinflammatory state in which abnormal metabolic and cardiovascular factors increase the risk of developing cardiovascular disease and neuroinflammation. Events, such as the accumulation of visceral adipose tissue, increased plasma concentrations of free fatty acids, tissue hypoxia, and sympathetic hyperactivity in MS may contribute to the direct or indirect activation of Toll-like receptors (TLRs), specifically TLR4, which is thought to be a major component of this syndrome. Activation of the innate immune response via TLR4 may contribute to this state of chronic inflammation and may be related to the neuroinflammation and neurodegeneration observed in MS. In this study, we investigated the role of TLR4 in the brain microcirculation and in the cognitive performance of high-fat diet (HFD)-induced MS mice. METHODS: Wild-type (C3H/He) and TLR4 mutant (C3H/HeJ) mice were maintained under a normal diet (ND) or a HFD for 24 weeks. Intravital video-microscopy was used to investigate the functional capillary density, endothelial function, and endothelial-leukocyte interactions in the brain microcirculation. Plasma concentrations of monocyte chemoattractant protein-1 (MCP-1), adipokines and metabolic hormones were measured with a multiplex immunoassay. Brain postsynaptic density protein-95 and synaptophysin were evaluated by western blotting; astrocytic coverage of the vessels, microglial activation and structural capillary density were evaluated by immunohistochemistry. RESULTS: The HFD-induced MS model leads to metabolic, hemodynamic, and microcirculatory alterations, as evidenced by capillary rarefaction, increased rolling and leukocyte adhesion in postcapillary venules, endothelial dysfunction, and less coverage of astrocytes in the vessels, which are directly related to cognitive decline and neuroinflammation. The same model of MS reproduced in mice deficient for TLR4 because of a genetic mutation does not generate such changes. Furthermore, the comparison of wild-type mice fed a HFD and a normolipid diet revealed differences in inflammation in the cerebral microcirculation, possibly related to lower TLR4 activation. CONCLUSIONS: Our results demonstrate that TLR4 is involved in the microvascular dysfunction and neuroinflammation associated with HFD-induced MS and possibly has a causal role in the development of cognitive decline.


Asunto(s)
Disfunción Cognitiva , Síndrome Metabólico , Animales , Disfunción Cognitiva/complicaciones , Dieta Alta en Grasa/efectos adversos , Inflamación/metabolismo , Síndrome Metabólico/etiología , Ratones , Ratones Endogámicos C3H , Microcirculación , Mutación , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo
2.
Muscle Nerve ; 66(3): 304-311, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35661382

RESUMEN

INTRODUCTION/AIMS: Recent guidelines define chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and possible CIDP. The aims of our study were to evaluate the value of diagnostic tests to support the diagnosis of CIDP in patients with possible CIDP and to identify prognostic factors of therapeutic success. METHODS: We conducted an observational retrospective two-center study between 2014 and 2019. We selected patients with a clinical presentation suggesting CIDP, but whose electrodiagnostic (EDX) test results did not meet the EFNS/PNS 2021 criteria. We analyzed epidemiologic and clinical features, axonal loss on EDX, cerebrospinal fluid (CSF), somatosensory evoked potentials (SSEPs), plexus magnetic resonance imaging (MRI), nerve biopsy, and therapeutic response. RESULTS: We selected 75 patients, among whom 30 (40%) responded to treatment. The positivity rates of CSF analysis, MRI and SSEPs were not influenced by the clinical presentation or by the delay between symptom onset and medical assessment. A high protein level in CSF, female gender, and a relapsing-remitting course predicted the therapeutic response. DISCUSSION: It is important to properly diagnose suspected CIDP not meeting EFNS/PNS 2021 EDX criteria by using supportive criteria. Specific epidemiological factors and a raised CSF protein level predict a response to treatment. Further prospective studies are needed to improve diagnosis and the prognostic value of diagnostic tests in CIDP.


Asunto(s)
Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante , Pruebas Diagnósticas de Rutina , Femenino , Humanos , Imagen por Resonancia Magnética , Polirradiculoneuropatía Crónica Inflamatoria Desmielinizante/terapia , Pronóstico , Estudios Retrospectivos
3.
Epilepsia ; 60(8): 1508-1525, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31283859

RESUMEN

Accumulating data on patients with autoimmune encephalitis have shed light on specificities concerning clinical presentation and outcomes, which are dependent on the antigen targeted by the autoantibodies found in the patients' cerebrospinal fluid or sera. Such specificities include seizure-related clinical manifestations as well as the responsiveness to antiepileptic drugs. Although increased enthusiasm accompanies the discovery of novel antibodies and their associated clinical syndromes, several issues remain unsettled. First, it appears that therapy needs to be personalized in the view of the severity of each antibody-mediated syndrome, patient-related characteristics, and timing of treatment. Second, the lack of randomized controlled trials is a major drawback in the formulation of an appropriate immunotherapeutic strategy. In this review, we discuss the novel developments and challenges for the diagnosis and treatment of epilepsy in patients with well-characterized autoimmune encephalitis, and delineate the principles for a rational approach toward precision medicine in this emerging field.


Asunto(s)
Encefalitis/fisiopatología , Enfermedad de Hashimoto/fisiopatología , Convulsiones/fisiopatología , Autoanticuerpos/inmunología , Humanos , Convulsiones/diagnóstico , Convulsiones/inmunología
4.
BMC Neurosci ; 18(1): 67, 2017 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-28886695

RESUMEN

BACKGROUND: Metabolic syndrome (MetS) is associated with an increased risk of cerebrovascular diseases, including cerebral ischemia. Microvascular dysfunction is an important feature underlying the pathophysiology of cerebrovascular diseases. In this study, we aimed to investigate the impacts of ischemia and reperfusion (IR) injury on the cerebral microvascular function of rats with high-fat diet-induced MetS. RESULTS: We examined Wistar rats fed a high-fat diet (HFD) or normal diet (CTL) for 20 weeks underwent 30 min of bilateral carotid artery occlusion followed by 1 h of reperfusion (IR) or sham surgery. Microvascular blood flow was evaluated on the parietal cortex surface through a cranial window by laser speckle contrast imaging, functional capillary density, endothelial function and endothelial-leukocyte interactions by intravital videomicroscopy. Lipid peroxidation was assessed by TBARs analysis, the expression of oxidative enzymes and inflammatory markers in the brain tissue was analyzed by real-time PCR. The cerebral IR in MetS animals induced a functional capillary rarefaction (HFD IR 117 ± 17 vs. CTL IR 224 ± 35 capillary/mm2; p < 0.05), blunted the endothelial response to acetylcholine (HFD IR -16.93% vs. CTL IR 16.19% from baseline inner diameter p < 0.05) and increased the endothelial-leukocyte interactions in the venules in the brain. The impact of ischemia on the cerebral microvascular blood flow was worsened in MetS animals, with a marked reduction of cerebral blood flow, exposing brain tissue to a higher state of hypoxia. CONCLUSIONS: Our results demonstrate that during ischemia and reperfusion, animals with MetS are more susceptible to alterations in the cerebral microcirculation involving endothelial dysfunction and oxidative stress events.


Asunto(s)
Isquemia Encefálica/fisiopatología , Dieta Alta en Grasa , Síndrome Metabólico/fisiopatología , Daño por Reperfusión/fisiopatología , Animales , Circulación Cerebrovascular/fisiología , Microcirculación/fisiología , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reperfusión/métodos
5.
Hum Brain Mapp ; 37(11): 3767-3778, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27312488

RESUMEN

BACKGROUND: Paired-pulse (PP) paradigms are commonly employed to assess in vivo cortical excitability using transcranial magnetic stimulation (TMS) to stimulate the primary motor cortex and modulate the induced motor evoked potential (MEP). Single-pulse cortical direct electrical stimulation (DES) during intracerebral EEG monitoring allows the investigation of brain connectivity by eliciting cortico-cortical evoked potentials (CCEPs). However, PP paradigm using intracerebral DES has rarely been reported and has never been previously compared with TMS. OBJECTIVE: The work was intended (i) to verify that the well-established modulations of MEPs following PP TMS remain similar using DES in the motor cortex, and (ii) to evaluate if a similar pattern could be observed in distant cortico-cortical connections through modulations of CCEP. METHODS: Three patients undergoing intracerebral EEG monitoring with electrodes implanted in the central region were studied. Single-pulse DES (1-3 mA, 1 ms, 0.2 Hz) and PP DES using six interstimulus intervals (5, 15, 30, 50, 100, and 200 ms) in the motor cortex with concomitant recording of CCEPs and MEPs in contralateral muscles were performed. Finally, a navigated PP TMS session targeted the intracranial stimulation site to record TMS-induced MEPs in two patients. RESULTS: MEP modulations elicited by PP intracerebral DES proved similar among the three patients and to those obtained by PP TMS. CCEP modulations elicited by PP intracerebral DES usually showed a pattern comparable to that of MEP, although a different pattern could be observed occasionally. CONCLUSION: PP intracerebral DES seems to involve excitatory and inhibitory mechanisms similar to PP TMS and allows the recording of intracortical inhibition and facilitation modulation on cortico-cortical connections. Hum Brain Mapp 37:3767-3778, 2016. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Corteza Cerebral/fisiología , Estimulación Eléctrica , Electrocorticografía , Potenciales Evocados Motores/fisiología , Estimulación Magnética Transcraneal , Adulto , Corteza Cerebral/fisiopatología , Epilepsia Refractaria/fisiopatología , Epilepsias Parciales/fisiopatología , Humanos , Masculino , Músculo Esquelético/fisiología , Adulto Joven
6.
Cancers (Basel) ; 16(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38927899

RESUMEN

Surgery for spinal cord tumors poses a significant challenge due to the inherent risk of neurological deterioration. Despite being performed at numerous centers, there is an ongoing debate regarding the efficacy of pre- and intraoperative neurophysiological investigations in detecting and preventing neurological lesions. This study begins by providing a comprehensive review of the neurophysiological techniques commonly employed in this context. Subsequently, we present findings from a cohort of 67 patients who underwent surgery for intradural tumors. These patients underwent preoperative and intraoperative multimodal somatosensory evoked potentials (SSEPs) and motor evoked potentials (MEPs), with clinical evaluation conducted three months postoperatively. The study aimed to evaluate the neurophysiological, clinical, and radiological factors associated with neurological outcomes. In univariate analysis, preoperative and intraoperative potential alterations, tumor size, and ependymoma-type histology were linked to the risk of worsening neurological condition. In multivariate analysis, only preoperative and intraoperative neurophysiological abnormalities remained significantly associated with such neurological deterioration. Interestingly, transient alterations in intraoperative MEPs and SSEPs did not pose a risk of neurological deterioration. The machine learning model we utilized demonstrated the possibility of predicting clinical outcome, achieving 84% accuracy.

7.
Cancers (Basel) ; 16(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39199605

RESUMEN

This pilot study aimed to investigate the interest of high angular resolution diffusion imaging (HARDI) and tractography of the spinal cord (SC) in the management of patients with intramedullary tumors by providing predictive elements for tumor resection. Eight patients were included in a prospective study. HARDI images of the SC were acquired using a 3T MRI scanner with a reduced field of view. Opposed phase-encoding directions allowed distortion corrections. SC fiber tracking was performed using a deterministic approach, with extraction of tensor metrics. Then, regions of interest were drawn to track the spinal pathways of interest. HARDI and tractography added value by providing characteristics about the microstructural organization of the spinal white fibers. In patients with SC tumors, tensor metrics demonstrated significant changes in microstructural architecture, axonal density, and myelinated fibers (all, p < 0.0001) of the spinal white matter. Tractography aided in the differentiation of tumor histological types (SC-invaded vs. pushed back by the tumor), and differentiation of the spinal tracts enabled the determination of precise anatomical relationships between the tumor and the SC, defining the tumor resectability. This study underlines the value of using HARDI and tractography in patients with intramedullary tumors, to show alterations in SC microarchitecture and to differentiate spinal tracts to establish predictive factors for tumor resectability.

8.
Ann Clin Transl Neurol ; 11(3): 826-836, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38263791

RESUMEN

OBJECTIVE: Central pontine myelinolysis (CPM) is a rare demyelinating disease that affects the pons and which can cause extreme disabilities such as locked-in syndrome (LIS) in the initial phase. The aim of the study was to describe the evolution over a 12-month period of two patients with CPM causing an initial LIS. METHOD: We retrospectively report the unexpected clinical outcome of these two patients in relation with the anatomical damages documented by brain MRI, associated with diffusion tensor imaging and reconstruction of corticospinal tracts in tractography. The following clinical parameters systematically assessed at 3, 6, 9, and 12 months: muscle testing on 12 key muscles (Medical Research Council), prehension metrics (box and block test and purdue pegboard), and independence for acts of daily living (functional independence measure). RESULTS: Both patients showed a progressive recovery beginning between 2 and 3 months after the onset of symptoms, leading to almost complete autonomy at 12 months (FIM > 110), with motor strength greater than 4/5 in all joint segments (MRC > 50/60). On brain MRI with tractography, CST appeared partially preserved at pons level. INTERPRETATION: The possibility of a near-complete functional recovery at 12 months is important to consider given the ethical issues at stake and the discussions about limiting care that may take place initially. It seems to be the consequence of reversible myelin damage combined with partially preserved neurons. Development of collateral pathways or resolution of conduction block may explain this recovery. MRI comprising DTI and tractography could play a key role in the prognosis of motor recovery.


Asunto(s)
Síndrome de Enclaustramiento , Mielinólisis Pontino Central , Humanos , Mielinólisis Pontino Central/diagnóstico por imagen , Mielinólisis Pontino Central/etiología , Imagen de Difusión Tensora , Estudios Retrospectivos , Tractos Piramidales/diagnóstico por imagen
9.
Vaccine ; 42(21): 126160, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39068066

RESUMEN

BACKGROUND: Influenza vaccines are effective in decreasing hospitalizations and mortality related to influenza and its complications. However, the Vaccine Coverage Rate of influenza remains low and multifaceted efforts are required to improve it. The aim of this study was to assess the impact on influenza vaccine perception using a digital tool among outpatients and health care workers (HCWs). METHODS: A study was performed among outpatients and the HCWs of 23 hospital departments from 4 hospitals affiliated to Lyon university Hospitals (France), between October 2022 and February 2023. By scanning QR (Quick Response) codes, displayed on posters for patients, their companions, as well as in the letters sent to HCWs, users accessed anonymously to a web-application (ELEFIGHT®), which provided information on influenza and invited them to initiate a discussion on influenza prevention with their physicians during the consultation. Patients were also invited to complete a questionnaire regarding their perception of influenza vaccination before and after reading the information on ELEFIGHT®. The retention rate (RR = proportion of people who remain on the page for >2 s), the conversion rate (CR = proportion of people who click on the "Call-To-Action" button) and the absolute variation (difference in the perception before/after) and relative variation (absolute change as a percentage of the initial perception) in perception regarding influenza vaccination before and after consulting the application were calculated. RESULTS: 3791 scans were performed by 3298 patients and/or their companions with a RR of 52% and a CR of 55.1% and 253 scans by 221 HCWs with a RR of 71.2% and a CR of 115.3%. Participants spent an average of 47 s on the application. The questionnaire on influenza vaccination perception was completed by 1533 participants (46.5%); 1390 (90.7%) maintained the same position (neutral, favorable or unfavorable) on this vaccination before and after consulting the application. The relative variations in favor of vaccination were + 7.2% (unfavorable then favorable) and + 19.8% (neutral then favorable). CONCLUSION: This study suggests that a facilitated direct access to medical information through QR codes disseminated in health settings can help nudge people to foster their awareness of influenza and its prevention. Future deployments in a similar context or to other populations could be envisaged. Other vaccine-preventable and/or chronic diseases could also be the target of similar projects as part of public health programs.


Asunto(s)
Hospitales Universitarios , Vacunas contra la Influenza , Gripe Humana , Humanos , Gripe Humana/prevención & control , Masculino , Femenino , Vacunas contra la Influenza/administración & dosificación , Vacunas contra la Influenza/inmunología , Persona de Mediana Edad , Adulto , Encuestas y Cuestionarios , Estudios Prospectivos , Francia/epidemiología , Vacunación/estadística & datos numéricos , Vacunación/psicología , Personal de Salud/estadística & datos numéricos , Anciano , Adulto Joven , Conocimientos, Actitudes y Práctica en Salud , Acceso a la Información , Adolescente , Pacientes Ambulatorios/estadística & datos numéricos
10.
Microvasc Res ; 87: 41-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23466285

RESUMEN

We examined the functional and structural microcirculatory alterations in the brain, skeletal muscle and myocardium of non-diabetic spontaneously hypertensive rats (SHR) and diabetic SHR (D-SHR), as well as the effects of long-term treatment with the angiotensin AT1-receptor antagonist olmesartan and the angiotensin-converting enzyme inhibitor enalapril. Diabetes was experimentally induced by a combination of a high-fat diet with a single low dose of streptozotocin (35 mg/kg, intraperitoneal injection). D-SHR were orally administered with olmesartan (5 mg/kg/day), enalapril (10 mg/kg/day) or vehicle for 28 days, and compared with vehicle-treated non-diabetic SHR or normotensive non-diabetic Wistar-Kyoto rats. The cerebral and skeletal muscle functional capillary density of pentobarbital-anesthetized rats was assessed using intravital fluorescence videomicroscopy. Chronic treatment with olmesartan or enalapril significantly lowered blood pressure and reversed brain functional capillary rarefaction. Brain oxidative stress was reduced to non-diabetic control levels in animals treated with olmesartan or enalapril. Histochemical analysis of the structural capillary density showed that both olmesartan and enalapril increased the capillary-to-fiber ratio in skeletal muscle and the capillary-to-fiber volume density in the left ventricle. Olmesartan and enalapril also prevented collagen deposition and the increase in cardiomyocyte diameter in the left ventricle. Our results suggest that the association between hypertension and diabetes results in microvascular alterations in the brain, skeletal muscle and myocardium that can be prevented by chronic blockade of the renin-angiotensin system.


Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Antihipertensivos/farmacología , Encéfalo/irrigación sanguínea , Circulación Cerebrovascular/efectos de los fármacos , Trastornos Cerebrovasculares/tratamiento farmacológico , Diabetes Mellitus Experimental/tratamiento farmacológico , Angiopatías Diabéticas/tratamiento farmacológico , Enalapril/farmacología , Hipertensión/tratamiento farmacológico , Imidazoles/farmacología , Microcirculación/efectos de los fármacos , Sistema Renina-Angiotensina/efectos de los fármacos , Tetrazoles/farmacología , Animales , Presión Arterial/efectos de los fármacos , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Encéfalo/metabolismo , Capilares/efectos de los fármacos , Capilares/fisiopatología , Trastornos Cerebrovasculares/etiología , Trastornos Cerebrovasculares/metabolismo , Trastornos Cerebrovasculares/fisiopatología , Circulación Coronaria/efectos de los fármacos , Diabetes Mellitus Experimental/etiología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatología , Angiopatías Diabéticas/etiología , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/fisiopatología , Dieta Alta en Grasa , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/metabolismo , Ventrículos Cardíacos/patología , Hipertensión/complicaciones , Hipertensión/metabolismo , Hipertensión/fisiopatología , Insulina/sangre , Rodamiento de Leucocito/efectos de los fármacos , Masculino , Microscopía Fluorescente , Microscopía por Video , Músculo Esquelético/irrigación sanguínea , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Endogámicas SHR , Ratas Endogámicas WKY , Estreptozocina
11.
Front Hum Neurosci ; 17: 1167489, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37425290

RESUMEN

Introduction: We report a very unique clinical presentation of a patient who complained, after a left parietal brain damage, about feeling tactile stimulations on his right upper limb without being able to localize them. Methods: Using a single case study approach, we report three experiments relying on several custom-made tasks to explore the different levels of somatosensory information processing, ranging from somato-sensation to somato-representation. Results: Our results showed a preserved ability to localize tactile stimuli applied on the right upper limb when using pointing responses while the ability to localize was less efficient when having to name the stimulated part (akin Numbsense). When the stimuli were applied on more distal locations (i.e., on the hand and on fingers), the number of correct responses decreased significantly independently of the modality of response. Finally, when visually presented with a stimulus delivered on the hand of an examiner in synchrony with the stimulation on the hidden hand of the patient, responses were largely influenced by the visual information available. Altogether, the convergence of these different customized tasks revealed an absence of autotopagnosia for motor responses for the right upper limb, associated with altered abilities to discriminate stimulus applied on distal and restricted/closer zones in the hand. Discussion: The somato-representation of our patient seemed to significantly rely on visual information, leading to striking deficits to localize tactile stimuli when vision and somesthesic afferences are discordant. This case report offers a clinical illustration of pathological imbalance between vision and somesthesia. Implications of these troubles in somato-representation on higher cognitive level processes are discussed.

12.
Neurotherapeutics ; 20(1): 207-219, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36266501

RESUMEN

While high-frequency transcranial magnetic stimulation (HF-rTMS) is now included in the armamentarium to treat chronic neuropathic pain (NP), direct-current anodal stimulation (a-tDCS) to the same cortical targets may represent a valuable alternative in terms of feasibility and cost. Here we performed a head-to-head, randomized, single-blinded, cross-over comparison of HF-rTMS versus a-tDCS over the motor cortex in 56 patients with drug-resistant NP, who received 5 daily sessions of each procedure, with a washout of at least 4 weeks. Daily scores of pain, sleep, and fatigue were obtained during 5 consecutive weeks, and functional magnetic resonance imaging (fMRI) to a motor task was performed in a subgroup of 31 patients. The percentage of responders, defined by a reduction in pain scores of > 2 SDs from pre-stimulus levels, was similar to both techniques (42.0% vs. 42.3%), while the magnitude of "best pain relief" was significantly skewed towards rTMS. Mean pain ratings in responders decreased by 32.6% (rTMS) and 29.6% (tDCS), with half of them being sensitive to only one technique. Movement-related fMRI showed significant activations in motor and premotor areas, which did not change after 5 days of stimulation, and did not discriminate responders from non-responders. Both HF-rTMS and a-tDCS showed efficacy at 1 month in drug-resistant NP, with magnitude of relief slightly favoring rTMS. Since a significant proportion of patients responded to one procedure only, both modalities should be tested before declaring a patient as unresponsive.


Asunto(s)
Corteza Motora , Neuralgia , Estimulación Transcraneal de Corriente Directa , Humanos , Neuralgia/terapia , Manejo del Dolor/métodos , Estimulación Transcraneal de Corriente Directa/métodos , Estimulación Magnética Transcraneal/métodos
13.
Clin Neurophysiol ; 145: 151-161, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36328928

RESUMEN

OBJECTIVE: Early functional evaluation and prognosis of patients with disorders of consciousness is a major challenge that clinical assessments alone cannot solve. Objective measures of brain activity could help resolve this uncertainty. We used electroencephalogram at bedside to detect voluntary attention with a paradigm previously validated in healthy subjects. METHODS: Using auditory-oddball sequences, our approach rests on detecting known attentional modulations of Event Related Potentials that reflect compliance with verbal instructions. Sixty-eight unresponsive patients were tested in their first year after coma onset (37 coma and 31 first year post-coma patients). Their evolution 6 months after the test was considered. RESULTS: Fourteen of the 68 patients, showed a positive response. Nine were in a coma and 5 in a minimally conscious state (MCS). Except for one who died early, all responders evolved to exit-MCS within 6 months (93%), while 35 (65%) among non-responders only. CONCLUSIONS: Among those patients for whom the outcome is highly uncertain, 21% responded positively to this simple but cognitively demanding test. Strikingly, some coma patients were among responders. SIGNIFICANCE: The proposed paradigm revealed cognitive-motor dissociation in some coma patients. This ability to sustain attention on demand predicted awakening within 6 months and represents an immediately useful information for relatives and caregivers.


Asunto(s)
Coma , Estado Vegetativo Persistente , Humanos , Coma/diagnóstico , Estado Vegetativo Persistente/diagnóstico , Electroencefalografía , Atención , Pronóstico , Electrofisiología
15.
Neurophysiol Clin ; 52(3): 242-251, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35396150

RESUMEN

OBJECTIVES: To assess the accuracy of intraoperative neurophysiological monitoring (IONM) in predicting immediate and 3-month postoperative neurological new deficit (or deterioration) in patients benefiting from spinal cord (SC) surgery; and to identify factors associated with a higher risk of postoperative clinical worsening. METHODS: Consecutive patients who underwent SC surgery with IONM were included. Pre and postoperative clinical (modified McCormick scale), radiological (lesion-occupying area ratio), and electrophysiological features were collected. RESULTS: A total of 99 patients were included: 14 (14.1%) underwent extradural surgery, 50 (50.5%) intradural extramedullary surgery, and 35 (35.4%) intramedullary surgery. Cumulatively, multimodal IONM (motor and somatosensory evoked potentials, D-wave whenever possible) significantly predicted postoperative deficits (p<0.001), with a sensitivity, specificity, positive predictive value, and negative predictive value of 0.81, 0.93, 0.83, and 0.92, respectively. Sixty (60.6%) patients displayed no IONM change, whereas 39 (39.4%) displayed IONM worsening. In multivariate analysis, predictors for postoperative clinical worsening were: abnormal preoperative electrophysiological assessment (p=0.03), intramedullary tumor (p<0.001), lesion-occupying area ratio ≥0.7 (p<0.001), and IONM alterations (p<0.001). Three months after the surgical procedure, in patients presenting at least one of the risk factors described above, 45/81 (55.6%) and 19/81 (23.5%) were clinically and electrophysiologically improved, respectively; while 13/81 (16.0%) and 10/81 (12.3%) were clinically and electrophysiologically worsened. CONCLUSION: Multimodal IONM is an essential tool to guide SC surgery, and enables the accurate prediction of postoperative neurological outcome. Specific attention should be given to patients presenting with preoperative electrophysiological abnormalities, large tumor volume, and intramedullary tumor location.


Asunto(s)
Monitorización Neurofisiológica Intraoperatoria , Neoplasias de la Médula Espinal , Potenciales Evocados Motores/fisiología , Humanos , Monitorización Neurofisiológica Intraoperatoria/métodos , Imagen por Resonancia Magnética , Estudios Retrospectivos , Neoplasias de la Médula Espinal/cirugía
16.
Clin Neurophysiol ; 135: 154-161, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35093702

RESUMEN

OBJECTIVE: The acoustic characteristics of stimuli influence the characteristics of the corresponding evoked potentials in healthy subjects. Own-name stimuli are used in clinical practice to assess the level of consciousness in intensive care units. The influence of the acoustic variability of these stimuli has never been evaluated. Here, we explored the influence of this variability on the characteristics of the subject's own name (SON) P300. METHODS: We retrospectively analyzed 251 disorders of consciousness patients from Lyon and Paris Hospitals who underwent an "own-name protocol". A reverse correlation analysis was performed to test for an association between acoustic properties of own-names stimuli used and the characteristics of the P300 wave observed. RESULTS: Own-names pronounced with increasing pitch prosody showed P300 responses 66 ms earlier than own-names that had a decreasing prosody [IC95% = 6.36; 125.9 ms]. CONCLUSIONS: Speech prosody of the stimuli in the "own name protocol" is associated with latencies differences of the P300 response among patients for whom these responses were observed. Further investigations are needed to confirm these results. SIGNIFICANCE: Speech prosody of the stimuli in the "own name protocol" is a non-negligible parameter, associated with P300 latency differences. Speech prosody should be standardized in SON P300 studies.


Asunto(s)
Coma/fisiopatología , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300 , Percepción del Habla , Coma/diagnóstico , Electroencefalografía/normas , Femenino , Humanos , Masculino , Semántica , Acústica del Lenguaje
17.
Front Neurol ; 13: 804528, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35250813

RESUMEN

Most of motor recovery usually occurs within the first 3 months after stroke. Herein is reported a remarkable late recovery of the right upper-limb motor function after a left middle cerebral artery stroke. This recovery happened progressively, from two to 12 years post-stroke onset, and along a proximo-distal gradient, including dissociated finger movements after 5 years. Standardized clinical assessment and quantified analysis of the reach-to-grasp movement were repeated over time to characterize the recovery. Twelve years after stroke onset, diffusion tensor imaging (DTI), functional magnetic resonance imaging (fMRI), and transcranial magnetic stimulation (TMS) analyses of the corticospinal tracts were carried out to investigate the plasticity mechanisms and efferent pathways underlying motor control of the paretic hand. Clinical evaluations and quantified movement analysis argue for a true neurological recovery rather than a compensation mechanism. DTI showed a significant decrease of fractional anisotropy, associated with a severe atrophy, only in the upper part of the left corticospinal tract (CST), suggesting an alteration of the CST at the level of the infarction that is not propagated downstream. The finger opposition movement of the right paretic hand was associated with fMRI activations of a broad network including predominantly the contralateral sensorimotor areas. Motor evoked potentials were normal and the selective stimulation of the right hemisphere did not elicit any response of the ipsilateral upper limb. These findings support the idea that the motor control of the paretic hand is mediated mainly by the contralateral sensorimotor cortex and the corresponding CST, but also by a plasticity of motor-related areas in both hemispheres. To our knowledge, this is the first report of a high quality upper-limb recovery occurring more than 2 years after stroke with a genuine insight of brain plasticity mechanisms.

18.
Lancet Neurol ; 21(9): 781-791, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35963261

RESUMEN

BACKGROUND: The incidence of early seizures (occurring within 7 days of stroke onset) after intracerebral haemorrhage reaches 30% when subclinical seizures are diagnosed by continuous EEG. Early seizures might be associated with haematoma expansion and worse neurological outcomes. Current guidelines do not recommend prophylactic antiseizure treatment in this setting. We aimed to assess whether prophylactic levetiracetam would reduce the risk of acute seizures in patients with intracerebral haemorrhage. METHODS: The double-blind, randomised, placebo-controlled, phase 3 PEACH trial was conducted at three stroke units in France. Patients (aged 18 years or older) who presented with a non-traumatic intracerebral haemorrhage within 24 h after onset were randomly assigned (1:1) to levetiracetam (intravenous 500 mg every 12 h) or matching placebo. Randomisation was done with a web-based system and stratified by centre and National Institutes of Health Stroke Scale (NIHSS) score at baseline. Treatment was continued for 6 weeks. Continuous EEG was started within 24 h after inclusion and recorded over 48 h. The primary endpoint was the occurrence of at least one clinical seizure within 72 h of inclusion or at least one electrographic seizure recorded on continuous EEG, analysed in the modified intention-to-treat population, which comprised all patients who were randomly assigned to treatment and who had a continuous EEG performed. This trial was registered at ClinicalTrials.gov, NCT02631759, and is now closed. Recruitment was prematurely stopped after 48% of the recruitment target was reached due to a low recruitment rate and cessation of funding. FINDINGS: Between June 1, 2017, and April 14, 2020, 50 patients with mild-to-moderate severity intracerebral haemorrhage were included: 24 were assigned to levetiracetam and 26 to placebo. During the first 72 h, a clinical or electrographic seizure was observed in three (16%) of 19 patients in the levetiracetam group versus ten (43%) of 23 patients in the placebo group (odds ratio 0·16, 95% CI 0·03-0·94, p=0·043). All seizures in the first 72 h were electrographic seizures only. No difference in depression or anxiety reporting was observed between the groups at 1 month or 3 months. Depression was recorded in three (13%) patients who received levetiracetam versus four (15%) patients who received placebo, and anxiety was reported for two (8%) patients versus one (4%) patient. The most common treatment-emergent adverse events in the levetiracetam group versus the placebo group were headache (nine [39%] vs six [24%]), pain (three [13%] vs ten [40%]), and falls (seven [30%] vs four [16%]). The most frequent serious adverse events were neurological deterioration due to the intracerebral haemorrhage (one [4%] vs four [16%]) and severe pneumonia (two [9%] vs two [8%]). No treatment-related death was reported in either group. INTERPRETATION: Levetiracetam might be effective in preventing acute seizures in intracerebral haemorrhage. Larger studies are needed to determine whether seizure prophylaxis improves functional outcome in patients with intracerebral haemorrhage. FUNDING: French Ministry of Health.


Asunto(s)
Epilepsia , Accidente Cerebrovascular , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/tratamiento farmacológico , Epilepsia/complicaciones , Humanos , Levetiracetam/efectos adversos , Convulsiones/complicaciones , Convulsiones/tratamiento farmacológico , Convulsiones/prevención & control , Accidente Cerebrovascular/tratamiento farmacológico , Resultado del Tratamiento , Estados Unidos
19.
Neurotherapeutics ; 16(4): 1198-1209, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31062295

RESUMEN

The clinical use of noninvasive cortical stimulation procedures is hampered by the limited duration of the analgesic effects and the need to perform stimulation in hospital settings. Here, we tested the feasibility and pilot efficacy of an internet-based system for at-home, long-duration, medically controlled transcranial motor cortex stimulation (H-tDCS), via a double-blinded, sham-controlled trial in patients with neuropathic pain refractory to standard-of-care drug therapy. Each patient was first trained at hospital, received a stimulation kit, allotted a password-protected Web space, and completed daily tDCS sessions during 5 weeks, via a Bluetooth connection between stimulator and a minilaptop. Each session was validated and internet-controlled by hospital personnel. Daily pain ratings were obtained during 11 consecutive weeks, and afterwards via iterative visits/phone contacts. Twenty full procedures were completed in 12 consecutive patients (500 daily tDCS sessions, including 20% sham). No serious adverse effects were recorded. Superficial burning at electrode position occurred in 2 patients, and nausea/headache in two others, all of whom wished to pursue stimulation. Six out of the 12 patients achieved satisfactory relief on a scale combining pain scores, drug intake, and quality of life. Daily pain reports correlated with such combined assessment, and differentiated responders from nonresponders without overlap. Clinical improvement in responders could last up to 6 months. Five patients asked to repeat the whole procedure when pain resumed again, with comparable results. At-home, long-duration tDCS proved safe and technically feasible, and provided long-lasting relief in 50% of a small sample of patients with drug-resistant neuropathic pain.


Asunto(s)
Servicios de Atención de Salud a Domicilio , Corteza Motora/fisiología , Neuralgia/terapia , Manejo del Dolor/métodos , Dimensión del Dolor/métodos , Estimulación Transcraneal de Corriente Directa/métodos , Adulto , Anciano , Método Doble Ciego , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuralgia/diagnóstico , Manejo del Dolor/instrumentación , Autocuidado/instrumentación , Autocuidado/métodos , Estimulación Transcraneal de Corriente Directa/instrumentación
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