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2.
Vision Res ; 222: 108439, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38896923

RESUMO

It is important to understand the development of meridional anisotropies in neurotypical children since those with poor visual development, such as amblyopia, can have different patterns of meridional anisotropies. While the oblique effect is usually observed in adults, neurotypical children who have normal 20/20 visual acuity tend to demonstrate a horizontal effect electrophysiologically. In this longitudinal study, orientation-specific visual evoked potentials (osVEPs) and psychophysical grating acuity were used to investigate the changes in the meridional anisotropies in children aged 3.8 to 9.2 years over two visits averaging four months apart. While it was hypothesized that the electrophysiological horizontal effect may shift towards an oblique effect, it was found that the electrophysiological horizontal effect persisted to be present in response to the suprathreshold moderate contrast 4 cycles-per-degree grating stimuli. Psychophysical grating acuity, however, demonstrated an oblique effect when assessed binocularly. In addition, a significant effect of visit, representing an increase in the average age over this period, was observed in the average osVEP C3 amplitudes (4.5 µV) and psychophysical grating acuity (0.28 octaves or approximately 1-line on the logMAR chart). These findings are relevant when evaluating amblyopia treatments and interventions, as it confirms the necessity to take into account of the effect of normal maturation and learning effects when evaluating young children. Special attention should also be given to children with early-onset myopia and high astigmatism even when their visual acuity is 20/20 as the electrophysiological findings are suggestive of poor visual development, which warrants further investigation.

3.
Clin Exp Optom ; : 1-7, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844079

RESUMO

CLINICAL RELEVANCE: Colour overlays and lenses are used to relieve symptoms in some patients diagnosed with visual stress, but evidence to support this practice is lacking. In this small randomised crossover trial, a range of colours are beneficial and precise colour specification does not enhance this effect. BACKGROUND: This randomised, double-masked crossover trial aimed to test effectiveness of precisely selected lens tints for visual stress. METHODS: Twenty-nine participants aged 11 to 72 (mean 30) years diagnosed with visual stress were issued with their selected coloured overlay then with tinted lenses at two colour settings. An eye examination and coloured overlay test were followed by intuitive colorimetry to select a colour to minimise symptoms (optimal tint) and the closest setting at which the symptoms returned (sub-optimal, or placebo tint). The tints were worn for one month each in randomised order. Reading speed was measured using the Wilkins Rate of Reading Test, a subjective scale was used to gauge symptoms, and the patient was asked to indicate whether one of the tints alleviated their symptoms more than the other. RESULTS: Reading speed was significantly higher with colour than without (p < 0.001), but was similar with the overlay and both tints (p = 1.0). Discomfort/distortion rating (1-7) was lower with colour than without (p < 0.001), but no difference was found between the overlay and both tints (p > 0.1). About half (47%) of the patients preferred/strongly preferred their optimal tint, and 39% preferred/strongly preferred their sub-optimal tint, while 14% had no preference. CONCLUSIONS: While our patients read more quickly and were more comfortable when using a tint, there was no difference in outcome between the optimal and sub-optimal tints. These results suggest that for patients diagnosed with visual stress, precision tints are no more helpful than sub-optimal, placebo tints.

4.
Optom Vis Sci ; 100(4): 239-247, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36856557

RESUMO

SIGNIFICANCE: Partial improvement in stereoacuity may be achieved by balancing the contrast input to the two eyes of patients with bilaterally asymmetric keratoconus. PURPOSE: Interocular differences in image quality, characterized by dissimilar contrast loss and phase shifts, are implicated in stereoacuity loss in keratoconus. This study determined whether contrast balancing improves stereoacuity in this disease condition and, if so, whether it is dependent on the baseline interocular contrast imbalance. METHODS: Interocular contrast imbalance and stereoacuity of 43 subjects (16 to 33 years) with bilaterally asymmetric keratoconus were tested with spectacle correction as baseline using a binocular rivalry paradigm and random-dot stereograms, respectively. Stereoacuity measurements were repeated in a subset of 33 subjects at their contrast balance point (i.e., contrast level in stronger eye allowing balanced rivalry with 100% contrast in weaker eye) and with contrast levels biased in favor of stronger or weaker eye, all conditions in randomized order. RESULTS: Contrast imbalance level was significantly correlated with the subject's stereoacuity at baseline ( r = -0.47, P = .002). The median (25th to 75th interquartile range) stereoacuity improved by 34.6% (19.0 to 65.1%) from baseline (748.8 arc sec [261.3 to 1257.3 arc sec]) to the contrast balanced condition (419.0 arc sec [86.6 to 868.9 arc sec]) ( P < .001), independent of their baseline stereoacuity or contrast imbalance levels ( r < 0.2, P > .26 for both). Contrast bias in favor of the weaker eye (881.3 arc sec [239.6 to 1707.6 arc sec]) worsened stereoacuity more than a bias toward the stronger eye (502.6 arc sec [181.9 to 1161.4 arc sec]), both relative to the contrast balanced condition ( P < .002). CONCLUSIONS: Interocular contrast balancing partially improves stereoacuity in bilaterally asymmetric keratoconus, independent of their baseline contrast imbalance level. Cyclopean viewing may be inherently biased toward the input from the stronger eye in keratoconus.


Assuntos
Percepção de Profundidade , Ceratocone , Humanos , Ceratocone/diagnóstico , Ceratocone/terapia , Visão Binocular , Acuidade Visual , Olho
5.
Ophthalmic Physiol Opt ; 43(4): 710-724, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36881493

RESUMO

PURPOSE: Research suggests that there are challenges in the accessibility of eye care for children in England. This study explores the barriers and enablers to eye examinations for children under 5 years of age from the perspective of community optometrists in England. METHODS: Optometrists working in community settings were invited to participate in virtual focus group discussions using an online platform based on a topic guide. The discussions were audio-recorded, transcribed and thematically analysed. Themes were derived from the focus group data based on the study aim and research question. RESULTS: Thirty optometrists participated in the focus group discussions. The overarching themes identified as barriers to eye examinations for young children in a community setting were as follows: 'Time and Money', 'Knowledge, Skills and Confidence', 'Awareness and Communication', 'Range of Attitudes' and 'Clinical Setting'. The key themes for enabling eye examinations for young children were as follows: 'Improving behaviour', 'Enhancing training and education', 'Enhancing eye care services', 'Raising awareness', 'Changes in professional bodies' and 'Balancing commercial pressures and health care'. CONCLUSION: Time, money, training and equipment are perceived by optometrists as key factors in providing an eye examination for a young child. This study identified a need for improved training and robust governance related to eye examinations for young children. There is a need for change within eye care service delivery such that all children, regardless of age and ability, are examined regularly, and by conducting these examinations, optometrists remain confident.


Assuntos
Optometristas , Optometria , Humanos , Criança , Pré-Escolar , Atenção à Saúde , Pesquisa Qualitativa , Inglaterra , Grupos Focais
6.
Ophthalmic Physiol Opt ; 43(1): 6-16, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36101930

RESUMO

PURPOSE: Correction of refractive error in children is important for visual and educational development. The aim of this questionnaire-based study was to explore paediatric refractive correction by optometrists in England. METHODS: An online questionnaire was piloted and distributed to optometrists in England. The questionnaire asked about respondents' characteristics (such as type of practice), management of refractive error in 1- and 3-year-old children and sources of information used as a basis for decisions on prescribing refractive error in children. RESULTS: Two hundred and ninety-three questionnaires were returned, although only 139 (47%) were fully completed. In an average month, about half of respondents examined no children between 0 and 2 years of age, and about half examined no more than five children aged 3-4 years. A significant proportion indicated they would refer children aged 1 or 3 years with refractive error and no other signs or symptoms into the hospital eye service. Almost a quarter would prescribe in full or in part an isometropic refractive correction of +2.00 D for a 3-year-old (within the normal range) with no other signs or symptoms, suggesting a degree of unnecessary prescribing. Almost all would act in cases of clinically significant refractive error. Respondents made similar use of their colleagues, optometric or postgraduate/continuing education, professional guidance and peer-reviewed research as sources of evidence on which to base decisions about prescribing for paediatric refractive errors. Most reported 'never' or 'rarely' using Cochrane reviews. CONCLUSIONS: These results suggest optometrists often defer management of paediatric refractive error to the hospital eye service, with implications in terms of underutilisation of community optometric expertise and burden on the National Health Service. In some cases, the results indicate a mismatch between respondents' reported management and existing guidance/guidelines on paediatric prescribing.


Assuntos
Medicina Estatal , Humanos , Criança , Pré-Escolar , Inglaterra
7.
Br J Ophthalmol ; 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36562766

RESUMO

AIM: Much existing data on childhood refractive error prevalence in India were gathered in local studies, many now dated. The aim of this study was to estimate the prevalence, severity and determinants of refractive errors among school-going children participating in a multistate vision screening programme across India. METHODS: In this cross-sectional study, vision screening was conducted in children aged 5-18 years at schools in five states using a pocket vision screener. Refractive error was measured using retinoscopy, and subjective refraction and was defined both by spherical equivalent (SE) and spherical ametropia, as myopia ≤-0.5 diopters (D), hyperopia ≥+1.0 D and/or astigmatism as >0.5 D. Data from the eye with less refractive error were used to determine prevalence. RESULTS: Among 2 240 804 children (50.9% boys, mean age 11.5 years, SD ±3.3), the prevalence of SE myopia was 1.57% (95% CI 1.54% to 1.60%) at 5-9 years, 3.13% (95% CI 3.09% to 3.16%) at 10-14 years and 4.8% (95% CI 4.73% to 4.86%) at 15-18 years. Hyperopia prevalence was 0.59% (95% CI 0.57% to 0.61%), 0.54% (95% CI 0.53% to 0.56%) and 0.39% (95% CI 0.37% to 0.41%), respectively. When defined by spherical ametropia, these values for myopia were 0.84%, 2.50% and 4.24%, and those for hyperopia were 2.11%, 2.41% and 2.07%, respectively.Myopia was associated with older age, female gender, private school attendance, urban location and state. The latter appeared to be driven by higher literacy rates. CONCLUSIONS: Refractive error, especially myopia, is common in India. Differences in prevalence between states appear to be driven by literacy rates, suggesting that the burden of myopia may rise as literacy increases.

8.
Ophthalmic Physiol Opt ; 42(6): 1276-1288, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35913773

RESUMO

OBJECTIVE: To determine the diagnostic agreement of non-cycloplegic and cycloplegic refraction in children. METHOD: The study methodology followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Electronic databases were searched for comparative studies exploring refraction performed on children under non-cycloplegic and cycloplegic conditions. There was no restriction on the year of publication; however, only publications in the English language were eligible. Inclusion criteria consisted of children aged ≤12 years, any degree or type of refractive error, either sex and no ocular or binocular co-morbidities. The QUADAS-2 tool was used to evaluate the risk of bias. Meta-analysis was conducted to synthesise data from all included studies. Subgroup and sensitivity analyses were undertaken for those studies with a risk of bias. RESULTS: Ten studies consisting of 2724 participants were eligible and included in the meta-analysis. The test for overall effect was not significant when comparing non-cycloplegic Plusoptix and cycloplegic autorefractors (Z = 0.34, p = 0.74). The pooled mean difference (MD) was -0.08 D (95% CI -0.54 D, +0.38 D) with a prediction interval of -1.72 D to +1.56 D. At less than 0.25 D, this indicates marginal overestimation of myopia and underestimation of hyperopia under non-cycloplegic conditions. When comparing non-cycloplegic autorefraction with a Retinomax and Canon autorefractor to cycloplegic refraction, a significant difference was found (Z = 9.79, p < 0.001) and (Z = 4.61, p < 0.001), respectively. DISCUSSION: Non-cycloplegic Plusoptix is the most useful autorefractor for estimating refractive error in young children with low to moderate levels of hyperopia. Results also suggest that cycloplegic refraction must remain the test of choice when measuring refractive error ≤12 years of age. There were insufficient data to explore possible reasons for heterogeneity. Further research is needed to investigate the agreement between non-cycloplegic and cycloplegic refraction in relation to the type and level of refractive error at different ages.


Assuntos
Hiperopia , Miopia , Erros de Refração , Criança , Pré-Escolar , Humanos , Hiperopia/diagnóstico , Midriáticos , Miopia/diagnóstico , Refração Ocular , Erros de Refração/diagnóstico , Testes Visuais
9.
PLoS One ; 16(12): e0261308, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34972107

RESUMO

Early presentation for childhood cataract surgery is an important first step in preventing related visual impairment and blindness. In the absence of neonatal eye screening programmes in developing countries, the early identification of childhood cataract remains a major challenge. The primary aim of this study was to identify potential barriers to accessing childhood cataract services from the perspective of parents and carers, as a critical step towards increasing the timely uptake of cataract surgery. In-depth interviews were conducted using a pre-designed topic guide developed for this study to seek the views of parents and carers in nine geographic locations across eight states in India regarding their perceived barriers and enablers to accessing childhood cataract services. A total of 35 in-depth interviews were conducted including 30 at the hospital premises and 5 in the participants' homes. All interviews were conducted in the local language and audio taped for further transcription and analysis. Data were organised using NVivo 11 and a thematic analysis was conducted utilising the Theoretical Domains Framework (TDF), an integrative framework of behavioural theories. The themes identified from interviews related to 11 out of 12 TDF domains. TDF domains associated with barriers included: 'Environmental context and resources', 'Beliefs about consequences' and 'Social influences'. Reported enablers were identified in three theoretical domains: 'Social influences', 'Beliefs about consequences' and 'Motivations and goals'. This comprehensive TDF approach enabled us to understand parents' perceived barriers and enablers to accessing childhood cataract services, which could be targeted in future interventions to improve timely uptake.


Assuntos
Comportamento , Catarata/epidemiologia , Serviços de Saúde , Pesquisa Qualitativa , Criança , Cultura , Meio Ambiente , Objetivos , Humanos , Índia/epidemiologia , Motivação , Comportamento Social
10.
Ophthalmic Physiol Opt ; 41(5): 1021-1033, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34402083

RESUMO

PURPOSE: Good vision during childhood is vital for visual, educational, and social development. Previous research highlights challenges in the accessibility of eye care for children. This study investigates the accessibility of primary eye care for young children with typical development and those with autism in England. METHODS: A telephone survey was conducted using four hypothetical scenarios (a child aged 1, 3, 5 years and a 13-year-old with autism). Four hundred community optometric practices (100 different practices for each scenario) were contacted to explore the availability of an eye examination. The caller acted as a parent, asking about the availability of an eye examination for their child and raising concerns regarding the child. Key barriers and enablers to the accessibility of primary eye care were identified through an analysis of qualitative information. RESULTS: Of the 400 practices, only three (<1%) stated that they do not perform eye examinations on children. Fifty-six practices (14%) stated that they would examine a child at any age, the remainder (n = 341, 85%) specifying a minimum age at which they would perform eye examinations on children. Lack of 'communication' from the child and 'equipment' were identified as barriers to accessing eye care for young children. Eye care for children with autism was enabled by factors related to adaptability and appointment time. CONCLUSION: Our results suggest that communication and a lack of appropriate equipment for examining children are potential barriers to accessing primary eye care. No clear barriers were identified for an older child with autism. Eye examinations are more accessible for older children in these scenarios (aged 5 with typical development and 13 years with autism) than younger children (aged 1 and 3 years old). While the UK General Ophthalmic Services (GOS) terms do not permit contract holders to exclude categories of patients from a GOS eye exam, our findings suggest this is taking place.


Assuntos
Optometria , Atenção Primária à Saúde , Adolescente , Criança , Pré-Escolar , Inglaterra , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Pais
11.
Invest Ophthalmol Vis Sci ; 62(2): 15, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33570601

RESUMO

Purpose: Keratoconus results in image quality loss in one or both eyes due to increased corneal distortion. This study quantified the depth of monocular suppression in keratoconus due to this image quality loss using a binocular contrast rivalry paradigm. Methods: Contrast rivalry was induced in 50 keratoconic cases (11-31 years) and 12 age-matched controls by dichoptically viewing orthogonal Gabor patches of 5 cycles per degree (cpd) and 1.5 cpd spatial frequency for 120 seconds with their best-corrected spectacles and rigid gas permeable (RGP) contact lenses. The dwell time on each eye's percept was determined at baseline (100% contrast bilaterally) and at varying contrast levels (80-2.5%) in the stronger eye of keratoconus or dominant eye of controls. The contrast reduction needed in the stronger eye to balance dwell times on both eyes was considered a measure of suppression depth. Results: At baseline with 5 cpd stimuli and spectacle correction, the rivalry switches were less frequent and biased toward the stronger eye of cases, all relative to controls (P < 0.001). The contrast balance point of cases (20.51% [10.7-61%]) was lower than the controls (99.80% [98.6-100%]; P < 0.001) and strongly associated with the overall and interocular difference in disease severity (r = 0.83, P < 0.001). The suppression depth reduced for 1.5 cpd (70.8% [21.7-94%]), relative to 5 cpd stimulus (P < 0.001) and with contact lenses (80.1% [49.5-91.7%]), relative to spectacles (P < 0.001). Conclusions: The eye with lesser disease severity dominates binocular viewing in keratoconus. The suppression depth of the poorer eye depends on the extent of bilateral disease severity, optical correction modality, and the target spatial frequency.


Assuntos
Córnea/diagnóstico por imagem , Aberrações de Frente de Onda da Córnea/fisiopatologia , Ceratocone/fisiopatologia , Visão Binocular/fisiologia , Acuidade Visual , Adolescente , Adulto , Criança , Lentes de Contato , Aberrações de Frente de Onda da Córnea/diagnóstico , Óculos , Feminino , Humanos , Ceratocone/diagnóstico , Ceratocone/terapia , Masculino , Índice de Gravidade de Doença , Adulto Jovem
12.
Doc Ophthalmol ; 142(2): 197-211, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32968834

RESUMO

PURPOSE: An orientation-specific visual evoked potential (osVEP) protocol was developed to probe meridional anisotropies in children with refractive amblyopia. The aim was to characterise the osVEP response in children with bilateral refractive amblyopia, evaluate the intra-session repeatability of the main osVEP components (C1, C2 and C3), coefficient of repeatability (CoR) of the response to gratings in different meridians and determine if refractive amblyopes have poorer repeatability as compared with non-amblyopic controls. METHODS: Children aged 4-7 years with newly diagnosed and untreated bilateral refractive amblyopia and non-amblyopic controls were recruited. Orientation-specific pattern-onset VEPs were recorded in response to an achromatic sinewave grating stimulus of 4 cycles per degree under monocular and binocular stimulation. The grating lines used for monocular stimulation were parallel with the subjects' most positive and negative astigmatic meridians when considered in sphero-minus cylinder form (Meridians 1 and 2, respectively). In subjects without astigmatism, meridians 1 and 2 were designated horizontal and vertical gratings, respectively. Binocular stimuli were presented with grating lines parallel to meridians 45, 90, 135 and 180°. The repeatability of latencies of the main osVEP components (C1, C2 and C3) were investigated using two successive osVEPs recordings for each stimulus meridian and the CoR for each component's latencies were assessed. RESULTS: Seven amblyopic children (Visual acuity (VA) ranging from 0.08 to 0.40 LogMAR in the less amblyopic eye and 0.26-0.52 LogMAR in the more amblyopic eye) and 7 non-amblyopic controls (VA ranging from 0.00 to 0.02 LogMAR in either eye), with a median age of 4.6 and 7.0 years, respectively, completed the study. C1 had the highest CoR for most conditions assessed. Ratio of CoRs C1:C2 was > 2 for all binocular meridians in controls and the 90 and 180 meridians in the amblyopes; C1:C3 was > 2 for the binocularly assessed 45, 90 and 135 meridians in the controls and the 90 and 180 meridians in the amblyopes; C2:C3 were all < 2 for all meridians assessed in both groups. CONCLUSIONS: The osVEP waveforms are reliable and useful for future investigations into the meridional anisotropies in children with refractive amblyopia, particularly the C3 component. Component C1 had the poorest repeatability, which consequentially affected C2 amplitude estimation. Only C3 amplitude and latency could be consistently estimated as C2 and C3 latencies were similarly repeatable. Coefficients of repeatability of osVEP latencies did not appear to systematically differ between non-amblyopic and amblyopic children.


Assuntos
Ambliopia , Potenciais Evocados Visuais , Criança , Pré-Escolar , Eletrorretinografia , Humanos , Fatores de Tempo , Acuidade Visual
13.
Invest Ophthalmol Vis Sci ; 61(5): 5, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-32392311

RESUMO

Purpose: We investigated and characterized the patterns of meridional anisotropies in newly diagnosed refractive amblyopes using pattern onset-offset visual evoked potentials (POVEPs) and psychophysical grating acuity (GA). Methods: Twenty-five refractive amblyopes were recruited and compared with non-amblyopic controls from our previous study. Monocular POVEPs were recorded in response to sinewave 4 cycles per degree (cpd) grating stimuli oriented along each individual participants' principal astigmatic meridians, which were approximately horizontal (meridian 1) and vertical (meridian 2). Binocular POVEPs in response to the same stimuli, but oriented at 45°, 90°, 135°, and 180°, were recorded. Psychophysical GAs were assessed along the same meridians using a two-alternative non-forced-choice technique. The C3 amplitudes and peak latencies of the POVEPs and GAs were compared across meridians for both groups (refractive amblyopes and controls) using linear mixed models (monocular) and ANOVA (binocular), and post hoc analysis was conducted to determine if meridional anisotropies in this cohort of amblyopes were related to low (≤1.50 diopters [D]), moderate (1.75-2.75 D) and high (≥3.00 D) astigmatism. Results: In the newly diagnosed refractive amblyopes, there were no significant meridional anisotropies across all outcome measures, but the post hoc analysis demonstrated that C3 amplitude was significantly higher in those with low (P = 0.02) and moderate (P = 0.004) astigmatism compared to those with high astigmatism. Refractive amblyopes had poorer GA and C3 amplitudes compared to controls by approximately two lines on the logMAR chart (monocular: P = 0.013; binocular: P = 0.014) and approximately 6 µV (monocular: P = 0.009; binocular: P = 0.027), respectively. Conclusions: Deleterious effects of high astigmatism was evident in newly diagnosed refractive amblyopes, but the neural deficits do not seem to be orientation-specific for the stimulus parameters investigated.


Assuntos
Ambliopia/fisiopatologia , Potenciais Evocados Visuais/fisiologia , Orientação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Anisotropia , Astigmatismo/fisiopatologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Humanos , Psicofísica
14.
Invest Ophthalmol Vis Sci ; 60(6): 1906-1913, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31042798

RESUMO

Purpose: We investigated the pattern of meridional anisotropies, if any, for pattern onset-offset visual evoked potential (POVEPs) responses and psychophysical grating acuity (GA) in children with normal letter visual acuity (20/20 or better). Methods: A total of 29 children (aged 3-9 years), nine of whom were astigmatic (AS), were recruited. Orientation-specific monocular POVEPs were recorded in response to sinewave grating stimuli oriented along the subjects' principal AS meridians. Horizontal and vertical gratings were designated Meridians 1 and 2, respectively, for nonastigmatic patients (Non-AS). Binocular POVEPs in response to the same stimuli, but oriented at 45°, 90°, 135°, and 180°, were recorded. Psychophysical GAs were assessed monocularly and binocularly along the same meridians using the same stimuli by a 2-alternative-forced-choice staircase technique. The C3 amplitudes and peak latencies of the POVEP and GAs were compared across meridians using linear mixed models (monocular) and ANOVA (binocular). Results: There were significant meridional anisotropies in monocular C3 amplitudes regardless of astigmatism status (P = 0.001): Meridian 2 (mean ± SE Non-AS, 30.13 ± 2.07 µV; AS, 26.53 ± 2.98 µV) was significantly higher than Meridian 1 (Non-AS, 26.14 ± 1.87 µV; AS, 21.68 ± 2.73 µV; P = 0.019), but no meridional anisotropies were found for GA or C3 latency. Binocular C3 amplitude in response to horizontally oriented stimuli (180°, 29.71 ± 3.06 µV) was significantly lower than the oblique (45°, 36.62 ± 3 .05 µV; P = 0.03 and 135°, 35.95 ± 2.92 µV; P = 0.04) and vertical (90°, 37.82 ± 3.65 µV; P = 0.02) meridians, and binocular C3 latency was significantly shorter in response to vertical than oblique gratings (P ≤ 0.001). Conclusions: Meridional anisotropy was observed in children with normal vision. The findings suggest that horizontal gratings result in a small, but significantly lower POVEP amplitude than for vertical and oblique gratings.


Assuntos
Astigmatismo/fisiopatologia , Potenciais Evocados Visuais/fisiologia , Orientação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Psicofísica/métodos , Visão Binocular/fisiologia , Acuidade Visual , Anisotropia , Astigmatismo/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Masculino
16.
Eye (Lond) ; 32(12): 1811-1818, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30061651

RESUMO

PURPOSE: Cataract is one of the major causes of avoidable visual disability in children and the aim of this study was to investigate the age at which children with cataract present for surgery at tertiary hospitals across India. METHODS: A prospective multicenter study collected data from 9 eye hospitals in 8 states in India. All children admitted for cataract surgery between Nov 2015 and March 2016 were considered eligible. Parents were interviewed at the hospital by trained personnel and socio demographic information, age at diagnosis and at surgery and the relevant clinical data were obtained from the medical records. Mean age, age range at surgery were used and performed logistic regression analyses. RESULTS: Parents of 751 consecutive cases were interviewed, of which 469(63%) were boys and 548 (73%) were from rural areas. Cataract was bilateral in 493 (66%) and unilateral in 258 (34%); of the unilateral cases, 179 (69%) were due to trauma. The mean age at surgery for 'congenital' and 'developmental' cataract was 48.2 ± 50.9 and 99.7 ± 46.42 months, respectively and the mean age was lower in the southern region compared to other regions. Children with 2 or more siblings at home were five times more likely to undergo surgery within 12 months (OR, 4.69; 95% CI: 2.04-10.79; p = < 0.001). CONCLUSIONS: Late surgery for childhood cataract remains a major challenge and the factors determining this issue in India are pertinent also to several other countries and need to be addressed for every child with cataract to achieve full visual potential.


Assuntos
Extração de Catarata/estatística & dados numéricos , Implante de Lente Intraocular , Tempo para o Tratamento/estatística & dados numéricos , Adolescente , Análise de Variância , Catarata/congênito , Catarata/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Cristalino , Modelos Logísticos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Fatores Socioeconômicos , Acuidade Visual
18.
Ophthalmic Physiol Opt ; 38(4): 469, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29924403

Assuntos
Cristalino , Lentes
19.
Clin Exp Optom ; 101(4): 514-520, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29633383

RESUMO

Coloured overlays or lenses are widely available for use by children and adults with difficulties or discomfort while reading. In recent years, systematic reviews have been conducted in an attempt to establish the strength of the evidence base for this intervention. The aim of this overview is to systematically review these reviews. The methodology was published prospectively as a protocol (Prospero CRD42017059172). Online databases Medline, Cinahl, Embase and the Cochrane Library were searched for systematic reviews on the efficacy of coloured overlays or lenses for the alleviation of reading difficulty or discomfort. Included studies were appraised using the AMSTAR 2 checklist. Characteristics of included studies such as aspects of methods, results and conclusions were recorded. Both processes were conducted independently by two reviewers and any discrepancies were resolved by discussion. Thirty-one studies were found via databases and other sources. After excluding duplicates and those not fitting the inclusion criteria, four reviews were included in the analysis. While all reviews were systematic, their methodology, results and conclusions differed. Three of the four concluded that there is insufficient good quality evidence to support the use of coloured overlays or lenses for reading difficulty, while one concluded that, despite research limitations, the evidence does support their use. On balance, systematic reviews to date indicate that there is not yet a reliable evidence base on which to recommend coloured overlays or lenses for the alleviation of reading difficulty or discomfort. High quality, low bias research is needed to investigate their effectiveness in different forms of reading difficulty and discomfort for adults and children.


Assuntos
Dislexia/terapia , Óculos , Auxiliares Sensoriais , Revisões Sistemáticas como Assunto , Adulto , Criança , Humanos
20.
Fam Community Health ; 41(2): 95-104, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29461357

RESUMO

This health promotion project is a 12-week program for adults in a rural West Virginia community with a body mass index (BMI) of 25 or greater. The goals of this project were to facilitate learning through modules focusing on activity and nutrition, increase knowledge of healthy activity and nutrition, and improve weight and BMI. Each 12-week session provided evidenced-based information regarding obesity, physical activity, and nutrition. Participants completed pre- and postprogram and 1-month follow-up survey/questionnaire. Results were compared for changes in activity, nutrition, and BMI. The program resulted in positive changes: increase in activity and nutritional consumption and a decrease in BMI.


Assuntos
Promoção da Saúde/métodos , Obesidade/terapia , População Rural/tendências , Feminino , Humanos , Masculino , Inquéritos e Questionários , West Virginia
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