RESUMO
BACKGROUND: Fatigue is common in multiple sclerosis and is associated with reduced quality of life. This study aimed to assess the correlation between fatigue scores and data from other self-assessment questionnaires, neuropsychological tests and neuroimaging, as well as data on neuroimmunological markers in cerebrospinal fluid (CSF) and serum/plasma, in clinically isolated syndrome (CIS) and relapsing remitting MS (RRMS). METHODS: Modified fatigue impact scale (MFIS) scores were determined in 38 patients with newly diagnosed CIS or RRMS at baseline and after one year in a prospective longitudinal cohort study. Non-parametric correlation analyses were used to assess associations between MFIS scores and other self-assessment questionnaire data (Hospital Anxiety and Depression scale (HAD), Multiple Sclerosis Impact Scale 29 (MSIS-29) and Short Form 36 (SF-36)), as well as with neuropsychological test performances (e.g. Auditory Consonant Trigram Test (ACTT)), clinical parameters (e.g. disease duration and expanded disability status scale (EDSS)), magnetic resonance imaging (MRI) data (number of T2 lesions in brain MRI and total brain volume) and several neurodegenerative/neuroinflammatory markers in CSF and serum/plasma (IL-1ß, IL-6, CXCL1, CXCL10, CXCL13, CCL-22 in plasma; neurofilament light chain (NFL) in serum; IL-6, CXCL1, CXCL10, CXCL13, CCL22, NFL and chitinase-3-like-1 (CHI3L1) in CSF. CSF and serum/plasma from 21 age- and sex-matched healthy controls were available for comparison. RESULTS: At both baseline and one-year follow-up, fatigue scores correlated significantly with HAD, MSIS-29 and SF-36 scores and ACTT performance (Spearman´s rho 0.45-0.78, all pâ¯≤â¯0.01) but not with the other neuropsychological test results, disease duration, EDSS ratings, number of T2 lesions, total brain volume or neurodegenerative/neuroinflammatory markers, including neurofilament light chain levels in CSF and serum. In group comparisons, MFIS scores were similar in patients fulfilling no evidence of disease activity-3 (NEDA-3) (nâ¯=â¯18) and patients not fulfilling NEDA-3 (nâ¯=â¯20) during one year of follow-up (p > 0.01). CONCLUSIONS: In this cohort of patients with newly diagnosed CIS and RRMS, fatigue scores were associated with mood, disease impact on daily life and quality of life as well as with alterations of attentive functions. Study results indicate that subjective fatigue scores are not well reflected by some commonly used and objectively measurable disease parameters like EDSS, T2 lesions and NFL levels.
Assuntos
Doenças Desmielinizantes , Autoavaliação Diagnóstica , Fadiga , Esclerose Múltipla Recidivante-Remitente , Proteínas de Neurofilamentos/metabolismo , Receptores Nicotínicos/sangue , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/diagnóstico por imagem , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/fisiopatologia , Fadiga/etiologia , Fadiga/metabolismo , Fadiga/fisiopatologia , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/metabolismo , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Proteínas de Neurofilamentos/sangue , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Índice de Gravidade de DoençaRESUMO
BACKGROUND AND PURPOSE: As a high proportion of people with clinically isolated syndrome (pwCIS) exhibit sympathetic adrenergic and sudomotor dysfunction, the aim of this study was to investigate the evolution of autonomic nervous system (ANS) abnormalities in pwCIS over a 2-year follow-up. METHODS: This was a prospective cohort study in which 121 pwCIS were enrolled and followed for 2 years. After 2-year follow-up, data were available for 84 pwCIS. ANS symptoms were evaluated with the Composite Autonomic System Score-31 (COMPASS-31) and results of the ANS tests were expressed using the Composite Autonomic Scoring Scale (CASS) at baseline and visit at month 24. Symptomatic dysautonomia was defined if the patient had a COMPASS-31 value above the median of the whole cohort at baseline evaluation (COMPASS-31 > 6.79) and CASS score >0. RESULTS: Complete CASS data at baseline and month 24 were available for 62 patients; in 24 (38.7%) patients there was worsening, in 16 (25.8%) there was improvement and in 22 (35.5%) there was no change in CASS score. In 90% of pwCIS (72 of 80) there was no change in parasympathetic nervous system tests, whereas 47.3% (35 of 74) had either worsening or improvement in sympathetic adrenergic and 28.6% (20 of 70) had either worsening or improvement in sudomotor function. A multivariable regression model identified the total number of T2 lesions as an independent predictor for worsening of symptomatic dysautonomia. No predictors for worsening or improving of CASS score were identified. CONCLUSION: A substantial proportion of pwCIS experienced worsening of ANS abnormalities during the 2-year follow-up and magnetic resonance imaging parameters seemed to predict these abnormalities.
Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Sistema Nervoso Autônomo/fisiopatologia , Doenças Desmielinizantes/fisiopatologia , Esclerose Múltipla/fisiopatologia , Adulto , Sistema Nervoso Autônomo/diagnóstico por imagem , Doenças do Sistema Nervoso Autônomo/diagnóstico por imagem , Doenças do Sistema Nervoso Autônomo/etiologia , Estudos de Coortes , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/diagnóstico por imagem , Progressão da Doença , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Sistema Nervoso Parassimpático/fisiopatologia , Estudos Prospectivos , Sistema Nervoso Simpático/fisiopatologiaRESUMO
Simultaneous performance of motor and cognitive tasks may compete for common brain network resources in aging or patients with some neurological diseases, suggesting the occurrence of a cognitive-motor interference. While this phenomenon has been well described for multiple sclerosis (MS) patients, it never has been tested on asymptomatic subject with magnetic resonance imaging (MRI) findings suggestive of demyelinating disease (i.e., radiologically isolated syndrome: RIS). In this pilot study, 10 RIS subjects and 10 sex/age-matched healthy controls were tested by means of static posturography under eyes opened (single-task trial) and while performing two different cognitive tasks (semantic modified word list generation for first dual-task trial and phonemic semantic modified word list generation for second dual-task trial), to estimate the dual-task cost (DTC) of standing balance. In our sample, under cognitive interference (without any substantial differences between semantic and phonemic modified word list generation), the RIS group showed significance differences in CoP (center of pressure) total sway area, ellipse eccentricity, CoP sway path length, CoP median sway velocity along the AP (anteroposterior) axis and along the ML (mediolateral) axis, reflecting a higher negative DTC respect to healthy subjects (which have simply shown a statistical trend, failing to reach a significance, in some trials). The phenomenon of cognitive-motor interference might be unmasked by a dual-task posturography in RIS subjects, too. We hypothesize that this approach could be useful to early reveal the presence of a demyelinating disease and to reach a MS diagnosis in subjects otherwise classified as RIS.
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Cognição , Doenças Desmielinizantes/diagnóstico , Imageamento por Ressonância Magnética , Equilíbrio Postural , Adulto , Encéfalo/diagnóstico por imagem , Doenças Desmielinizantes/fisiopatologia , Doenças Desmielinizantes/psicologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Projetos Piloto , Radiografia , Medula Espinal/diagnóstico por imagem , Adulto JovemRESUMO
INTRODUCTION: The perception of colour is one of the visual functions affected by optic neuritis. Most of the tests currently available for evaluating dichromatism are based on assessing the hue, but no clinical studies have been conducted to investigate the formation of afterimages on the retina of these patients. AIMS: To evaluate the dichromatism acquired in demyelinating optic neuritis by means of the formation of afterimages on the retina. SUBJECTS AND METHODS: This is an observation-based, cross-sectional, case-control study. The cases are patients with at least one bout of optic neuritis and confirmed multiple sclerosis. A healthy age- and sex-paired control was selected for each case. The main variable is the capacity to see afterimages after saturation of the retinal photoreceptor cells. A specific computer application was developed to evaluate this phenomenon. RESULTS: The sample consisted of 30 cases and 30 controls (63% females; mean age: 33 years; range: 18-48 years). The cases showed less probability of seeing the afterimage (36.6% of the cases, while none of the controls failed to see an afterimage) and, if it was seen, it remained for less time. The ROC curve shows a sensitivity of 86.3% and a specificity of 83.3%. The odds ratio was 5 (95% confidence interval: 2.21-11.3) for the probability of seeing the afterimage in controls versus cases. CONCLUSIONS: Patients with at least one episode of optic neuritis presented a lower capacity to observe afterimages. The test is therefore useful in the assessment and follow-up of functional damage in demyelinating optic neuropathies.
TITLE: Valoracion de la formacion de postimagenes mediante una nueva aplicacion informatica en pacientes con neuropatias opticas desmielinizantes.Introduccion. En las neuritis opticas se afecta, entre otras funciones visuales, la percepcion del color. La mayoria de las pruebas existentes para evaluar discromatopsias se basa en evaluar el matiz, pero no se ha estudiado clinicamente la formacion de postimagenes en la retina en estos pacientes. Objetivo. Evaluar la discromatopsia adquirida en las neuritis opticas desmielinizantes mediante la formacion de postimagenes en la retina. Sujetos y metodos. Estudio observacional, transversal, de casos y controles. Los casos son pacientes con al menos un episodio de neuritis optica y esclerosis multiple confirmada. Se selecciono un control sano por cada caso, emparejado por edad y sexo. La variable principal es la capacidad de ver postimagenes tras saturar los fotorreceptores retinianos. Para evaluar dicho fenomeno se desarrollo una aplicacion informatica especifica. Resultados. La muestra comprende 30 casos y 30 controles (63% mujeres; edad media: 33 años; rango: 18-48 años). Los casos mostraron menor probabilidad de ver la postimagen (el 36,6% de los casos y ningun control no veian postimagen) y, en caso de verla, una menor permanencia de ella. La curva ROC muestra una sensibilidad del 86,3% y una especificidad del 83,3%. La odds ratio era de 5 (intervalo de confianza al 95%: 2,21-11,3) para la probabilidad de ver la postimagen en los controles frente a los casos. Conclusiones. Los pacientes con al menos un episodio de neuritis optica presentan una menor capacidad de observar postimagenes, por lo que la prueba es util para la evaluacion y el seguimiento del daño funcional en neuropatias opticas desmielinizantes.
Assuntos
Pós-Imagem , Doenças Desmielinizantes/fisiopatologia , Esclerose Múltipla/fisiopatologia , Neurite Óptica/fisiopatologia , Adolescente , Adulto , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/fisiopatologia , Adulto JovemRESUMO
OBJECTIVE: The aim of this observational study was to evaluate the applicability of a recently introduced ultrasound score (Bochum ultrasound score; BUS) in distinguishing the chronic inflammatory demyelinating polyneuropathy (CIDP) from the multifocal motor neuropathy (MMN) or the multifocal acquired demyelinating sensory and motor neuropathy (MADSAM). METHODS: The BUS underwent prospective evaluation of its applicability in a group of 13 patients (mean age 47.2, SD ± 13.7, 9 women), who were referred to our department between January 2012 and August 2013 with the clinical picture of a chronic symmetrical or asymmetrical sensory/sensorimotor neuropathy. RESULTS: The cut-off value of ≥ 2 points in the "Bochum ultrasound score" showed a sensitivity of 80% and specificity of 87.5% (PPV=80%, NPV=87.5%) in distinguishing CIDP from MMN or MADSAM. CONCLUSIONS: The BUS seems to allow a reliable distinction of CIDP from multifocal acquired demyelinating polyneuropathies causing predominantly motor nerve dysfunction, such as MMN or MADSAM. Our ultrasound findings indicate a stronger relationship of MADSAM to MMN, than to CIDP.
Assuntos
Doenças Desmielinizantes/diagnóstico por imagem , Indicadores Básicos de Saúde , Condução Nervosa/fisiologia , Polineuropatias/diagnóstico por imagem , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Nervos Espinhais/diagnóstico por imagem , Adulto , Doenças Desmielinizantes/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurônios Motores , Polineuropatias/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Nervo Radial/diagnóstico por imagem , Nervo Radial/fisiopatologia , Sensibilidade e Especificidade , Nervos Espinhais/fisiopatologia , Nervo Sural/diagnóstico por imagem , Nervo Sural/fisiopatologia , Nervo Ulnar/diagnóstico por imagem , Nervo Ulnar/fisiopatologia , UltrassonografiaRESUMO
OBJECTIVE: To evaluate multifocal visual evoked potentials (mfVEP) changes in optic neuritis (ON) and fellow eyes during first year after the attack. METHODS: Eighty-seven patients and twenty-five controls were examined. Patients were classified as multiple sclerosis (MS) group, high risk (HR) or low risk (LR) groups for conversion to MS. mfVEP recordings and retinal nerve fiber layer (RNFL) thickness were analyzed. RESULTS: Recovery of amplitude and shortening of latency was fastest within the first 3months. The largest amplitude reduction and longest latency delay of the ON eye were recorded in the MS group. This was accompanied by deterioration of both parameters in fellow eyes (p<0.03). mfVEP remained stable in fellow eyes of the LR group. Inter-eye asymmetry showed similar amount of amplitude reduction and latency delay in all three groups. RNFL thickness strongly correlated with mfVEP amplitude as early as 3 months after ON (R(2)=0.6, p=0.001). CONCLUSION: mfVEP amplitude is an early predictor of post-ON axonal loss. The apparent more severe involvement of ON eyes in the MS subgroup may be due to subclinical inflammation along the visual pathway. SIGNIFICANCE: Severity of amplitude reduction and latency delay after episode of ON is not MS-related. Retro-chiasmal demyelination is a possible factor contributing to amplitude and latency differences between MS and non-MS patients.
Assuntos
Potenciais Evocados Visuais/fisiologia , Neurite Óptica/diagnóstico , Vias Visuais/fisiopatologia , Percepção Visual/fisiologia , Adulto , Axônios/fisiologia , Doenças Desmielinizantes/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurite Óptica/fisiopatologia , Adulto JovemRESUMO
The potential of diffusion tensor imaging (DTI) indices and volumes of focal lesions on conventional magnetic resonance imaging to predict conversion to multiple sclerosis (MS) was analyzed in subjects with clinically isolated syndrome (CIS) over 4 years. Twenty patients with CIS and 10 healthy controls were included in the study. The data showed an association between the volumes of T1 and fluid-attenuated inversion recovery (FLAIR) lesions and conversion to MS (T1: P=.02; FLAIR: P=.02). The worsening of DTI indices (mean diffusivity and fractional anisotropy) was primarily seen in patients progressing to MS, but clear-cut association with conversion could not be detected.
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Encéfalo/patologia , Doenças Desmielinizantes/diagnóstico , Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico , Substância Branca/patologia , Adulto , Anisotropia , Encéfalo/fisiopatologia , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Substância Branca/fisiopatologia , Adulto JovemRESUMO
INTRODUCTION: A simple test to evaluate the peripheral C-fiber function is the measurement of axon reflex flare area. In this study, we compared the flare area in healthy subjects and in two groups of patients with predominantly axonal or demyelinating polyneuropathy. MATERIALS AND METHODS: We examined 42 control subjects and 33 patients. The flare responses were elicited by the application of transcutaneous electrical stimulation and recorded by laser Doppler imaging. RESULTS: There was a significant reduction of electrically induced flare area in both groups of neuropathy patients (P < 0.001; analysis of covariance). Interestingly, patients with an axonal neuropathy had a significantly stronger reduction of flare size as compared to patients with demyelinating neuropathy (P = 0.03). CONCLUSIONS: The evaluation of the axon flare response in the arm can be used as a screening test of impaired C-fiber function in polyneuropathy patients with the advantages of simplicity of the procedure and time economy.
Assuntos
Axônios/diagnóstico por imagem , Doenças Desmielinizantes/fisiopatologia , Eletrodiagnóstico/métodos , Fibras Nervosas Amielínicas/diagnóstico por imagem , Polineuropatias/fisiopatologia , Reflexo/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estimulação Elétrica/instrumentação , Estimulação Elétrica/métodos , Eletrodiagnóstico/instrumentação , Feminino , Antebraço/fisiopatologia , Humanos , Lasers , Masculino , Pessoa de Meia-Idade , Medição da Dor , Limiar da Dor/fisiologia , Ultrassonografia Doppler , Adulto JovemRESUMO
BACKGROUND: A clinically isolated syndrome (CIS) is the first manifestation of multiple sclerosis (MS). Previous task-related functional MRI studies demonstrate functional reorganization in patients with CIS. PURPOSE: To assess baseline brain activity changes in patients with CIS by using the technique of regional amplitude of low frequency fluctuation (ALFF) as an index in resting-state fMRI. MATERIAL AND METHODS: Resting-state fMRIs data acquired from 37 patients with CIS and 37 age- and sex-matched normal controls were compared to investigate ALFF differences. The relationships between ALFF in regions with significant group differences and the EDSS (Expanded Disability Status Scale), disease duration, and T2 lesion volume (T2LV) were further explored. RESULTS: Patients with CIS had significantly decreased ALFF in the right anterior cingulate cortex, right caudate, right lingual gyrus, and right cuneus (P < 0.05 corrected for multiple comparisons using Monte Carlo simulation) compared to normal controls, while no significantly increased ALFF were observed in CIS. No significant correlation was found between the EDSS, disease duration, T2LV, and ALFF in regions with significant group differences. CONCLUSION: In patients with CIS, resting-state fMRI demonstrates decreased activity in several brain regions. These results are in contrast to patients with established MS, in whom ALFF demonstrates several regions of increased activity. It is possible that this shift from decreased activity in CIS to increased activity in MS could reflect the dynamics of cortical reorganization.
Assuntos
Doenças Desmielinizantes/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Mapeamento Encefálico/métodos , Estudos de Casos e Controles , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Estudos ProspectivosRESUMO
BACKGROUND: There is evidence that at least 5% of Multiple sclerosis (MS) cases manifest in childhood. Children with MS present with a demyelinating episode involving single or multiple symptoms prior to developing a second event (usually within two years) to then meet criteria for diagnosis. There is evidence from adult cohorts that the incidence and sex ratios of MS are changing and that children of immigrants have a higher risk for developing MS. A paediatric population should reflect the vanguard of such changes and may reflect trends yet to be observed in adult cohorts. Studying a paediatric population from the first demyelinating event will allow us to test these hypotheses, and may offer further valuable insights into the genetic and environmental interactions in the pathogenesis of MS. METHODS/DESIGN: The Paediatric UK Demyelinating Disease Longitudinal Study (PUDDLS) is a prospective longitudinal observational study which aims to determine the natural history, predictors and outcomes of childhood CNS inflammatory demyelinating diseases. PUDDLS will involve centres in the UK, and will establish a cohort of children affected with a first CNS inflammatory demyelinating event for long-term follow up by recruiting for approximately 5 years. PUDDLS will also establish a biological sample archive (CSF, serum, and DNA), allowing future hypothesis driven research. For example, the future discovery of a biomarker will allow validation within this dataset for the evaluation of novel biomarkers. Patients will also be requested to consent to be contacted in the future. A secondary aim is to collaborate internationally with the International Paediatric Multiple Sclerosis Study Group when future collaborative studies are proposed, whilst sharing a minimal anonymised dataset. PUDDLS is the second of two jointly funded studies. The first (UCID-SS) is an epidemiological surveillance study that already received ethical approvals, and started on the 1st September 2009. There is no direct patient involvement, and UCID-SS aims to determine the UK and Ireland incidence of CNS inflammatory demyelinating disorders in children under 16 years. DISCUSSION: A paediatric population should reflect the vanguard of MS epidemiological changes and may reflect trends yet to be observed in adult MS cohorts. The restricted window between clinical expression of disease and exposure to environmental factors in children offers a unique research opportunity. Studying a paediatric population from the first demyelinating event will allow us to investigate the changing epidemiology of MS, and may offer further valuable insights into the genetic and environmental interactions in the pathogenesis of MS.
Assuntos
Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/fisiopatologia , Esclerose Múltipla/fisiopatologia , Biomarcadores/análise , Criança , Efeitos Psicossociais da Doença , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/tratamento farmacológico , Diagnóstico Diferencial , Progressão da Doença , Diagnóstico Precoce , Humanos , Estudos Longitudinais , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/etiologia , Estudos Prospectivos , Qualidade de Vida , Reino Unido/epidemiologiaRESUMO
OBJECTIVE: In this multicenter study, a new semiautomatic method for segmenting the cervical cord from C2 to C5 was used to investigate the correlation between cord atrophy and clinical disability in a large sample of patients with multiple sclerosis (MS). METHODS: T2 and 3-dimensional T1-weighted cervical cord scans and dual-echo brain scans were acquired from 143 healthy controls, 22 patients with clinically isolated syndromes (CIS), 101 patients with relapsing-remitting MS (RRMS), 79 patients with secondary progressive MS (SPMS), 58 patients with benign MS (BMS), and 75 patients with primary progressive MS (PPMS) in 3 European centers. Normalized cervical cord cross-sectional area (CSAn) was measured by an active surface cord model. Between-group comparisons were performed using linear mixed-effect models. A nonparametric kernel estimator was used to obtain smoothed plots of CSA along the cervical cord. RESULTS: Cord CSAn was significantly lower in PPMS vs healthy controls, BMS vs RRMS, SPMS vs BMS, and RRMS. From C2 to C5, a net separation and definition of the plots of patients with BMS, PPMS, and SPMS was seen with respect to those of the other study groups. CSAn was correlated with Expanded Disability Status Scale (r = -0.49, p < 0.0001), with a differential effect among disease clinical phenotypes: no association in either CIS or in BMS; association in RRMS (r = -0.30, p = 0.001), SPMS (r = -0.34, p = 0.001), and PPMS (r = -0.27, p = 0.01). CONCLUSIONS: Cervical cord atrophy provides a relevant and useful marker for the characterization of clinical heterogeneity of patients with MS. The stability of this measure among different centers supports its use as potential outcome measure to monitor disease progression in multicenter trials.
Assuntos
Vértebras Cervicais , Progressão da Doença , Esclerose Múltipla/patologia , Fenótipo , Medula Espinal/patologia , Adulto , Idoso , Doenças Desmielinizantes/patologia , Doenças Desmielinizantes/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/fisiopatologia , Adulto JovemRESUMO
The electrophysiological findings in optic nerve and primary ganglion cell dysfunction are reviewed. The value of the pattern reversal visual-evoked potential (VEP) in the diagnosis of optic nerve disease, and the pattern appearance VEP in the demonstration of the intracranial misrouting associated with albinism, are discussed. The pattern electroretinogram (PERG) is used in the direct assessment of ganglion cell function. The use of PERG or multifocal electroretinography (mfERG), to enable the distinction between VEP delay due to optic nerve disease and that due to macular dysfunction, is described.
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Doenças do Nervo Óptico/fisiopatologia , Albinismo/fisiopatologia , Doenças Desmielinizantes/fisiopatologia , Eletrorretinografia/métodos , Potenciais Evocados Visuais/fisiologia , Humanos , Macula Lutea/fisiopatologia , Síndromes de Compressão Nervosa/fisiopatologia , Neuropatia Óptica Isquêmica/fisiopatologia , Células Ganglionares da Retina/fisiologiaRESUMO
Identifying the role of axonal injury in the development of permanent, irreversible neurologic disability is important to the study of central nervous system (CNS) demyelinating diseases. Our understanding of neurologic dysfunction in demyelinating diseases and the ability to assess therapeutic interventions depends on the development of objective functional assays that can non-invasively measure axonal loss. In this study, we demonstrate in a murine model of progressive CNS demyelination that assessment of the hindlimb width of stride provides a powerful indicator of axonal loss and can dissociate between deficits induced by demyelination versus axonal loss.
Assuntos
Axônios/patologia , Sistema Nervoso Central/patologia , Doenças Desmielinizantes/patologia , Coxeadura Animal/patologia , Degeneração Neural/patologia , Fibras Nervosas Mielinizadas/patologia , Animais , Axônios/ultraestrutura , Axônios/virologia , Biomarcadores , Infecções por Cardiovirus/patologia , Infecções por Cardiovirus/fisiopatologia , Sistema Nervoso Central/ultraestrutura , Sistema Nervoso Central/virologia , Doenças Desmielinizantes/fisiopatologia , Doenças Desmielinizantes/virologia , Modelos Animais de Doenças , Feminino , Coxeadura Animal/fisiopatologia , Coxeadura Animal/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Degeneração Neural/fisiopatologia , Degeneração Neural/virologia , Fibras Nervosas Mielinizadas/ultraestrutura , Fibras Nervosas Mielinizadas/virologia , Theilovirus/fisiologiaRESUMO
PURPOSE: To study, by neurophysiological means, the possible involvement of the retina, in demyelinating optic neuritis (DON). MATERIAL AND METHODS: Thirty-five patients fulfilling strict criteria of unilateral DON were investigated with a battery of neurophysiological tests and MRI within 3 weeks of the onset of their symptoms. Flash-ERG (F-ERG) in photopic conditions, Flash-VEPs and PR-VEPs were recorded. MRI of the brain and the optic nerve were performed. RESULTS: The amplitude of b-wave of F-ERG in photopic conditions was statistically significantly lower in the affected eye (p < 0.001) compared to normal controls, whereas in the unaffected eye, it was also statistically significantly lower than normal controls (p < 0.01). All patients had statistically significant prolongation of P100 latency in PR-VEPs of the affected eye (p < 0.001) in comparison to normal controls. The P100 wave of the unaffected eye was also delayed (p < 0.01). In MRI, Gd-DTPA enhancement was observed in 7 symptomatic nerves with only minimal enhancement of the optic nerve between optic chiasm and optic canal, whereas 11 patients were presented with intracranial associated plaques. Five of the above patients had optic nerve enhancement and diffused demyelinating findings simultaneously. CONCLUSION: These results are a neurophysiological indication of involvement of the retina in DON, probably of vascular origin.
Assuntos
Doenças Desmielinizantes/diagnóstico , Eletrorretinografia , Potenciais Evocados Visuais/fisiologia , Neurite Óptica/diagnóstico , Adulto , Doenças Desmielinizantes/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nervo Óptico/patologia , Nervo Óptico/fisiopatologia , Neurite Óptica/fisiopatologia , Tempo de Reação/fisiologia , Valores de ReferênciaRESUMO
A 60-year-old man presented with progressive large fiber sensory loss in the right first three fingers and, to a lesser extent, in both fourth and fifth fingers. Electrophysiologic studies were characteristic of chronic sensory demyelinating polyneuropathy, a variant of chronic inflammatory demyelinating polyneuropathy. Plasma exchange was unsuccessful, but intravenous immunoglobulin (IVIG) led to complete recovery of sensation for 2 months, although neurophysiologic abnormalities persisted. A battery of noninvasive tests to measure hand grip strength, tactile sensation at the fingertips, and motor control of prehension during precision grip revealed marked abnormalities in the right hand before IVIG. One month after IVIG, all test results had normalized, but they returned to pretreatment levels after 3 months. Functional evaluation of the hand may be a sensitive method to objectively quantify loss of and changes in cutaneous mechanoreceptor function of the fingers in large fiber sensory neuropathy.
Assuntos
Doenças Desmielinizantes/fisiopatologia , Mãos/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Análise e Desempenho de Tarefas , Fatores de TempoRESUMO
Relatively pain-free excitation of both superficial and deep nerves in the assessment of nerve conduction velocity is the main advantage of magnetic stimulation over conventional electrical stimulation. General utility of this technique has often been called into question by a number of authors because of difficulties in obtaining supramaximal responses or in determining the exact site of impulse generation when stimulating a peripheral nerve distally. Meanwhile, magnetic stimulation of the cervical and lumbar roots has become a routine procedure for the assessment of peripheral conduction time and is combined with transcranial magnetic stimulation of the motor cortex in the assessment of central conduction time. Recent developments in magnetic coil and stimulator design have improved the focality of the stimulus, so that selective supramaximal stimuli can be delivered to commonly studied peripheral nerves in the upper and lower limbs, both at proximal and distal segments. Furthermore, the introduction of small figure-8-shaped coils enables safe diagnosis of chronic compression syndromes with exact assessment of conduction velocities over short distances of peripheral nerves. The ease of application of magnetic stimulation and the absence of pain for the patient make magnetic stimulation a particularly attractive method for also investigating patients with demyelinating polyneuropathies, and will certainly replace conventional electrical stimulation in the near future.
Assuntos
Magnetismo , Doenças do Sistema Nervoso Periférico/diagnóstico , Doenças Desmielinizantes/fisiopatologia , Estimulação Elétrica , Humanos , Doenças do Sistema Nervoso Periférico/fisiopatologia , PolirradiculoneuropatiaRESUMO
Pregnant Dorset horn gimmers inoculated with a non-cytopathic strain of the border disease virus produced "hairy shaker" lambs that were individually affected to a varying degree. Surviving lambs were observed for a period of up to 20 weeks when neurological signs were seen to gradually disappear. During this time live virus was isolated from a wide variety of sites in nearly all of the infected lambs. The infected animals grew at a significantly slower rate compared with the controls, particularly during the first 15 weeks. Several morphological defects are described the most consistent being the decreased weight of the central nervous system. By 20 weeks body-weights were about 20 per cent lower and carcase quality scores were reduced. An assessment is made of the economic losses attributable to BD taking into consideration carcase quality at 20 weeks and the perinatal losses.