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PURPOSE: To establish the extent of agreement for ISCEV standard reference pattern reversal VEPs (prVEPs) acquired at three European centres, to determine any effect of sex, and to establish reference intervals from birth to adolescence. METHODS: PrVEPs were recorded from healthy reference infants and children, aged 2 weeks to 16 years, from three centres using closely matched but non-identical protocols. Amplitudes and peak times were modelled with orthogonal quadratic and sigmoidal curves, respectively, and two-sided limits, 2.5th and 97.5th centiles, estimated using nonlinear quantile Bayesian regression. Data were compared by centre and by sex using median quantile confidence intervals. The 'critical age', i.e. age at which P100 peak time ceased to shorten, was calculated. RESULTS: Data from the three centres were adequately comparable. Sex differences were not clinically meaningful. The pooled data showed rapid drops in P100 peak time which stabilised by 27 and by 34 weeks for large and small check widths, respectively. Post-critical-age reference limits were 87-115 ms and 96-131 ms for large and small check widths, respectively. Amplitudes varied markedly and reference limits for all ages were 5-57 µV and 3.5-56 µV for large and small check widths, respectively. CONCLUSIONS: PrVEP reference data could be combined despite some methodology differences within the tolerances of the ISCEV VEP Standard, supporting the clinical benefit of ISCEV Standards. Comparison with historical data is hampered by lack of minimum reporting guidelines. The reference data presented here could be validated or transformed for use elsewhere.
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Eletrorretinografia , Potenciais Evocados Visuais , Lactente , Adolescente , Humanos , Criança , Masculino , Feminino , Voluntários Saudáveis , Teorema de BayesRESUMO
This document developed by the International Society for Clinical Electrophysiology of Vision (ISCEV) provides guidance for calibration and verification of stimulus and recording systems specific to clinical electrophysiology of vision. This guideline provides additional information for those using ISCEV Standards and Extended protocols and supersedes earlier Guidelines. The ISCEV guidelines for calibration and verification of stimuli and recording instruments (2023 update) were approved by the ISCEV Board of Directors 01, March 2023.
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Eletrorretinografia , Visão Ocular , Eletrorretinografia/métodos , CalibragemRESUMO
A guideline is proposed that comprises the minimum items to be reported in research studies involving an eye tracker and human or non-human primate participant(s). This guideline was developed over a 3-year period using a consensus-based process via an open invitation to the international eye tracking community. This guideline will be reviewed at maximum intervals of 4 years.
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The full-field electroretinogram (ERG) is a mass electrophysiological response to diffuse flashes of light and is used widely to assess generalized retinal function. This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV), presents an updated and revised ISCEV Standard for clinical ERG testing. Minimum protocols for basic ERG stimuli, recording methods and reporting are specified, to promote consistency of methods for diagnosis, monitoring and inter-laboratory comparisons, while also responding to evolving clinical practices and technology. The main changes in this updated ISCEV Standard for clinical ERGs include specifying that ERGs may meet the Standard without mydriasis, providing stimuli adequately compensate for non-dilated pupils. There is more detail about analysis of dark-adapted oscillatory potentials (OPs) and the document format has been updated and supplementary content reduced. There is a more detailed review of the origins of the major ERG components. Several tests previously tabulated as additional ERG protocols are now cited as published ISCEV extended protocols. A non-standard abbreviated ERG protocol is described, for use when patient age, compliance or other circumstances preclude ISCEV Standard ERG testing.
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Eletrorretinografia , Sociedades Médicas , Eletrorretinografia/métodos , Humanos , Estimulação Luminosa/métodos , Retina , Visão OcularRESUMO
INTRODUCTION: Establishing robust reference intervals for clinical procedures has received much attention from international clinical laboratories, with approved guidelines. Physiological measurement laboratories have given this topic less attention; however, most of the principles are transferable. METHODS: Herein, we summarise those principles and expand them to cover bilateral measurements and one-tailed reference intervals, which are common issues for those interpreting clinical visual electrophysiology tests such as electroretinograms (ERGs), visual evoked potentials (VEPs) and electrooculograms (EOGs). RESULTS: The gold standard process of establishing and defining reference intervals, which are adequately reliable, entails collecting data from a minimum of 120 suitable reference individuals for each partition (e.g. sex, age) and defining limits with nonparametric methods. Parametric techniques may be used under some conditions. A brief outline of methods for defining reference limits from patient data (indirect sampling) is given. Reference intervals established elsewhere, or with older protocols, can be transferred or verified with as few as 40 and 20 suitable reference individuals, respectively. Consideration is given to small numbers of reference subjects, interpretation of serial measurements using subject-based reference values, multidimensional reference regions and age-dependent reference values. Bilateral measurements, despite their correlation, can be used to improve reference intervals although additional care is required in computing the confidence in the reference interval or the reference interval itself when bilateral measurements are only available from some of subjects. DISCUSSION: Good quality reference limits minimise false-positive and false-negative results, thereby maximising the clinical utility and patient benefit. Quality indicators include using appropriately sized reference datasets with appropriate numerical handling for reporting; using subject-based reference limits where appropriate; and limiting tests for each patient to only those which are clinically indicated, independent and highly discriminating.
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Eletrorretinografia , Potenciais Evocados Visuais , Eletroculografia , Humanos , Valores de Referência , Visão OcularRESUMO
PURPOSE: Visual evoked potentials (VEPs) can be used to measure visual resolution via a spatial frequency (SF) limit as an objective estimate of visual acuity. The aim of this systematic review is to collate descriptions of the VEP SF limit in humans, healthy and disordered, and to assess how accurately and precisely VEP SF limits reflect visual acuity. METHODS: The protocol methodology followed the PRISMA statement. Multiple databases were searched using "VEP" and "acuity" and associated terms, plus hand search: titles, abstracts or full text were reviewed for eligibility. Data extracted included VEP SF limits, stimulus protocols, VEP recording and analysis techniques and correspondence with behavioural acuity for normally sighted healthy adults, typically developing infants and children, healthy adults with artificially degraded vision and patients with ophthalmic or neurological conditions. RESULTS: A total of 155 studies are included. Commonly used stimulus, recording and analysis techniques are summarised. Average healthy adult VEP SF limits vary from 15 to 40 cpd, depend on stimulus, recording and analysis techniques and are often, but not always, poorer than behavioural acuity measured either psychophysically with an identical stimulus or with a clinical acuity test. The difference between VEP SF limit and behavioural acuity is variable and strongly dependent on the VEP stimulus and choice of acuity test. VEP SF limits mature rapidly, from 1.5 to 9 cpd by the end of the first month of life to 12-20 cpd by 8-12 months, with slower improvement to 20-40 cpd by 3-5 years. VEP SF limits are much better than behavioural thresholds in the youngest, typically developing infants. This difference lessens with age and reaches equivalence between 1 and 2 years; from around 3-5 years, behavioural acuity is better than the VEP SF limit, as for adults. Healthy, artificially blurred adults had slightly better behavioural acuity than VEP SF limits across a wide range of acuities, while adults with heterogeneous ophthalmic or neurological pathologies causing reduced acuity showed a much wider and less consistent relationship. For refractive error, ocular media opacity or pathology primarily affecting the retina, VEP SF limits and behavioural acuity had a fairly consistent relationship across a wide range of acuity. This relationship was much less consistent or close for primarily macular, optic nerve or neurological conditions such as amblyopia. VEP SF limits were almost always normal in patients with non-organic visual acuity loss. CONCLUSIONS: The VEP SF limit has great utility as an objective acuity estimator, especially in pre-verbal children or patients of any age with motor or learning impairments which prevent reliable measurement of behavioural acuity. Its diagnostic power depends heavily on adequate, age-stratified, reference data, age-stratified empirical calibration with behavioural acuity, and interpretation in the light of other electrophysiological and clinical findings. Future developments could encompass faster, more objective and robust techniques such as real-time, adaptive control. REGISTRATION: International prospective register of systematic reviews PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ ), registration number CRD42018085666.
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Ambliopia , Potenciais Evocados Visuais , Adulto , Criança , Pré-Escolar , Eletrorretinografia , Humanos , Lactente , Visão Ocular , Acuidade VisualRESUMO
The International Society for Clinical Electrophysiology of Vision (ISCEV) standard for visual evoked potentials (VEPs) describes a minimum procedure for clinical VEP testing and encourages more extensive testing. This ISCEV extended protocol is an extension to the VEP standard. It describes procedures for recording multiple VEPs to a range of sizes of pattern stimuli to establish the VEP spatial frequency limit (threshold) and for relating this limit to visual acuity.
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Eletrorretinografia , Potenciais Evocados Visuais , Sociedades Médicas , Visão Ocular , Acuidade VisualRESUMO
AIM: To systematically review and meta-analyse studies of neurodevelopmental outcome of children born to mothers prescribed methadone in pregnancy. METHOD: MEDLINE, Embase, and PsycINFO were searched for studies published from 1975 to 2017 reporting neurodevelopmental outcomes in children with prenatal methadone exposure. RESULTS: Forty-one studies were identified (2283 participants). Eight studies were amenable to meta-analysis: at 2 years the Mental Development Index weighted mean difference of children with prenatal methadone exposure compared with unexposed infants was -4.3 (95% confidence interval [CI] -7.24 to -1.63), and the Psychomotor Development Index weighted mean difference was -5.42 (95% CI -10.55 to -0.28). Seven studies reported behavioural scores and six found scores to be lower among methadone-exposed children. Twelve studies reported visual outcomes: nystagmus and strabismus were common; five studies reported visual evoked potentials of which four described abnormalities. Factors that limited the quality of some studies, and introduced risk of bias, included absence of blinding, small sample size, high attrition, uncertainty about polydrug exposure, and lack of comparison group validity. INTERPRETATION: Children born to mothers prescribed methadone in pregnancy are at risk of neurodevelopmental problems but risk of bias limits inference about harm. Research into management of opioid use disorder in pregnancy should include evaluation of childhood neurodevelopmental outcome. WHAT THIS PAPER ADDS: Children born to opioid-dependent mothers prescribed methadone are at risk of neurodevelopmental impairment. Exposed infants have lower Mental Development Index and Psychomotor Development Index scores than unexposed children. Atypical visual evoked potentials, strabismus, and nystagmus have increased prevalence. Estimates of impairment may be biased by intermediate to poor quality evidence.
DESARROLLO NEUROLÓGICO INFANTIL TRAS LA PRESCRIPCIÓN DE METADONA DE MANTENIMIENTO PARA EL TRATAMIENTO DE LA DEPENDENCIA DE OPIOIDES DURANTE EL EMBARAZO: REVISIÓN SISTEMÁTICA Y META-ANÁLISIS: OBJETIVO: Revisar sistemáticamente y realizar un meta-análisis de estudios sobre el resultado del desarrollo neurológico de los niños nacidos de madres a quienes se les recetó metadona durante el embarazo. METODOLOGÍA: Se realizó una búsqueda en MEDLINE, Embase, y PsycINFO de estudios publicados desde el año 1975 al 2017 que informaran sobre el resultado del desarrollo neurológico de niños que hubieran tenido exposición prenatal a la metadona. RESULTADOS: Se identificaron 41 estudios (2283 participantes). Ocho estudios se pudieron someter al meta-análisis: a los dos años de edad los niños con exposición prenatal a la metadona mostraron una diferencia de medias ponderada de -4,3 (95% intervalo de confianza [IC] −7,24 to −1,63) en el Índice de Desarrollo Mental (Mental Development Index) en comparación con los niños no expuestos. En el Índice de Desarrollo Psicomotor (Psychomotor Development Index) la diferencia de medias ponderada fue −5,42 (95% CI −10,55 to −0,28). 7 estudios mostraron las puntuaciones comportamentales y 6 de ellos encontraron puntuaciones más bajas entre los niños expuestos a la metadona. Doce estudios informaron sobre los resultados a nivel visual: el nistagmo y el estrabismo fueron comunes; 5 estudios informaron sobre los potenciales evocados visuales, de los cuáles cuatro describieron anormalidades. Los factores que limitaron la calidad de algunos estudios e introdujeron el riesgo de sesgo, incluyeron la ausencia de cegamiento, el pequeño tamaño de la muestra, el alto desgaste, la incertidumbre acerca de la exposición a varias drogas y la falta de validez del grupo de comparación. INTERPRETACIÓN: Los niños nacidos de madres a quienes se les recetó metadona durante el embarazo se encuentran en riesgo de sufrir problemas de desarrollo neurológico, pero el riesgo de sesgo limita la inferencia sobre el daño. La investigación sobre el manejo del trastorno por uso de opioides en el embarazo debe incluir la evaluación del resultado del desarrollo neurológico infantil.
NEURODESENVOLVIMENTO INFANTIL APÓS PRESCRIÇÃO DE METADONA DE MANUTENÇÃO PARA DEPENDÊNCIA DE OPIÓIDES NA GESTAÇÃO: UMA REVISÃO SISTEMÁTICA E METANÁLISE: OBJETIVO: Revisar sistematicamente e metanalisar os estudos com resultados do neurodesenvolvimento de crianças nascidas de mães que tiveram prescrição de metadona na gestação. MÉTODO: MEDLINE, Embase, e PsycINFO foram pesquisadas por estudos publicados de 1974 a 2017 relatando resultados do neurodesenvolvimento em crianças expostas a metadona no período pré-natal. RESULTADOS: Quarenta e um estudos foram identificados (2.283 participantes). Oito estudos foram possíveis de incluir na metanálise: aos 2 anos a diferença na média ponderada do Índice de Desenvolvimento Mental de crianças expostas a metadona pré-natal comparadas com as não expostas foi −4,3 (intervalo de confiança [IC a 95%] −7,24 a −1,63), e a diferença na média ponderada do Índice de Desenvolvimento Psicomotor foi −5,42 (IC 95% −10,55 a −0,28). Sete estudos relataram escores comportamentais e seis encontraram escores menores entre crianças expostas a metadona. Doze estudos relataram resultados visuais: nistagmo e estrabismo foram comuns; cinco estudos reportaram potenciais evocados visuais, dos quais quatro descreveram anormalidades. Fatores que limitaram a qualidade de alguns estudos e introduziram risco de viéis incluíram falta de cegamento, reduzido tamanho amostral, desgaste alto, incerteza sobre exposição a outras drogas, e falta de validade por grupo de comparação. INTERPRETAÇÃO: Crianças nascidas de mães que receberam prescrição de metadona na gestação apresentam risco para problemas neurodesenvolvimentais, mas o risco de viés limita as inferências sobre o dano. Pesquisas sobre o manejo do uso de opióides na gestação devem incluir a avaliação do resultado do neurodesenvolvimento na infância.
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Desenvolvimento Infantil , Metadona/uso terapêutico , Entorpecentes/uso terapêutico , Transtornos Relacionados ao Uso de Opioides/complicações , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Complicações na Gravidez/tratamento farmacológico , Criança , Desenvolvimento Infantil/efeitos dos fármacos , Pré-Escolar , Feminino , Humanos , Lactente , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologia , Efeitos Tardios da Exposição Pré-NatalRESUMO
The International Society for Clinical Electrophysiology of Vision (ISCEV) standard for full-field electroretinography (ERG) describes a minimum protocol for clinical testing but encourages additional ERG testing when appropriate. This ISCEV extended protocol describes methods to record and evaluate a light-adapted (LA) ERG stimulus-response series with increasing flash strengths. The LA ERG stimulus-response series (also referred to as the luminance-response or intensity-response series in the published literature) can characterise generalised cone system function more comprehensively than the ISCEV standard LA ERGs alone. The amplitude of LA ERG a-waves, arising from cones and cone off-bipolar cells, typically shows a saturating function. The LA ERG b-wave amplitudes, which arise primarily from activity of retinal bipolar cells, show an amplitude peak followed by a nonzero plateau (the "photopic hill" phenomenon). This ISCEV extended protocol specifies a stimulus-response series suitable to evaluate generalised dysfunction affecting the LA retina, to aid in distinguishing between the on- and off-responses of the cone system and to monitor ERG changes in these characteristics. The LA ERG stimulus-response series for a- and b-waves is recorded to a sequence of nine flash stimuli ranging from 0.03 to 300 cd s m-2, superimposed on a standard background of 30 cd m-2. A shorter protocol is also presented to measure the mid-range of the function (the "photopic hill") using 5 flash stimuli.
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Protocolos Clínicos/normas , Eletrorretinografia/métodos , Oftalmopatias Hereditárias/fisiopatologia , Doenças Genéticas Ligadas ao Cromossomo X/fisiopatologia , Luz , Miopia/fisiopatologia , Cegueira Noturna/fisiopatologia , Estimulação Luminosa/métodos , Retina/fisiopatologia , Adulto , Humanos , Oftalmologia/organização & administração , Células Fotorreceptoras Retinianas Cones/fisiologia , Sociedades Médicas/organização & administraçãoRESUMO
The International Society for Clinical Electrophysiology of Vision (ISCEV) standard for full-field electroretinography (ERG) describes a minimum procedure, but encourages more extensive testing. This ISCEV extended protocol describes an extension to the ERG standard, namely the dark-adapted (DA) red flash ERG. The DA red flash ERG can be incorporated conveniently within the ISCEV standard ERG protocol after a minimum of 20-min DA and recorded after the DA 0.01 ERG to a flash strength of 0.3 phot cd s m-2, eliciting a waveform with two positive peaks in healthy individuals. The first positive component is the cone-mediated x-wave with a peak at 30-50 ms; the second is a rod-mediated b-wave with a peak time of approximately 100 ms. Shorter DA times may be desirable to shorten the recording time or to alter the prominence of the early cone-mediated x-wave relative to the rod-mediated b-wave. The DA red flash ERG is used to aid the diagnosis of achromatopsia (rod monochromacy), cone dystrophy and other forms of cone system dysfunction, including "Bradyopsia" (RGS9/R9AP-retinopathy), when the DA red flash ERG x-wave is preserved in the absence of ISCEV standard LA ERGs. The DA red flash ERG can also help determine the origin of residual DA ERGs in cases of severe rod dysfunction, for example in disorders such as vitamin A deficiency, fundus albipunctatus (RDH5-retinopathy), Oguchi disease (SAG- or GRK1-retinopathy) and some rod-cone dystrophies. To shorter DA periods, the x-wave may be elicited without the following rod b-wave, shown to be helpful in abbreviated protocols for children.
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Adaptação à Escuridão/fisiologia , Eletrofisiologia/normas , Eletrorretinografia/métodos , Estimulação Luminosa , Células Fotorreceptoras Retinianas Cones/fisiologia , Distrofias Retinianas/fisiopatologia , Adulto , Criança , Protocolos Clínicos/normas , Feminino , Humanos , Masculino , Sociedades Médicas/organização & administração , Deficiência de Vitamina ARESUMO
This document, from the International Society for Clinical Electrophysiology of Vision (ISCEV), presents an updated and revised ISCEV Standard for full-field clinical electroretinography (ffERG or simply ERG). The parameters for Standard flash stimuli have been revised to accommodate a variety of light sources including gas discharge lamps and light emitting diodes. This ISCEV Standard for clinical ERGs specifies six responses based on the adaptation state of the eye and the flash strength: (1) Dark-adapted 0.01 ERG (rod ERG); (2) Dark-adapted 3 ERG (combined rod-cone standard flash ERG); (3) Dark-adapted 3 oscillatory potentials; (4) Dark-adapted 10 ERG (strong flash ERG); (5) Light-adapted 3 ERG (standard flash "cone" ERG); and (6) Light-adapted 30 Hz flicker ERG. ISCEV encourages the use of additional ERG protocols for testing beyond this minimum standard for clinical ERGs.
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Eletrorretinografia/normas , Oftalmologia/organização & administração , Células Fotorreceptoras de Vertebrados/fisiologia , Sociedades Médicas/normas , Acomodação Ocular/fisiologia , Adaptação à Escuridão/fisiologia , Eletrodos , Eletrorretinografia/instrumentação , Humanos , Estimulação Luminosa/métodos , Neurônios Retinianos/fisiologiaRESUMO
Purpose: This feasibility study investigated the practicability of collecting and analyzing tear proteins from preterm infants at risk of retinopathy of prematurity (ROP). We sought to identify any tear proteins which might be implicated in the pathophysiology of ROP as well as prognostic markers. Methods: Schirmer's test was used to obtain tear samples from premature babies, scheduled for ROP screening, after parental informed consent. Mass spectrometry was used for proteomic analysis. Results: Samples were collected from 12 infants, which were all adequate for protein analysis. Gestational age ranged from 25 + 6 to 31 + 1 weeks. Postnatal age at sampling ranged from 19 to 66 days. One infant developed self-limiting ROP. Seven hundred one proteins were identified; 261 proteins identified in the majority of tear samples, including several common tear proteins, were used for analyses. Increased risk of ROP as determined by the postnatal growth ROP (G-ROP) criteria was associated with an increase in lactate dehydrogenase B chain in tears. Older infants demonstrated increased concentration of immunoglobulin complexes within their tear samples and two sets of twins in the cohort showed exceptionally similar proteomes, supporting validity of the analysis. Conclusions: Tear sampling by Schirmer test strips and subsequent proteomic analysis by mass spectrometry in preterm infants is feasible. A larger study is required to investigate the potential use of tear proteomics in identification of ROP. Translational Relevance: Tear sampling and subsequent mass spectrometry in preterm infants is feasible. Investigation of the premature tear proteome may increase our understanding of retinal development and provide noninvasive biomarkers for identification of treatment-warranted ROP.
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Biomarcadores , Proteínas do Olho , Estudos de Viabilidade , Idade Gestacional , Recém-Nascido Prematuro , Proteômica , Retinopatia da Prematuridade , Lágrimas , Humanos , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/metabolismo , Proteômica/métodos , Recém-Nascido , Feminino , Lágrimas/química , Lágrimas/metabolismo , Masculino , Biomarcadores/metabolismo , Biomarcadores/análise , Proteínas do Olho/metabolismo , Proteínas do Olho/análise , Lactente , Espectrometria de Massas/métodosRESUMO
The innate immune system is the primary defence against the versatile pathogen, Staphylococcus aureus. How this organism is able to avoid immune killing and cause infections is poorly understood. Using an established larval zebrafish infection model, we have shown that overwhelming infection is due to subversion of phagocytes by staphylococci, allowing bacteria to evade killing and found foci of disease. Larval zebrafish coinfected with two S. aureus strains carrying different fluorescent reporter gene fusions (but otherwise isogenic) had bacterial lesions, at the time of host death, containing predominantly one strain. Quantitative data using two marked strains revealed that the strain ratios, during overwhelming infection, were often skewed towards the extremes, with one strain predominating. Infection with passaged bacterial clones revealed the phenomenon not to bedue to adventitious mutations acquired by the pathogen. After infection of the host, all bacteria are internalized by phagocytes and the skewing of population ratios is absolutely dependent on the presence of phagocytes. Mathematical modelling of pathogen population dynamics revealed the data patterns are consistent with the hypothesis that a small number of infected phagocytes serve as an intracellular reservoir for S. aureus, which upon release leads to disseminated infection. Strategies to specifically alter neutrophil/macrophage numbers were used to map the potential subpopulation of phagocytes acting as a pathogen reservoir, revealing neutrophils as the likely 'niche'. Subsequently in a murine sepsis model, S. aureus abscesses in kidneys were also found to be predominantly clonal, therefore likely founded by an individual cell, suggesting a potential mechanism analogous to the zebrafish model with few protected niches. These findings add credence to the argument that S. aureus control regimes should recognize both the intracellular as well as extracellular facets of the S. aureus life cycle.
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Evasão da Resposta Imune , Fagócitos/imunologia , Fagócitos/microbiologia , Staphylococcus aureus/patogenicidade , Peixe-Zebra/microbiologia , Animais , Modelos Animais de Doenças , Nefropatias/imunologia , Nefropatias/microbiologia , Camundongos , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Peixe-Zebra/imunologiaRESUMO
PURPOSE: To describe the appearance and maturation of dark-adapted oscillatory potentials (OPs) in electroretinograms (ERGs) recorded from preterm infants, and to determine any effect of retinopathy of prematurity (ROP). METHODS: Dark-adapted ERGs were recorded in conjunction with screening for ROP and at outpatient follow-up, using a flash luminance of 11.3 scot cd s m(-2) (4.06 phot cd s m(-2)). Eligible infants were born before 31 weeks' gestation and/or weighed ≤1,250 grams at birth. RESULTS: Presence or absence of OPs was established for 68 ERG recordings from 38 infants at maturities ranging from 30 weeks' postmenstrual age (PMA) to 28 weeks' post-term corrected age. 20 infants did not develop ROP, eight developed stage 1, one stage 2 and one stage 3 disease which regressed spontaneously. Eight infants received treatment for threshold ROP. OPs were present in 50 % of infants at 36 weeks' PMA and in all by 50 weeks' PMA. The earliest appearance of OPs was at 30+5 weeks' PMA. Individual OP amplitudes increased and peak time of individual OPs decreased with increasing maturity. For infants with threshold ROP summed OP amplitudes tended to be smaller prior to treatment (6.5 vs 9.9µV, P = 0.09) and were significantly smaller by 50 weeks' PMA (14 vs 30µV, P = 0.007). OP1 was less likely to be present in infants who developed stage 3 or worse ROP (P = 0.000). CONCLUSIONS: Dark-adapted OPs are recordable in some preterm infants from 30 weeks' PMA. Relative suppression of early OPs is a potential marker for developing ROP.
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Adaptação à Escuridão/fisiologia , Eletrorretinografia , Recém-Nascido Prematuro , Retina/fisiopatologia , Retinopatia da Prematuridade/fisiopatologia , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido de muito Baixo Peso , Fotocoagulação a Laser , Oscilometria , Estimulação Luminosa , Retinopatia da Prematuridade/cirurgiaRESUMO
PURPOSE: Although premature birth is recognised as a cause of cerebral visual impairment (CVI), which can include cerebral visual dysfunction (CVD), the incidence and nature of CVD in prematurely born children is not known. METHODS: A prospective, controlled investigation was undertaken of forty-six, mainstream primary school children, prematurely born with gestations of 24.0-34.6 weeks, and of 130 control (term-born) children. Assessments were made of IQ, ophthalmic functions, visual perception and visual attention. Structured history-taking seeking evidence of behavioural features of CVI used a question inventory. Obstetric, neonatal and paediatric medical histories were documented from case records. RESULTS: Fifteen out of forty-six (33 %) of the prematurely born children-"cluster A"-revealed behaviours corresponding with CVD on cluster analysis of the CVI inventory. The whole prematurely born group performed worse than controls on all visual perception tests and all four visual attention tests. Children in cluster A were responsible for this effect, performing worse than controls on all visual perception and visual attention tests except visual closure, while cluster B prematurely born children performed no differently to controls. CONCLUSIONS: The prevalence of CVD in these prematurely born children is between 21-47 % (95 % CI), with a pattern similar to "dorsal stream dysfunction". Currently available perceptual tests appear to be unable to identify the specific pattern of problems noted in this group. Many studies have provided evidence of cognitive and intellectual dysfunction in prematurely born children, and it is possible that CVD is a contributor. The CVI inventory is a potential means of identifying and characterising the condition, which can be ameliorated with simple strategies.
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Cegueira Cortical/fisiopatologia , Recém-Nascido Prematuro , Transtornos da Percepção/fisiopatologia , Percepção Visual/fisiologia , Cegueira Cortical/diagnóstico , Criança , Pré-Escolar , Sensibilidades de Contraste/fisiologia , Percepção de Profundidade/fisiologia , Feminino , Idade Gestacional , Humanos , Masculino , Anamnese , Transtornos da Percepção/diagnóstico , Nascimento Prematuro , Prevalência , Estudos Prospectivos , Instituições Acadêmicas , Perfil de Impacto da DoençaRESUMO
BACKGROUND/AIM: Early and accurate diagnosis of functional visual loss (FVL) allows optimum management. Visual evoked potentials (VEPs) offer a means of objectively estimating acuity and therefore could assist with early and accurate diagnosis. The aim of this study was to assess the sensitivity and specificity of the step VEP in diagnosing FVL. METHODS: A retrospective audit was conducted in 36 school-aged children presenting with reduced visual acuity and clinical suspicion of FVL. All had undergone step VEP testing as part of their investigation. Medical notes were reviewed, and where necessary, referring centres, general practitioners or electronic clinical portals were consulted to obtain longer-term outcome data. RESULTS: Twenty-seven of the 36 patients (75%) were classified as having had FVL: all had a normal step VEP spatial threshold. Nine patients (25 %) had an organic cause for their acuity loss, of whom seven had abnormal step VEP spatial thresholds: the other two patients had some functional overlay to their organic disease. The step VEP sensitivity was 78% (95% confidence interval 40-96%), and specificity was 100% (95% confidence interval 84-100%). CONCLUSION: The high specificity of the step VEP for FVL warrants increased suspicion of an organic cause should the step VEP spatial threshold be abnormal.
Assuntos
Potenciais Evocados Visuais/fisiologia , Transtornos da Visão/diagnóstico , Acuidade Visual , Criança , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Transtornos da Visão/fisiopatologiaRESUMO
Background/Objectives: Remote assessment of children's visual acuity became necessary during the COVID-19 pandemic. This study aimed to assess the extent of agreement between hospital-based clinical testing and clinician-led home-based testing. Subjects/Methods: 50 children aged 2-16 (median 8) years attending hospital eye services at two UK hospitals had routine hospital-based acuities compared with subsequent online, orthoptist-supervised home visual acuities. Agreement was assessed using intra-class correlation and Bland-Altman plots, as was test-retest (TRT) agreement of two, repeated home acuity tests. Results: Monocular acuities tested at hospital and at home were obtained from all 50 children; 33 also had binocular acuities in both settings and 35 had acuities retested immediately at home. Most children were tested at home using a computer or tablet; two were tested with a smartphone. No mean test differences were found for hospital vs home testing (-0.004 (95% CI -0.06-0.05) and -0.008 (95% CI -0.04-0.03) for binocular and monocular testing, respectively). Limits of agreement (LOAs) were ±0.32 and ±0.35 logMAR for binocular and monocular testing, respectively. LOAs for inter-ocular acuity differences (hospital vs home) were -0.15-0.25 logMAR. TRT monocular acuity agreement was excellent, with an LOA of ±0.14 logMAR. Conclusions: We found good (binocular) and excellent (monocular) agreement between hospital and home acuity testing. LOAs were in keeping with multiple changes between measures (test; setting; time; tester) and a cohort including patients as young as two years old. Even smartphone testing proved feasible. Inability of the supervising orthoptist to check test distance or device calibration/orientation was a limitation, likely contributing to the breadth of LOAs. Home vision testing is feasible and accurate, but its precision, acceptability, health economic impact and carbon impact require more attention.
RESUMO
Aim: The aim of this study was to examine executive function and emotional and behavioural difficulties of children aged between 8 and 10 years who had been prenatally exposed to methadone, compared to non-exposed peers. Methods: Prospective study: third follow-up of an original cohort of 153 children born to methadone-maintained opioid-dependent mothers 2008-2010: previous investigations were at 1-3 days and at 6-7 months of age. Carers completed the Strength and Difficulties Questionnaire (SDQ) and the Behaviour Rating Inventory of Executive Function, Second Edition (BRIEF®2). Results were compared between exposed and non-exposed groups. Results: Carers of 33 of 144 traceable children completed the measures. SDQ responses showed no group differences on subscales of emotional symptoms, conduct problems, or peer relationship problems. A marginally higher proportion of exposed children had a high or very high hyperactivity subscale score. Exposed children scored significantly higher on BRIEF®2 behavioural, emotional, and cognitive regulation indices, and on the global executive composite. After controlling for potentially confounding higher reported maternal tobacco use in the exposed group via regression modelling, the effect of methadone exposure reduced. Interpretation: This study supports evidence that methadone exposure in utero is associated with adverse neurodevelopmental outcomes in childhood. Challenges in studying this population include difficulties with long-term follow-up and controlling for potentially confounding factors. Further investigation of the safety of methadone and other opioids in pregnancy must include consideration of maternal tobacco use.