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1.
Br J Neurosurg ; 37(4): 741-744, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31130025

RESUMO

Flow-diverting stents (FD) are admitted therapeutic devices for challenging aneurysms. Delayed migrations of FD remain exceptional, particularly with brainstem compression. We report a case of delayed migration of pipeline embolization device (PED) responsible of medulla oblongata compression due to expansion of posterior inferior cerebellar artery (PICA) aneurysm. This is the first report of brainstem compression due to delayed migration of FD. Among the seven previously reported cases of FD delayed migration, two led to death. Our case illustrates the importance of technical issues of stenting and the role of surgery facing the clinical emergency of vascular compression of lower brainstem. We wanted to warn neurosurgeons of this rare and delayed complication, which likely could become less exceptional with the increase of indications and utilizations of FD.


Assuntos
Encefalopatias , Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/complicações , Procedimentos Endovasculares/efeitos adversos , Stents/efeitos adversos , Prótese Vascular , Tronco Encefálico/diagnóstico por imagem , Embolização Terapêutica/efeitos adversos , Resultado do Tratamento , Estudos Retrospectivos
2.
Ann Clin Transl Neurol ; 5(11): 1372-1384, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30480031

RESUMO

OBJECTIVE: The efficacy of deep brain stimulation in disorders of consciousness remains inconclusive. We investigated bilateral 30-Hz low-frequency stimulation designed to overdrive neuronal activity by dual pallido-thalamic targeting, using the Coma Recovery Scale Revised (CRS-R) to assess conscious behavior. METHODS: We conducted a prospective, single center, observational 11-month pilot study comprising four phases: baseline (2 months); surgery and titration (1 month); blind, random, crossover, 1.5-month ON and OFF periods; and unblinded, 5-month stimulation ON. Five adult patients were included: one unresponsive-wakefulness-syndrome male (traumatic brain injury); and four patients in a minimally conscious state, one male (traumatic brain injury) and three females (two hemorrhagic strokes and one traumatic brain injury). Primary outcome measures focused on CRS-R scores. Secondary outcome measures focused notably on baseline brain metabolism and variation in activity (stimulation ON - baseline) using normalized fluorodeoxyglucose positron emission tomography maps. Statistical analysis used random-effect models. RESULTS: The two male patients (one minimally conscious and one unresponsive wakefulness syndrome) showed improved mean CRS-R scores (stimulation ON vs. baseline), in auditory, visual and oromotor/verbal subscores, and visual subscores respectively. The metabolism of the medial cortices (low at baseline in all five patients) increased specifically in the two responders. INTERPRETATION: Our findings show there were robust but limited individual clinical benefits, mainly in visual and auditory processes. Overall modifications seem linked to the modulation of thalamo-cortico-basal and tegmental loops activating default mode network cortices. Specifically, in the two responders there was an increase in medial cortex activity related to internal awareness.

3.
Neuroimage ; 183: 37-46, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30053516

RESUMO

External information can modify the subjective value of a tasted stimulus, but little is known about neural mechanisms underlying these behavioral modifications. This study used flavored drinks to produce variable degrees of discrepancy between expected and received flavor. During a learning session, 43 healthy young men learned 4 symbol-flavor associations. In a separate session, associations were presented again during an fMRI scan, but half of the trials introduced discrepancy with previously learned associations. Liking ratings of drinks were collected and were analyzed using a linear model to define the degree to which discrepant symbols affected liking ratings of the subjects during the fMRI session. Based on these results, a GLM analysis of fMRI data was conducted to determine neural correlates of observed behavior. Groups of subjects were composed based on their behavior in response to discrepant symbols, and comparison of brain activity between groups showed that activation in the PCC and the caudate nucleus was more potent in those subjects in which liking was not affected by discrepant symbols. These activations were not found in subjects who assimilated unexpected flavors to flavors preceeded by discrepant symbols. Instead, these subjects showed differences in the activity in the parietal operculum. The activity of reward network appears to be related to assimilation of received flavor to expected flavor in response to symbol-flavor discrepancy.


Assuntos
Associação , Mapeamento Encefálico/métodos , Núcleo Caudado/fisiologia , Córtex Cerebral/fisiologia , Rede Nervosa/fisiologia , Recompensa , Percepção Gustatória/fisiologia , Percepção Visual/fisiologia , Adulto , Bebidas , Núcleo Caudado/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Sinais (Psicologia) , Humanos , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Adulto Jovem
4.
Lancet Neurol ; 17(4): 317-326, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29500154

RESUMO

BACKGROUND: Prediction of neurological outcome after cardiac arrest is a major challenge. The aim of this study was to assess whether quantitative whole-brain white matter fractional anisotropy (WWM-FA) measured by diffusion tensor imaging between day 7 and day 28 after cardiac arrest can predict long-term neurological outcome. METHODS: This prospective, observational, cohort study (part of the MRI-COMA study) was done in 14 centres in France, Italy, and Belgium. We enrolled patients aged 18 years or older who had been unconscious for at least 7 days after cardiac arrest into the derivation cohort. The following year, we recruited the validation cohort on the same basis. We also recruited a minimum of five healthy volunteers at each centre for the normalisation procedure. WWM-FA values were compared with standard criteria for unfavourable outcome, conventional MRI sequences (fluid-attenuated inversion recovery and diffusion-weighted imaging), and proton magnetic resonance spectroscopy. The primary outcome was the best achieved Glasgow-Pittsburgh Cerebral Performance Categories (CPC) at 6 months, dichotomised as favourable (CPC 1-2) and unfavourable outcome (CPC 3-5). Prognostication performance was assessed by the area under the receiver operating characteristic (ROC) curves and compared between groups. This study was registered with ClinicalTrials.gov, number NCT00577954. FINDINGS: Between Oct 1, 2006, and June 30, 2014, 185 patients were enrolled in the derivation cohort, of whom 150 had an interpretable multimodal MRI and were included in the analysis. 33 (22%) patients had a favourable neurological outcome at 6 months. Prognostic accuracy, as quantified by the area under the ROC curve, was significantly higher with the normalised WWM-FA value (area under the ROC curve 0·95, 95% CI 0·91-0·98) than with the standard criteria for unfavourable outcome or other MRI sequences. In a subsequent validation cohort of 50 patients (enrolled between April 1, 2015, and March 31, 2016), a normalised WWM-FA value lower than 0·91, set from the derivation cohort, had a negative predictive value of 71·4% (95% CI 41·9-91·6) and a positive predictive value of 100% (90·0-100), with 89·7% sensitivity (75·8-97·1) and 100% specificity (69·1-100) for the prediction of unfavourable outcome. INTERPRETATION: In patients who are unconscious 7 days after cardiac arrest, the normalised WWM-FA value, measured by diffusion tensor imaging, could be used to accurately predict neurological outcome at 6 months. This evidence requires confirmation from future large-scale trials with a strict protocol of withdrawal or limitation-of-care decisions and time window for MRI. FUNDING: French Ministry of Health, French National Agency for Research, Italian Ministry of Health, and Regione Lombardia.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Parada Cardíaca/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem , Adulto , Idoso , Bélgica , Encéfalo/fisiopatologia , Eletroencefalografia , Feminino , França , Parada Cardíaca/complicações , Parada Cardíaca/fisiopatologia , Humanos , Itália , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/fisiopatologia , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
5.
Stroke ; 49(3): 667-674, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29437981

RESUMO

BACKGROUND AND PURPOSE: Endovascular embolization of intracranial aneurysms with hydrogel-coated coils lowers the risk of major recurrence, but technical limitations (coil stiffness and time restriction for placement) have prevented their wider clinical use. We aimed to assess the efficacy of softer, second-generation hydrogel coils. METHODS: A randomized controlled trial was conducted at 22 centers in France and Germany. Patients aged 18 to 75 years with untreated ruptured or unruptured intracranial aneurysms measuring 4 to 12 mm in diameter were eligible and randomized (1:1 using a web-based system, stratified by rupture status) to coiling with either second-generation hydrogel coils or bare platinum coils. Assist devices were allowed as clinically required. Independent imaging core laboratory was masked to allocation. Primary end point was a composite outcome measure including major aneurysm recurrence, aneurysm retreatment, morbidity that prevented angiographic controls, and any death during treatment and follow-up. Data were analyzed as randomized. RESULTS: Randomization began on October 15, 2009, and stopped on January 31, 2014, after 513 patients (hydrogel, n=256; bare platinum, n=257); 20 patients were excluded for missing informed consent and 9 for treatment-related criteria. Four hundred eighty-four patients (hydrogel, n=243; bare platinum, n=241) were included in the analysis; 208 (43%) were treated for ruptured aneurysms. Final end point data were available for 456 patients. Forty-five out of 226 (19.9%) patients in the hydrogel group and 66/230 (28.7%) in the control group had an unfavorable composite primary outcome, giving a statistically significant reduction in the proportion of an unfavorable composite primary outcome with hydrogel coils-adjusted for rupture status-of 8.4% (95% confidence interval, 0.5-16.2; P=0.036). Adverse and serious adverse events were evenly distributed between groups. CONCLUSIONS: Our results suggest that endovascular coil embolization with second-generation hydrogel coils may reduce the rate of unfavorable outcome events in patients with small- and medium-sized intracranial aneurysms. CLINICAL TRIAL REGISTRATION: URL: https://www.drks.de/drks_web/. Unique identifier: DRKS00003132.


Assuntos
Angiografia Cerebral , Materiais Revestidos Biocompatíveis/administração & dosagem , Embolização Terapêutica , Hidrogéis/administração & dosagem , Aneurisma Intracraniano , Stents , Adolescente , Adulto , Idoso , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Masculino , Pessoa de Meia-Idade
6.
Radiology ; 287(1): 247-255, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29043908

RESUMO

Purpose To assess whether early brain functional connectivity is associated with functional recovery 1 year after cardiac arrest (CA). Materials and Methods Enrolled in this prospective multicenter cohort were 46 patients who were comatose after CA. Principal outcome was cerebral performance category at 12 months, with favorable outcome (FO) defined as cerebral performance category 1 or 2. All participants underwent multiparametric structural and functional magnetic resonance (MR) imaging less than 4 weeks after CA. Within- and between-network connectivity was measured in dorsal attention network (DAN), default-mode network (DMN), salience network (SN), and executive control network (ECN) by using seed-based analysis of resting-state functional MR imaging data. Structural changes identified with fluid-attenuated inversion recovery and diffusion-weighted imaging sequences were analyzed by using validated morphologic scales. The association between connectivity measures, structural changes, and the principal outcome was explored with multivariable modeling. Results Patients underwent MR imaging a mean 12.6 days ± 5.6 (standard deviation) after CA. At 12 months, 11 patients had an FO. Patients with FO had higher within-DMN connectivity and greater anticorrelation between SN and DMN and between SN and ECN compared with patients with unfavorable outcome, an effect that was maintained after multivariable adjustment. Anticorrelation of SN-DMN predicted outcomes with higher accuracy than fluid-attenuated inversion recovery or diffusion-weighted imaging scores (area under the receiver operating characteristic curves, respectively, 0.88, 0.74, and 0.71). Conclusion MR imaging-based measures of cerebral functional network connectivity obtained in the acute phase of CA were independently associated with FO at 1 year, warranting validation as early markers of long-term recovery potential in patients with anoxic-ischemic encephalopathy. © RSNA, 2017.


Assuntos
Encéfalo/fisiopatologia , Coma/fisiopatologia , Conectoma/métodos , Parada Cardíaca/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Vias Neurais/fisiopatologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Sobreviventes/estatística & dados numéricos
7.
Cancer Chemother Pharmacol ; 80(3): 517-526, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28707014

RESUMO

PURPOSE: This study was conducted during the development of innovative treatment targeting the microenvironment of chondrosarcoma. In this context, MMP inhibitors were conjugated with a quaternary ammonium (QA) function as a targeting ligand to proteoglycans of chondrosarcoma extracellular matrix. Here we report the proof of concept of this strategy applied to the MMP13 inhibitor, doxycycline (Dox). METHODS: A quaternary ammonium derivative of the MMP13 inhibitor doxycycline (QA-Dox) was synthesized, and its anticancer activity was evaluated in the Swarm rat chondrosarcoma (SRC) model compared with the parent drug doxycycline, in vitro and in vivo. In vivo, dox and QA-Dox efficiency was assessed at equimolar doses according to a q4dx4 schedule by monitoring tumour volume by MRI and PG-targeted scintigraphy. Molecular mechanism (MMP13 expression, proteoglycan level) and histology studies were performed on tumours. RESULTS: The link of QA targeting function to Dox maintained the MMP13 inhibitory activity in vitro. Interestingly, the bacteriostatic activity was lost. SRC cells incubated with both drugs were blocked in S and G2 M phases. Tumour growth inhibition (confirmed by histology) was observed for both Dox and QA-Dox. Undesirable blood effects (leukocyte decrease) were reduced when Dox was targeted to tumour tissue using the QA function. CONCLUSIONS: In the SRC model, the MMP13 inhibitor Dox and its QA derivative are promising as adjuvant therapies for chondrosarcoma management.


Assuntos
Compostos de Amônio/uso terapêutico , Condrossarcoma/tratamento farmacológico , Doxiciclina/uso terapêutico , Compostos de Amônio/administração & dosagem , Compostos de Amônio/farmacologia , Condrossarcoma/patologia , Doxiciclina/administração & dosagem , Doxiciclina/farmacologia , Humanos
8.
Neuroscience ; 349: 291-302, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28245989

RESUMO

Detection of awareness in patients with consciousness disorders is a challenge that can be facilitated by functional neuroimaging. We elaborated a functional magnetic resonance imaging (fMRI) protocol to detect covert activity in altered states of consciousness. We hypothesized that passive listening to narratives with graduated emotional charge triggers graduated cerebral activations. The fMRI protocol was designed in healthy subjects for further clinical applications. The emotional charge was graduated using voice familiarity and long-term declarative memory content: low emotional charge, unknown person telling general semantic memory; mean emotional charge, relative telling the same narratives; high emotional charge, same relative telling autobiographical memory. Autobiographical memory was subdivided into semantic autobiographical memory and episodic autobiographical memory. The protocol proved efficient at triggering graduated cerebral activations: low emotional charge, superior temporal gyri and sulci; mean emotional charge, same as low emotional charge plus bilateral premotor cortices and left inferior frontal gyrus; high emotional charge, cingulate, temporal, frontal, prefrontal and angular areas, thalamus and cerebellum. Semantic autobiographical memory revealed larger activations than episodic autobiographical memory. Independent ROI analysis confirmed the preponderant contribution of narratives with autobiographical memory content in triggering cerebral activation, not only in autobiographical memory-sensitive areas, but also in voice-sensitive, language-sensitive and semantic memory-sensitive areas.


Assuntos
Mapeamento Encefálico , Emoções/fisiologia , Adolescente , Adulto , Percepção Auditiva , Feminino , Neuroimagem Funcional/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Memória Episódica , Rememoração Mental/fisiologia , Adulto Jovem
9.
Crit Care Med ; 45(8): e763-e771, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28272153

RESUMO

OBJECTIVES: We hypothesize that the combined use of MRI cortical thickness measurement and subcortical gray matter volumetry could provide an early and accurate in vivo assessment of the structural impact of cardiac arrest and therefore could be used for long-term neuroprognostication in this setting. DESIGN: Prospective cohort study. SETTING: Five Intensive Critical Care Units affiliated to the University in Toulouse (France), Paris (France), Clermont-Ferrand (France), Liège (Belgium), and Monza (Italy). PATIENTS: High-resolution anatomical T1-weighted images were acquired in 126 anoxic coma patients ("learning" sample) 16 ± 8 days after cardiac arrest and 70 matched controls. An additional sample of 18 anoxic coma patients, recruited in Toulouse, was used to test predictive model generalization ("test" sample). All patients were followed up 1 year after cardiac arrest. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cortical thickness was computed on the whole cortical ribbon, and deep gray matter volumetry was performed after automatic segmentation. Brain morphometric data were employed to create multivariate predictive models using learning machine techniques. Patients displayed significantly extensive cortical and subcortical brain volumes atrophy compared with controls. The accuracy of a predictive classifier, encompassing cortical and subcortical components, has a significant discriminative power (learning area under the curve = 0.87; test area under the curve = 0.96). The anatomical regions which volume changes were significantly related to patient's outcome were frontal cortex, posterior cingulate cortex, thalamus, putamen, pallidum, caudate, hippocampus, and brain stem. CONCLUSIONS: These findings are consistent with the hypothesis of pathologic disruption of a striatopallidal-thalamo-cortical mesocircuit induced by cardiac arrest and pave the way for the use of combined brain quantitative morphometry in this setting.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Parada Cardíaca/patologia , Adulto , Córtex Cerebelar/diagnóstico por imagem , Córtex Cerebelar/patologia , Coma/diagnóstico por imagem , Coma/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
10.
Magn Reson Med ; 78(4): 1296-1305, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27851869

RESUMO

PURPOSE: Changes in glutamate (Glu) levels occur in a number of neurodegenerative diseases. We proposed the use of 13 C spectroscopy and the highly amplified signal generated by hyperpolarization to achieve spatial and temporal resolutions adequate for in vivo studies of Glu metabolism in the healthy rat brain. Thus, we investigated uptake of hyperpolarized [1-13C ]Glu after a temporary blood-brain barrier (BBB) disruption protocol and its conversion to glutamine (Gln) in the brain. METHODS: [1-13 C]Glu was hyperpolarized using the dynamic nuclear polarization process. A temporary BBB disruption using mannitol allowed hyperpolarized [1-13 C]Glu to reach the brain. Then, hyperpolarized [1-13 C]Glu brain metabolism was observed in vivo by MR spectroscopy experiments at 3T. Products synthesized from [1-13 C]Glu were assigned via liquid chromatography-mass spectrometry. RESULTS: Hyperpolarized [1-13 C]Glu reached 20% ± 2.3% polarization after 90 min. After validation of the BBB disruption protocol, hyperpolarized [1-13 C]Glu (175.4 ppm) was detected inside the rat brain, and the formation of [1-13 C]Gln at 174.9 ppm was also observed. CONCLUSION: The Gln synthesis from hyperpolarized [1-13 C]Glu can be monitored in vivo in the healthy rat brain after opening the BBB. Magn Reson Med 78:1296-1305, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Assuntos
Encéfalo/metabolismo , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Isótopos de Carbono/metabolismo , Glucose/metabolismo , Ácido Glutâmico/análise , Ácido Glutâmico/química , Glutamina/análise , Glutamina/química , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos , Ratos Sprague-Dawley
11.
Neuroradiology ; 58(8): 777-86, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27137926

RESUMO

INTRODUCTION: Hybrid hydrogel-platinum coils (HydroCoil) have proven effective for endovascular aneurysm treatment. To overcome technical limitations (coil stiffness, time restriction for placement), a second generation of softer hydrogel coils has been brought to clinical practice (HydroSoft, HydroFrame). We report on procedural safety and core-lab-assessed angiographic results from an open-label multicenter randomized controlled trial. METHODS: Web-based randomization occurred in 15 medical centers in France and seven in Germany between coil embolization with second-generation hydrogel coils and treatment with any bare platinum coil. Assist devices could be used as clinically required. Primary endpoint is a composite outcome including major aneurysm recurrence and poor clinical outcome at 18 months follow-up. RESULTS: Five hundred thirteen patients were randomized (hydrogel n = 256, bare platinum n = 257). Twenty patients were excluded for missing informed consent and nine patients for treatment related criteria. Four hundred eighty-four patients were analyzed as randomized (hydrogel n = 243, bare platinum n = 241). Two hundred eight had ruptured aneurysms (43 %). Prespecified procedural complications occurred in 58 subjects (hydrogel n = 28, bare platinum n = 30, p = 0.77). The 14-day mortality rate was 2.1 % in both arms of the study. The median calculated packing densities for aneurysms assigned to hydrogel and bare platinum were 39 and 31 % respectively (p < 0.001). No statistically significant differences were found between arms in the post procedural angiographic occlusion rate (p = 0.8). CONCLUSION: Second-generation hydrogel coils can be used in a wide spectrum of aneurysms with a risk profile equivalent to bare platinum. Packing density was significantly higher in aneurysms treated with hydrogel coils. TRIAL REGISTRATION: http://www.germanctr.de , DRKS00003132.


Assuntos
Prótese Vascular , Procedimentos Endovasculares/instrumentação , Hidrogéis/química , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Platina/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral/métodos , Análise de Falha de Equipamento , Feminino , França , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Resultado do Tratamento
12.
PLoS One ; 11(3): e0152614, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27029050

RESUMO

Despite a better understanding of brain language organization into large-scale cortical networks, the underlying white matter (WM) connectivity is still not mastered. Here we combined diffusion tensor imaging (DTI) fiber tracking (FT) and language functional magnetic resonance imaging (fMRI) in twenty healthy subjects to gain new insights into the macroscopic structural connectivity of language. Eight putative WM fascicles for language were probed using a deterministic DTI-FT technique: the arcuate fascicle (AF), superior longitudinal fascicle (SLF), uncinate fascicle (UF), temporo-occipital fascicle, inferior fronto-occipital fascicle (IFOF), middle longitudinal fascicle (MdLF), frontal aslant fascicle and operculopremotor fascicle. Specific measurements (i.e. volume, length, fractional anisotropy) and precise cortical terminations were derived for each WM fascicle within both hemispheres. Connections between these WM fascicles and fMRI activations were studied to determine which WM fascicles are related to language. WM fascicle volumes showed asymmetries: leftward for the AF, temporoparietal segment of SLF and UF, and rightward for the frontoparietal segment of the SLF. The lateralization of the AF, IFOF and MdLF extended to differences in patterns of anatomical connections, which may relate to specific hemispheric abilities. The leftward asymmetry of the AF was correlated to the leftward asymmetry of fMRI activations, suggesting that the lateralization of the AF is a structural substrate of hemispheric language dominance. We found consistent connections between fMRI activations and terminations of the eight WM fascicles, providing a detailed description of the language connectome. WM fascicle terminations were also observed beyond fMRI-confirmed language areas and reached numerous cortical areas involved in different functional brain networks. These findings suggest that the reported WM fascicles are not exclusively involved in language and might be related to other cognitive functions such as visual recognition, spatial attention, executive functions, memory, and processing of emotional and behavioral aspects.


Assuntos
Córtex Cerebral , Conectoma , Imagem de Tensor de Difusão , Idioma , Imageamento por Ressonância Magnética , Substância Branca , Adulto , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiologia , Feminino , Humanos , Masculino , Radiografia , Substância Branca/diagnóstico por imagem , Substância Branca/fisiologia
13.
Eur Radiol ; 26(7): 2352-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26427699

RESUMO

PURPOSE: To evaluate the safety and clinical effectiveness of percutaneous vertebroplasty (PVP) in patients aged 80 and over. METHODS: One hundred and seventy-three patients (127 women, 46 men; mean age = 84.2y) underwent 201 PVP procedures (391 vertebrae) in our institution from June 2008 to March 2012. One hundred and twenty-six patients (73 %) had osteoporotic vertebral compression fractures (VCF), 36 (20.5 %) were treated for tumour lesions, and the remaining 11 (6.5 %) for lesions from another cause. Comorbidities and American Society of Anesthesiologists (ASA) scores were assessed before treatment. Periprocedural and delayed complications were systematically recorded. A qualitative scale was used to evaluate pain relief at 1-month follow-up, ranging from significant pain worsening to marked improvement or disappearance. New fracture occurrence was assessed on follow-up imaging. RESULTS: Forty-five percent of patients had pretreatment ASA class scores ≥3. No major complication occurred. Pain was unchanged in 16.9 % of cases, mildly improved in 31.5 %, and disappeared in 47.8 %. We identified 27 (11 %) symptomatic new VCFs in patients with osteoporosis on follow-up imaging. The mean delay in diagnosis of new fractures was 5 ± 8.7 months. CONCLUSIONS: Even in the elderly, PVP remains a safe and effective technique for pain relief, independently of the underlying disease. KEY POINTS: • Post-PVP pain improvement was observed in 79.3 % of elderly patients. • PVP remains a safe technique in elderly patients. • No decompensation of comorbidity was observed in our series.


Assuntos
Fraturas por Compressão/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vertebroplastia/métodos , Idoso de 80 Anos ou mais , Feminino , Fraturas por Compressão/complicações , Humanos , Masculino , Dor/etiologia , Fraturas da Coluna Vertebral/complicações , Resultado do Tratamento
14.
Radiology ; 278(2): 505-13, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26237591

RESUMO

PURPOSE: To assess the neurochemical profile in the putamen of patients with parkinsonian syndromes undergoing L-3,4-dihydroxyphenylalanine (L-DOPA) treatment (drug-on) or after withdrawal of L-DOPA medication (drug-off) compared with healthy volunteers to identify dopaminergic therapy-sensitive biomarkers of Parkinson disease. MATERIALS AND METHODS: The local institutional review board approved the study, and all participants gave informed consent. A short echo-time (29 msec) single-voxel (1-cm(3)) proton (hydrogen 1 [(1)H]) magnetic resonance (MR) spectroscopic approach was used at 3 T to explore the metabolic profile in the putamen of patients with Parkinson disease. Spectra obtained from 20 healthy volunteers were blindly compared with spectra obtained from 20 patients with parkinsonian syndromes in drug-on and drug-off conditions in a randomized permuted block study to assess the accuracy of diagnostic biomarkers for Parkinson disease and efficacy of L-DOPA therapy. The statistical tests were two sided, with a type-I error set at α of .05. Random-effects models were used to compare healthy subjects and patients with parkinsonian syndromes in drug-on or drug-off conditions. RESULTS: Measured concentrations of putaminal total N-acetylaspartate (tNAA) (8.1 ± 0.2 vs 9.4 ± 0.4; P < .01), total creatine (tCr) (7.5 ± 0.2 vs 8.3 ± 0.3; P < .01), and myo-inositol (m-Ins) (3.8 ± 0.3 vs 5.6 ± 0.4; P < .001) were significantly lower in patients with parkinsonian syndromes in drug-off condition than in healthy volunteers. Moreover, L-DOPA therapy restored tNAA (9.1 ± 0.4 vs 8.1 ± 0.2; P < .01) and tCr (8.1 ± 0.3 vs 7.5 ± 0.2; P < .01) levels, whereas m-Ins levels remained unchanged. The combined glutamate and glutamine and choline showed no changes in drug-off or drug-on condition compared with those in control subjects. CONCLUSION: tNAA, tCr, and m-Ins were identified as putative biomarkers of Parkinson disease in the putamen of patients. tNAA and tCr levels are responsive to L-DOPA therapy.


Assuntos
Antiparkinsonianos/uso terapêutico , Espectroscopia de Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico , Doença de Parkinson/tratamento farmacológico , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prótons , Reprodutibilidade dos Testes , Resultado do Tratamento
15.
PLoS One ; 10(11): e0141358, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550990

RESUMO

For different functional magnetic resonance imaging experiments using blood oxygenation level-dependent (BOLD) contrast, the acquisition of T2*-weighted scans at a high spatial resolution may be advantageous in terms of time-course signal-to-noise ratio and of BOLD sensitivity when the regions are prone to susceptibility artifacts. In this study, we explore this solution by examining how spatial resolution influences activations elicited when appetizing food pictures are viewed. Twenty subjects were imaged at 3 T with two different voxel volumes, 3.4 µl and 27 µl. Despite the diminution of brain coverage, we found that high-resolution acquisition led to a better detection of activations. Though known to suffer to different degrees from susceptibility artifacts, the activations detected by high spatial resolution were notably consistent with those reported in published activation likelihood estimation meta-analyses, corresponding to taste-responsive regions. Furthermore, these regions were found activated bilaterally, in contrast with previous findings. Both the reduction of partial volume effect, which improves BOLD contrast, and the mitigation of susceptibility artifact, which boosts the signal to noise ratio in certain regions, explained the better detection noted with high resolution. The present study provides further evidences that high spatial resolution is a valuable solution for human BOLD fMRI, especially for studying food-related stimuli.


Assuntos
Mapeamento Encefálico/métodos , Neuroimagem Funcional/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Campos Magnéticos , Masculino , Oxigênio/sangue , Razão Sinal-Ruído
16.
Drug Des Devel Ther ; 9: 3853-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26229445

RESUMO

BACKGROUND: Paracetamol's (APAP) mechanism of action suggests the implication of supraspinal structures but no neuroimaging study has been performed in humans. METHODS AND RESULTS: This randomized, double-blind, crossover, placebo-controlled trial in 17 healthy volunteers (NCT01562704) aimed to evaluate how APAP modulates pain-evoked functional magnetic resonance imaging signals. We used behavioral measures and functional magnetic resonance imaging to investigate the response to experimental thermal stimuli with APAP or placebo administration. Region-of-interest analysis revealed that activity in response to noxious stimulation diminished with APAP compared to placebo in prefrontal cortices, insula, thalami, anterior cingulate cortex, and periaqueductal gray matter. CONCLUSION: These findings suggest an inhibitory effect of APAP on spinothalamic tracts leading to a decreased activation of higher structures, and a top-down influence on descending inhibition. Further binding and connectivity studies are needed to evaluate how APAP modulates pain, especially in the context of repeated administration to patients with pain.


Assuntos
Acetaminofen/farmacologia , Analgésicos não Narcóticos/farmacologia , Encéfalo/efeitos dos fármacos , Dor/tratamento farmacológico , Adulto , Encéfalo/metabolismo , Estudos Cross-Over , Método Duplo-Cego , Potenciais Evocados/efeitos dos fármacos , Humanos , Imageamento por Ressonância Magnética , Masculino , Tratos Espinotalâmicos/efeitos dos fármacos , Tratos Espinotalâmicos/metabolismo , Adulto Jovem
17.
J Neuroradiol ; 42(6): 326-31, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26026192

RESUMO

OBJECTIVES: The aim of this work was to compare the performance of a prototype radioprotection cabin in interventional neuroradiology, and to assess its suitability for routine use. MATERIALS AND METHODS: The radioprotection cabin was a prototype derived from the CATHPAX AF(®) model. Three operators carried out 21 procedures (19 brain arteriographies and 2 embolizations) using the radioprotection cabin and not wearing the usual lead individual protection equipment (IPE), and 17 procedures (16 brain arteriographies and 1 embolization) wearing the standard lead IPE (vest, skirt, thyroid shield and goggles), and not using the radioprotection cabin. In all cases, thermoluminescent dosimeters (TLDs) were positioned at head, trunk, pelvic region, and upper and lower limbs to measure the dose equivalent for Hp(0.07) or Hp(3) that they received, attenuated by either the cabin or the lead IPE. Parallel to these dosimetric measurements, the ergonomics of the protection cabin were appraised by each radiologist after each procedure. RESULTS AND CONCLUSION: The cabin procured an overall reduction of 74% of the dose received on the whole body with Hp(0.07)=0.04 mSv ± 0.01 (CL=95%) against Hp(0.07)=0.12 mSv ± 0.04 (CL=95%) for the IPE. Body protection with the cabin was near complete, and close to 100% for the regions not protected by the usual IPE (e.g. the head). We also showed that design weaknesses noted by the operators that hampered procedures (light reflections, reduced hand mobility, awkward access to radioscopy pedal) could be remedied by maker's improvements to the prototype and minor changes in work habits.


Assuntos
Teste de Materiais , Exposição Ocupacional/prevenção & controle , Doses de Radiação , Proteção Radiológica/métodos , Desenho de Equipamento , Ergonomia , Humanos , Dosimetria Termoluminescente
18.
Neuroradiology ; 57(6): 599-604, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25724881

RESUMO

The effectiveness of a hybrid hydrogel platinum detachable coil (HydroCoil; MicroVention Inc., Tustin, CA) for endovascular aneurysm treatment has been proven in a recently published RCT. Due to technical restrictions (coil stiffness, time restriction for placement), the HydroSoft coil as well as a corresponding 3D framing coil, the HydroFrame coil (MicroVention Inc., Tustin, CA), a class of new softer coils containing less hydrogel and swelling more slowly than the HydroCoil, have been developed and brought to clinical practice. The present study aims to compare the effectiveness of endovascular aneurysm treatment with coil embolization between patients allocated HydroSoft/HydroFrame versus bare platinum coiling. GREAT is a randomized, controlled, multicentre trial in patients bearing cerebral aneurysms to be treated by coil embolization. Eligible patients were randomized to either coil embolization with HydroSoft/HydroFrame coils (>50 % of administered coil length), or bare platinum coils. Inclusion criteria were as follows: age 18-75, ruptured aneurysm (WFNS 1-3) and unruptured aneurysm with a diameter between 4 and 12 mm. Anatomy such that endovascular coil occlusion deemed possible and willingness of the neurointerventionalist to use either HydroSoft/HydroFrame or bare platinum coils. Exclusion criteria were as follows: aneurysms previously treated by coiling or clipping. Primary endpoint is a composite of major aneurysm recurrence on follow-up angiography and poor clinical outcome (modified Rankin scale 3 or higher), both assessed at 18 months post treatment. Risk differences for poor outcomes will be estimated in a modified intention-to-treat analysis stratified by rupture status (DRKS-ID: DRKS00003132).


Assuntos
Embolização Terapêutica/instrumentação , Procedimentos Endovasculares , Aneurisma Intracraniano/terapia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa , Adulto Jovem
19.
J Neuroradiol ; 42(4): 229-35, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25451669

RESUMO

OBJECTIVE: Central retinal artery occlusion (CRAO) is a rare disease with poor visual prognosis. We evaluated clinical effectiveness of in situ fibrinolysis with original angiographic scores describing the aspect of carotid siphon, proximal ophthalmic artery, and choroid blush. METHODS: Retrospective study of 16 consecutive cases of CRAO between 2007 and 2013. Fourteen underwent in situ fibrinolysis, two were excluded due to pre-occlusive internal carotid stenosis on pre-procedural diagnostic angio-CT. Fibrinolysis was performed with rt-PA (average injected dose: 35 mg), with an average onset delay of 8hours (4-17h). We reported angiographic scores pre- and post-fibrinolysis, visual acuity (VA) before and after treatment, and VA improvement evaluated by ophthalmologist 6 to 12 months after thrombolysis. RESULTS: Six patients (43%) recovered post-fibrinolysis VA significally improved, superior or equal to 1/10 (1/10 to 8/10). An irregular carotid siphon (2 cases) appeared as a predictive factor of failure. Fibrinolysis procedure led to a significant improvement of angiographic permeability of proximal ophthalmic artery (P=0.0498), but this result was not accompanied by any VA improvement. The aspect of choroid blush showed no correlation with the management of thrombolysis. CONCLUSION: In situ fibrinolysis was more effective than medical treatments or natural evolution of CRAO (VA improvement was respectively 40% and 20%). However, the benefit/risk ratio must be discussed, and an angio-CT of supra-aortic trunks could be systematically performed before thrombolysis, to assess the potential VA recovery compared with complications such as ischemic stroke.


Assuntos
Fibrinolíticos/administração & dosagem , Radiografia Intervencionista/métodos , Oclusão da Artéria Retiniana/diagnóstico por imagem , Oclusão da Artéria Retiniana/tratamento farmacológico , Terapia Trombolítica/métodos , Ativador de Plasminogênio Tecidual/administração & dosagem , Adulto , Idoso , Feminino , Humanos , Injeções Intra-Arteriais , Injeções Intraoculares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terapia Trombolítica/instrumentação , Resultado do Tratamento , Adulto Jovem
20.
J Neurointerv Surg ; 6(4): 286-90, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23709581

RESUMO

BACKGROUND: Coiling of ruptured intracranial aneurysms in elderly patients remains debatable in terms of technical feasibility and clinical outcome. AIMS: In this observational cohort study we aimed to assess the technical feasibility, complication profile and clinical outcomes of elderly patients with subarachnoid hemorrhage (SAH) treated with endovascular therapy. METHODS: The study included 59 consecutive patients (47 women) aged ≥70 years (mean age 76 years, range 71-84) admitted to our institution with SAH from January 2002 to July 2011. The patients were treated for 66 aneurysms (regular coiling: n=62 (94%), balloon-assisted technique: n=2 (3%), stent and coil technique: n=2 (3%)). World Federation of Neurosurgery (WFNS) grade at admission was 1 in 13 patients, 2 in 23 patients, 3 in 8 patients, 4 in 11 patients and 5 in 4 patients. We analysed data by univariate and multivariate statistical analyses with an emphasis on the initial clinical situation, complications and clinical outcome. RESULTS: The technical success rate was 98% with a procedure-related deficit rate of 10% and procedure-related death rate of 5%. The Glasgow Outcome Scale score at 6 months was 1 in 15 patients (25.4%), 2 in 8 patients (13.6%), 3 in 14 patients (23.7%), 4 in 11 patients (18.6%) and 5 in 11 patients (18.6%). Patients admitted with a high initial WFNS grade did not differ statistically in terms of clinical outcome. The final clinical outcome was not significantly correlated with age, initial Fisher score or procedure-related complications. CONCLUSIONS: Endovascular treatment of elderly patients with ruptured cerebral aneurysms is feasible, safe and beneficial regardless of the presenting WFNS score.


Assuntos
Aneurisma Intracraniano/terapia , Índice de Gravidade de Doença , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/métodos , Estudos de Coortes , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Masculino , Stents , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/terapia , Resultado do Tratamento
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